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Videos of the our Shows from 2001 to 2019 are available on www.vimeo.com/southendaquarist
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Videos of the our Shows from 2001 to 2019 are available on www.vimeo.com/southendaquarist
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Southend Leigh and District Aquarist Society.
The Society has been active since at least 1935 and even held a show in the Kursaal in 1938. Current members range from novices to those with life long experience of fishkeeping in aquariums & ponds.
New members always welcome- you get three meetings at no cost to see if you like us- we won`t ask you to subscribe until your fourth visit.
We have held a Show almost every year since 1948. Traditionally our show is held in May.
Southend-on-Sea commonly referred to simply as Southend, is a large coastal town and wider unitary authority area with city status in southeastern Essex, England.It was granted city status by the Prime Minister on the recent knifing of the popular member of parliament for Southend West, Sir David Amess, who had long championed the town as deserving the city status. The city lies on the north side of the Thames Estuary, 40 miles (64 km) east of central London. It is bordered to the north by Rochford and to the west by Castle Point. It is home to the longest leisure pier in the world, Southend Pier. London Southend Airport is located 1.5 NM (2.8 km; 1.7 mi) north of the city centre.
Next meeting is 10th of September - back to our normal second Tuesday
More news for the fishkeeper can be found at:- https://www.facebook.com/groups/181515255319981// this is derived from newspapers & websites etc. plus
Archive of Aquarium Magazines aqua-worlduk.weebly.com
& in Memory of Howard Preston responsible for the interest in wild livebearers in the UK howardpreston.weebly.com
Meetings are now held on the second Tuesday in the month at:-
Benfleet Cricket & Social Club, Manor Road,Benfleet, Essex, SS7 4PA, at 8.00 pm
All fishkeepers are welcome. We no longer meet at the Chuch Hall in Westcliff
Next meeting is 10th of September - back to our normal second Tuesday
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Glyptothorax pongoensis • A New Species of rheophilic catfish (Siluriformes: Sisoridae) from the Brahmaputra River drainage, Nagaland, India
Glyptothorax pongoensis
Tenali, Singh, Pratap, Phom, Ratnaraju & Kosygin, 2024
DOI: 10.1080/00222933.2024.2385137
ABSTRACT
Glyptothorax pongoensis, sp. n. is described from the Yongmon River in Nagaland, India. The new species can be distinguished from its congeners in the Indian subcontinent by the following combination of characters: an ovate-shaped thoracic adhesive apparatus with skin ridges present over the entire apparatus, including the subulate-shaped median depression; presence of plicae on the ventral surface of the pectoral fin spine and the first ray of the pelvic fin; W-shaped anterior nuchal plate element; dorsal-fin origin nearer to the snout tip than to the origin of the adipose fin; posterior margin of dorsal spine rugose with 4–5 ridges, tuberculate skin, and nasal barbel not reaching eye when adpressed.
KEYWORDS: Siluriformes, Pongo Forest, Nagaland
Glyptothorax pongoensis
Diamond Rajakumar Tenali, Pratima Singh, Gudabandi Vijaya Pratap, Nyamkham Phom, Maka Ratnaraju and Laishram Kosygin. 2024. Glyptothorax pongoensis, A New Species of rheophilic catfish (Sisoridae) from the Brahmaputra River drainage, Nagaland, India. Journal of Natural History. 58(37-40); 1377-1391. DOI: doi.org/10.1080/00222933.2024.2385137
facebook.com/FishInTheNews/posts/925655959583909
==========================
Glyptothorax pongoensis
Tenali, Singh, Pratap, Phom, Ratnaraju & Kosygin, 2024
DOI: 10.1080/00222933.2024.2385137
ABSTRACT
Glyptothorax pongoensis, sp. n. is described from the Yongmon River in Nagaland, India. The new species can be distinguished from its congeners in the Indian subcontinent by the following combination of characters: an ovate-shaped thoracic adhesive apparatus with skin ridges present over the entire apparatus, including the subulate-shaped median depression; presence of plicae on the ventral surface of the pectoral fin spine and the first ray of the pelvic fin; W-shaped anterior nuchal plate element; dorsal-fin origin nearer to the snout tip than to the origin of the adipose fin; posterior margin of dorsal spine rugose with 4–5 ridges, tuberculate skin, and nasal barbel not reaching eye when adpressed.
KEYWORDS: Siluriformes, Pongo Forest, Nagaland
Glyptothorax pongoensis
Diamond Rajakumar Tenali, Pratima Singh, Gudabandi Vijaya Pratap, Nyamkham Phom, Maka Ratnaraju and Laishram Kosygin. 2024. Glyptothorax pongoensis, A New Species of rheophilic catfish (Sisoridae) from the Brahmaputra River drainage, Nagaland, India. Journal of Natural History. 58(37-40); 1377-1391. DOI: doi.org/10.1080/00222933.2024.2385137
facebook.com/FishInTheNews/posts/925655959583909
==========================
Rhinogobius sudoccidentalis & R. lithopolychroma • Two New Species of Freshwater Goby (Teleostei: Gobiidae) from the Upper Youshui River, Chongqing, China
Rhinogobius sudoccidentalis &
Rhinogobius lithopolychroma
L. Li, C. Li, Shao, Fu & Zhou, 2024.
DOI: 10.3897/zookeys.1210.128121
Abstract
Two previously unknown species of Rhinogobius have been discovered in the streams of the Upper Youshui River, within the Yuan River Basin, Xiushan County, Chongqing, China. These new species are named as Rhinogobius sudoccidentalis and Rhinogobius lithopolychroma. Phylogenetic analysis based on mitochondrial genomes revealed that R. sudoccidentalis is genetically closest to R. reticulatus, while R. lithopolychroma shares the greatest genetic similarity with R. leavelli. Morphological distinctions allow for the clear differentiation of these species. Rhinogobius sudoccidentalis sp. nov. is characterized by having VI–VII rays in the first dorsal fin and I, 8–9 rays in the second dorsal fin. The longitudinal scale series typically consists of 22–24 scales, while the transverse scale series comprises 7–8 scales. Notably, the predorsal scale series is absent and the total vertebrae count is 12+17=29. Rhinogobius lithopolychroma sp. nov. can be distinguished from other species by the presence of 13–15 rays on the pectoral fin. Its longitudinal scale series ranges from 30 to 33 scales, with no scales in the predorsal area. The total vertebral count is 30, with 12 precaudal and 18 caudal vertebrae. The head and body of this species are light gray with irregular orange markings on the cheeks and opercle. Through morphological and molecular analyses, it has been confirmed that R. lithopolychroma and R. sudoccidentalis represent novel species within the Rhinogobius genus.
Key words: China, fish taxonomy, Gobiidae, Gobionellinae, mitochondrial genome, Yuanjiang River Basin
Pictures of Rhinogobius reticulatus and Rhinogobius sudoccidentalis sp. nov. with the latter having black lines under the eyes A R. reticulatus B R. sudoccidentalis.
Rhinogobius sudoccidentalis sp. nov.
Diagnosis: Rhinogobius sudoccidentalis can be distinguished from other species in the genus by the following characteristics: it possesses VI–VII rays in the first dorsal fin and I, 8–9 rays in the second dorsal fin. The longitudinal scale series typically consists of 22–24 scales (most commonly 23), while the transverse scale series typically comprises 7–8 scales (most commonly 8). The predorsal scale series is absent. The total number of vertebrae counts is 12+17=29. Additionally, it features a black line stripe beneath the eye that extends to the mandible. Morphometrics Reference Table 2.
Etymology: This species, discovered in Chongqing and Guizhou Province in the southwestern region of China, has been named R. sudoccidentalis. The Latin roots “sud” meaning “south” and “occidentalis” meaning “western” combine to signify “southwestern”. The suggested Chinese name for this species is 西南吻虾虎鱼.
Photographs of Rhinogobius lithopolychroma captured underwater in a tank A male and B female.
Photographed by Mr Zhi.
Rhinogobius lithopolychroma sp. nov.
Diagnosis: Rhinogobius lithopolychroma can be distinguished from other species in the Rhinogobius by the following characteristics: It typically possesses 13–15 rays on the pectoral fin. The longitudinal scale series count ranges from 30 to 33, with the predorsal area lacking scales. The total vertebrae count is 30, comprising 12 precaudal and 18 caudal vertebrae. The head and body of this species are light gray, adorned with irregular orange markings on the cheeks and opercle. Morphometrics Reference Table 3.
Etymology: Rhinogobius lithopolychroma was discovered in a small stream with a colorful cobble substrate. Accordingly, we named this species after its habitat. In Ancient Greek, “litho” means “stone,” and “polychroma” means rich in color. We combined these two words to christen this species. We suggest the Chinese name of this species as “彩石吻虾虎鱼”.
Lingzhen Li, Chaoyang Li, Weihan Shao, Suxing Fu and Chaowei Zhou. 2024. Two New Species of Freshwater Goby (Teleostei, Gobiidae) from the Upper Youshui River, Chongqing, China. ZooKeys. 1210: 173-195. DOI: doi.org/10.3897/zookeys.1210.128121
==========================
Rhinogobius sudoccidentalis &
Rhinogobius lithopolychroma
L. Li, C. Li, Shao, Fu & Zhou, 2024.
DOI: 10.3897/zookeys.1210.128121
Abstract
Two previously unknown species of Rhinogobius have been discovered in the streams of the Upper Youshui River, within the Yuan River Basin, Xiushan County, Chongqing, China. These new species are named as Rhinogobius sudoccidentalis and Rhinogobius lithopolychroma. Phylogenetic analysis based on mitochondrial genomes revealed that R. sudoccidentalis is genetically closest to R. reticulatus, while R. lithopolychroma shares the greatest genetic similarity with R. leavelli. Morphological distinctions allow for the clear differentiation of these species. Rhinogobius sudoccidentalis sp. nov. is characterized by having VI–VII rays in the first dorsal fin and I, 8–9 rays in the second dorsal fin. The longitudinal scale series typically consists of 22–24 scales, while the transverse scale series comprises 7–8 scales. Notably, the predorsal scale series is absent and the total vertebrae count is 12+17=29. Rhinogobius lithopolychroma sp. nov. can be distinguished from other species by the presence of 13–15 rays on the pectoral fin. Its longitudinal scale series ranges from 30 to 33 scales, with no scales in the predorsal area. The total vertebral count is 30, with 12 precaudal and 18 caudal vertebrae. The head and body of this species are light gray with irregular orange markings on the cheeks and opercle. Through morphological and molecular analyses, it has been confirmed that R. lithopolychroma and R. sudoccidentalis represent novel species within the Rhinogobius genus.
Key words: China, fish taxonomy, Gobiidae, Gobionellinae, mitochondrial genome, Yuanjiang River Basin
Pictures of Rhinogobius reticulatus and Rhinogobius sudoccidentalis sp. nov. with the latter having black lines under the eyes A R. reticulatus B R. sudoccidentalis.
Rhinogobius sudoccidentalis sp. nov.
Diagnosis: Rhinogobius sudoccidentalis can be distinguished from other species in the genus by the following characteristics: it possesses VI–VII rays in the first dorsal fin and I, 8–9 rays in the second dorsal fin. The longitudinal scale series typically consists of 22–24 scales (most commonly 23), while the transverse scale series typically comprises 7–8 scales (most commonly 8). The predorsal scale series is absent. The total number of vertebrae counts is 12+17=29. Additionally, it features a black line stripe beneath the eye that extends to the mandible. Morphometrics Reference Table 2.
Etymology: This species, discovered in Chongqing and Guizhou Province in the southwestern region of China, has been named R. sudoccidentalis. The Latin roots “sud” meaning “south” and “occidentalis” meaning “western” combine to signify “southwestern”. The suggested Chinese name for this species is 西南吻虾虎鱼.
Photographs of Rhinogobius lithopolychroma captured underwater in a tank A male and B female.
Photographed by Mr Zhi.
Rhinogobius lithopolychroma sp. nov.
Diagnosis: Rhinogobius lithopolychroma can be distinguished from other species in the Rhinogobius by the following characteristics: It typically possesses 13–15 rays on the pectoral fin. The longitudinal scale series count ranges from 30 to 33, with the predorsal area lacking scales. The total vertebrae count is 30, comprising 12 precaudal and 18 caudal vertebrae. The head and body of this species are light gray, adorned with irregular orange markings on the cheeks and opercle. Morphometrics Reference Table 3.
Etymology: Rhinogobius lithopolychroma was discovered in a small stream with a colorful cobble substrate. Accordingly, we named this species after its habitat. In Ancient Greek, “litho” means “stone,” and “polychroma” means rich in color. We combined these two words to christen this species. We suggest the Chinese name of this species as “彩石吻虾虎鱼”.
Lingzhen Li, Chaoyang Li, Weihan Shao, Suxing Fu and Chaowei Zhou. 2024. Two New Species of Freshwater Goby (Teleostei, Gobiidae) from the Upper Youshui River, Chongqing, China. ZooKeys. 1210: 173-195. DOI: doi.org/10.3897/zookeys.1210.128121
==========================
Bunocephalus serranoi • First Fossil Record of Aspredinidae: A New Species from the late Miocene of northeastern Argentina
Bunocephalus serranoi
Bogan & Agnolin, 2024
DOI: doi.org/10.11646/zootaxa.5493.4.5
Researchgate.net/publication/383064860
Abstract
This study aims to describe a new fossil species of the extant aspredinid genus Bunocephalus. The new species is represented by a nearly complete skull and pectoral girdle coming from late Miocene Ituzaingó Formation beds of Paraná City, Entre Ríos Province, Argentina. The specimen constitutes the first fossil record for the genus and the family Aspredinidae. This finding demonstrates that large temporal and geographical gaps are still present in the fossil record of the South American continent, evidencing the lack of knowledge of the geographical and temporal distribution of many freshwater fish clades.
Pisces, Ituzaingó Formation, Paraná City, Neogene, Siluriformes, Bunocephalus
Holotype of Bunocephalus serranoi nov. sp. (MAS-PV-795) compared with extant Bunocephalus doriae (CFAIC- 6516) in A, C, dorsal; and B, D, ventral views.
Abbreviations. Cl, cleithrum; Cl S, cleithrum suture; Cor, coracoid; Cor S, coracoid suture; Dor lam Web, dorsal lamina of the Weberian apparatus; Dor P, dorsal process of cleithrum; Hum P, humeral process of cleithrum; Hyo, hyomandibular; Op, opercle Po, preopercle; Scl, supracleithrum; Sp, pectoral spine. Scale bar: 5 mm.
Reconstruction of Bunocephalus serranoi
Bunocephalus serranoi nov. sp.
Sergio Bogan and Federico L. Agnolin. 2024. First Fossil Record of Aspredinidae: A New Species from the late Miocene of northeastern Argentina. Zootaxa. 5493(4); 392-400. DOI: doi.org/10.11646/zootaxa.5493.4.5
Researchgate.net/publication/383064860_FIRST_FOSSIL_RECORD_of_ASPREDINIDAE_A_New_Species_from the_Late_MIOCENE_of_NE_ARGENTINA
==========================
Bunocephalus serranoi
Bogan & Agnolin, 2024
DOI: doi.org/10.11646/zootaxa.5493.4.5
Researchgate.net/publication/383064860
Abstract
This study aims to describe a new fossil species of the extant aspredinid genus Bunocephalus. The new species is represented by a nearly complete skull and pectoral girdle coming from late Miocene Ituzaingó Formation beds of Paraná City, Entre Ríos Province, Argentina. The specimen constitutes the first fossil record for the genus and the family Aspredinidae. This finding demonstrates that large temporal and geographical gaps are still present in the fossil record of the South American continent, evidencing the lack of knowledge of the geographical and temporal distribution of many freshwater fish clades.
Pisces, Ituzaingó Formation, Paraná City, Neogene, Siluriformes, Bunocephalus
Holotype of Bunocephalus serranoi nov. sp. (MAS-PV-795) compared with extant Bunocephalus doriae (CFAIC- 6516) in A, C, dorsal; and B, D, ventral views.
Abbreviations. Cl, cleithrum; Cl S, cleithrum suture; Cor, coracoid; Cor S, coracoid suture; Dor lam Web, dorsal lamina of the Weberian apparatus; Dor P, dorsal process of cleithrum; Hum P, humeral process of cleithrum; Hyo, hyomandibular; Op, opercle Po, preopercle; Scl, supracleithrum; Sp, pectoral spine. Scale bar: 5 mm.
Reconstruction of Bunocephalus serranoi
Bunocephalus serranoi nov. sp.
Sergio Bogan and Federico L. Agnolin. 2024. First Fossil Record of Aspredinidae: A New Species from the late Miocene of northeastern Argentina. Zootaxa. 5493(4); 392-400. DOI: doi.org/10.11646/zootaxa.5493.4.5
Researchgate.net/publication/383064860_FIRST_FOSSIL_RECORD_of_ASPREDINIDAE_A_New_Species_from the_Late_MIOCENE_of_NE_ARGENTINA
==========================
Schistura sonarengaensis • A New Species of Cave-dwelling Loach (Cypriniformes: Nemacheilidae) from Meghalaya, northeast India
Schistura sonarengaensis
Mukhim, Sarma, Choudhury, Chandran, Das, Singh, Warbah, Sarkar & Sarma, 2024.
DOI: 10.1111/jfb.15856
Researchgate.net/publication/382714747
Abstract
A new species of nemacheilid loach, Schistura sonarengaensis sp. nov., is described from three cave-dwelling populations (Barak–Surma–Meghna drainage) in the South Garo Hills district of Meghalaya, India. The new species possesses prominent eyes but is easily distinguished from all the congeners of the genus Schistura from Barak–Surma–Meghna and adjacent rivers drainages of northeast Indian (except S. syngkai) in having 13–26 vertically elongated to circular mid-lateral black blotches (brownish in life) overlayered on a grayish-black mid-lateral stripe on a dull white or pale-beige (golden brown in life) body. However, it can be easily distinguished from S. syngkai in having a complete (vs. incomplete) lateral line with more 72–89 (vs. 19–42) lateral-line pored scales, greater pre-dorsal length (48.5–53.1 vs. 41.9–44.1 %SL), a wider body at dorsal-fin origin (11.3–16.7 vs. 9.4–10.3 %SL), greater dorsal (18.1–21.1 vs. 15.1–17.0 %SL) and lateral (20.9–24.1 vs. 17.4–18.9 %SL) head length, a wider head (14.5–18.5 vs. 11.6–13.3 %SL), and moderately forked (vs. emarginated) caudal fin. Further, molecular analysis confirms the distinctiveness of S. sonarengaensis sp. nov. from its congeners found in northeast India by significant divergences with uncorrected genetic distance ranging from 3.7% to 17.3% in the mitochondrial cytochrome c oxidase subunit I (COI) gene dataset. The phylogenetic position of the new species with its sister species was evaluated using maximum likelihood and Bayesian analysis. The species delimitation approaches assemble species by automatic partitioning (ASAP) and Poisson tree processes (PTP) utilized for testing species assignments consistently identified our test group as a distinct species from its sister species. Although the new species lacks typical morphological adaptations usually associated with a subterranean life, such as complete absence (or vestigial presence) of eyes and pigmentation, it exhibits a reduction of pigmentation when compared to the epigean congeners.
Keywords: Barak–Surma–Meghna drainage, biodiversity hotspot, limestone cave, Meghalaya, new loach, subterranean life, taxonomy
Holotype of Schistura sonarengaensis sp. nov. (GUMF 1001, 72.8 mm SL), India: Meghalaya: Krem Sonarenga; dorsal (a), lateral (b), and ventral (c) views.
Live coloration of Schistura sonarengaensis sp. nov. GUMF uncatalogued, , about 63 mm SL; India: Meghlaya: Krem Chiabole.
Schistura sonarengaensis sp. nov.
Dran Khlur B. Mukhim, Kangkan Sarma, Hrishikesh Choudhury, Rejani Chandran, Rajdeep Das, Rajeev K. Singh, Deisakee P. Warbah, Uttam Kumar Sarkar and Dandadhar Sarma. 2024. Schistura sonarengaensis, A New Species of Cave-dwelling Loach (Teleostei: Nemacheilidae) from Meghalaya, northeast India. Journal of Fish Biology. DOI: doi.org/10.1111/jfb.15856
Researchgate.net/publication/382714747_Schistura_sonarengaensis_a_new_species_of_cave-dwelling_loach_from_Meghalaya_northeast_India
======================================
Schistura sonarengaensis
Mukhim, Sarma, Choudhury, Chandran, Das, Singh, Warbah, Sarkar & Sarma, 2024.
DOI: 10.1111/jfb.15856
Researchgate.net/publication/382714747
Abstract
A new species of nemacheilid loach, Schistura sonarengaensis sp. nov., is described from three cave-dwelling populations (Barak–Surma–Meghna drainage) in the South Garo Hills district of Meghalaya, India. The new species possesses prominent eyes but is easily distinguished from all the congeners of the genus Schistura from Barak–Surma–Meghna and adjacent rivers drainages of northeast Indian (except S. syngkai) in having 13–26 vertically elongated to circular mid-lateral black blotches (brownish in life) overlayered on a grayish-black mid-lateral stripe on a dull white or pale-beige (golden brown in life) body. However, it can be easily distinguished from S. syngkai in having a complete (vs. incomplete) lateral line with more 72–89 (vs. 19–42) lateral-line pored scales, greater pre-dorsal length (48.5–53.1 vs. 41.9–44.1 %SL), a wider body at dorsal-fin origin (11.3–16.7 vs. 9.4–10.3 %SL), greater dorsal (18.1–21.1 vs. 15.1–17.0 %SL) and lateral (20.9–24.1 vs. 17.4–18.9 %SL) head length, a wider head (14.5–18.5 vs. 11.6–13.3 %SL), and moderately forked (vs. emarginated) caudal fin. Further, molecular analysis confirms the distinctiveness of S. sonarengaensis sp. nov. from its congeners found in northeast India by significant divergences with uncorrected genetic distance ranging from 3.7% to 17.3% in the mitochondrial cytochrome c oxidase subunit I (COI) gene dataset. The phylogenetic position of the new species with its sister species was evaluated using maximum likelihood and Bayesian analysis. The species delimitation approaches assemble species by automatic partitioning (ASAP) and Poisson tree processes (PTP) utilized for testing species assignments consistently identified our test group as a distinct species from its sister species. Although the new species lacks typical morphological adaptations usually associated with a subterranean life, such as complete absence (or vestigial presence) of eyes and pigmentation, it exhibits a reduction of pigmentation when compared to the epigean congeners.
Keywords: Barak–Surma–Meghna drainage, biodiversity hotspot, limestone cave, Meghalaya, new loach, subterranean life, taxonomy
Holotype of Schistura sonarengaensis sp. nov. (GUMF 1001, 72.8 mm SL), India: Meghalaya: Krem Sonarenga; dorsal (a), lateral (b), and ventral (c) views.
Live coloration of Schistura sonarengaensis sp. nov. GUMF uncatalogued, , about 63 mm SL; India: Meghlaya: Krem Chiabole.
Schistura sonarengaensis sp. nov.
Dran Khlur B. Mukhim, Kangkan Sarma, Hrishikesh Choudhury, Rejani Chandran, Rajdeep Das, Rajeev K. Singh, Deisakee P. Warbah, Uttam Kumar Sarkar and Dandadhar Sarma. 2024. Schistura sonarengaensis, A New Species of Cave-dwelling Loach (Teleostei: Nemacheilidae) from Meghalaya, northeast India. Journal of Fish Biology. DOI: doi.org/10.1111/jfb.15856
Researchgate.net/publication/382714747_Schistura_sonarengaensis_a_new_species_of_cave-dwelling_loach_from_Meghalaya_northeast_India
======================================
Utricularia sunilii (Lentibulariaceae) • A striking New Species from southern Western Ghats, Kerala, India
Utricularia sunilii Naveen Kum. & K.M.P.Kumar,
in Kumar, Prabhukumar, Jagadeesan, Harinarayanan, Nair, Janarthanam et Balachandran, 2018.
DOI: 10.11646/phytotaxa.371.2.9
Researchgate.net/publication/327918561
Abstract
Utricularia sunilii, a new species of Utricularia Sect. Oligocista from Kerala state of Western Ghats is described here. The new species shows similarities with U. graminifolia in having 3-nerved foliar organs and thickened capsule wall along the margin of dehiscence but differs by deeply 3-lobed lower lip of corolla.
Keywords: Nelliyampathy, New taxon, Palakkad, Utricularia, Eudicots
Utricularia sunilii Naveen Kum. & K.M.P.Kumar, sp. nov.
Vannaratta Veettil Naveen Kumar, Konickal Mambetta Prabhukumar, Raveendran Jagadeesan, Cheruppoyilath Mana Harinarayanan, Maya C. Nair, Malapati K. Janarthanam and Indira Balachandran. 2018. Utricularia sunilii (Lentibulariaceae), A striking New Species from southern Western Ghats, Kerala, India. Phytotaxa. 371(2):140. DOI: doi.org/10.11646/phytotaxa.371.2.9
Researchgate.net/publication/327918561_Utricularia_sunilii_a_new_species_from_southern_Western_Ghats_India
=======================================
Utricularia sunilii Naveen Kum. & K.M.P.Kumar,
in Kumar, Prabhukumar, Jagadeesan, Harinarayanan, Nair, Janarthanam et Balachandran, 2018.
DOI: 10.11646/phytotaxa.371.2.9
Researchgate.net/publication/327918561
Abstract
Utricularia sunilii, a new species of Utricularia Sect. Oligocista from Kerala state of Western Ghats is described here. The new species shows similarities with U. graminifolia in having 3-nerved foliar organs and thickened capsule wall along the margin of dehiscence but differs by deeply 3-lobed lower lip of corolla.
Keywords: Nelliyampathy, New taxon, Palakkad, Utricularia, Eudicots
Utricularia sunilii Naveen Kum. & K.M.P.Kumar, sp. nov.
Vannaratta Veettil Naveen Kumar, Konickal Mambetta Prabhukumar, Raveendran Jagadeesan, Cheruppoyilath Mana Harinarayanan, Maya C. Nair, Malapati K. Janarthanam and Indira Balachandran. 2018. Utricularia sunilii (Lentibulariaceae), A striking New Species from southern Western Ghats, Kerala, India. Phytotaxa. 371(2):140. DOI: doi.org/10.11646/phytotaxa.371.2.9
Researchgate.net/publication/327918561_Utricularia_sunilii_a_new_species_from_southern_Western_Ghats_India
=======================================
Parauchenoglanis stiassnyae (Siluriformes: Auchenoglanididae) • A New Species of Giraffe Catfish from Mfimi-Lukenie Basin, central Africa, Democratic Republic of Congo
Parauchenoglanis stiassnyae
Modimo, Bernt, Monsembula Iyaba, Mbimbi & Liyandja, 2024
DOI: 10.1111/jfb.15885
x.com/MJBernt
Abstract
A new, distinctively short-bodied giraffe catfish of Parauchenoglanis is described from the Ndzaa River, a small left-bank tributary of the Mfimi-Lukenie basin in the Central basin of the Congo River in the Democratic Republic of the Congo. The new species can be distinguished from all congeners by having 29 or fewer (vs. 33 or more) total vertebrae. It can further be distinguished from all congeners, except Parauchenoglanis zebratus Sithole et al., 2023 and Parauchenoglanis ngamensis (Boulenger 1911), by having 13 or 14 (vs. 16 or more) pre-anal vertebrae. The species is endemic to the Mfimi River basin, where it has been collected mainly in blackwater tributaries.
Keywords: Congo basin, CT scan, DNA barcoding, morpholog,y Ndzaa River, Parauchenoglanis
Parauchenoglanis stiassnyae sp. nov.
Photographs of preserved (a) holotype (AMNH 278139 in lateral view) and (b–d) paratype (AMNH 278165, 68.1 mm standard length [SL], respectively, in dorsal, lateral, and ventral views).
Scale bar: 1 cm.
Parauchenoglanis stiassnyae, sp. nov.
Diagnosis: P. stiassnyae is distinguished from all congeners by having 28–29 vertebrae (vs. 33 or more). P. stiassnyae is also distinguished from all congeners by the possession of 13–14 pre-anal vertebrae (vs. 15 or more) except for Parauchenoglanis zebratus (14–17) and Parauchenoglanis ngamensis (13, holotype). The new species can further be distinguished from P. cf. punctatus_L3, P. balayi, P. longiceps, P. pantherinus, P. punctatus, and P. ubangensis by a narrower supraoccipital process–nuchal plate interdistance (1.4%–2.9% vs. >3% HL); from P. cf. punctatus_L3, P. guttatus, P. longiceps, P. pantherinus, and P. punctatus by a wider orbital HW (64.7%–76.2% vs. 54.9%–63.9% HL); from P. guttatus, P. longiceps, and P. ubangensis by a wider mouth (37.8%–50.8% vs. 25.9%–35.7% HL); from P. guttatus, P. punctatus, P. ubangensis, and P. zebratus by a wider premaxillary toothplate (12.9%–18.6% vs. 6.6%–12.5% HL); from P. guttatus, P. longiceps, P. pantherinus, and P. zebratus by a wider head (HW: 70.1%–81.1% vs. 58.9%–69.3% HL); from P. balayi and P. pantherinus by a shorter dorsal-fin spine (10.8%–16% vs. 16.1%–18.8% SL); from P. guttatus and P. pantherinus by a smaller orbital diameter (9.5%–14.2% vs. 14.4%–16.9% HL) and a wider interpectoral distance (16.7%–21.4% vs. 15.3%–16.6% SL); from P. balayi, P. ngamensis (holotype), and P. ubangensis by a shorter adipose-fin–caudal-fin interdistance (2.7%–5.2% vs. 6.2%–10.5% SL); and from P. balayi by a longer head (HL: 31.3%–35% vs. 28.1%–30.6% SL) and a narrower interorbital (IOD: 19.5%–27.1% vs. 27.3%–28% HL).
Biology and ecology: Most specimens of P. stiassnyae were collected in forested habitats over mud and plant debris in tributaries of the Mfimi River. The rivers where specimens of P. stiassnyae have been collected are characterized by a humic, moderately acidic (pH 4.1–5.3), and dark-brown water with low conductivity (10–50 μS/cm) and low concentrations of dissolved solids (TDS: 10–30 mg/L). These observations, combined with the species body colouration, suggest that P. stiassnyae is adapted to forested habitats, muddy, humic, and dark-brown waters of the Mfimi River tributaries.
Etymology: P. stiassnyae is named after Melanie L. J. Stiassny (MLJS) of the AMHN. MLJS is the initiator of the AMNH Congo Project that resulted in significant documentation and an improved systematic, biological, and evolutionary understanding of the Congo River basin ichthyofauna with an extensive collection deposited at the AMNH, the University of Kinshasa, and the University of Marien Ngouabi. Additionally, MLJS trained and continues to train numerous Congolese ichthyologists, including the authors of the present paper. We dedicate this species to her outstanding work and commitment to biodiscovery and conservation in the Congo River basin.
Myriam Y. Modimo, Maxwell J. Bernt, Raoul J. C. Monsembula Iyaba, José J. M. M. Mbimbi and Tobit L. D. Liyandja. 2024. Parauchenoglanis stiassnyae (Siluriformes: Auchenoglanididae): A New Species of Giraffe Catfish from Mfimi-Lukenie Basin, central Africa, Democratic Republic of Congo. Journal of Fish Biology. DOI: doi.org/10.1111/jfb.15885
x.com/MJBernt/status/1818665684739535207
==========================
Parauchenoglanis stiassnyae
Modimo, Bernt, Monsembula Iyaba, Mbimbi & Liyandja, 2024
DOI: 10.1111/jfb.15885
x.com/MJBernt
Abstract
A new, distinctively short-bodied giraffe catfish of Parauchenoglanis is described from the Ndzaa River, a small left-bank tributary of the Mfimi-Lukenie basin in the Central basin of the Congo River in the Democratic Republic of the Congo. The new species can be distinguished from all congeners by having 29 or fewer (vs. 33 or more) total vertebrae. It can further be distinguished from all congeners, except Parauchenoglanis zebratus Sithole et al., 2023 and Parauchenoglanis ngamensis (Boulenger 1911), by having 13 or 14 (vs. 16 or more) pre-anal vertebrae. The species is endemic to the Mfimi River basin, where it has been collected mainly in blackwater tributaries.
Keywords: Congo basin, CT scan, DNA barcoding, morpholog,y Ndzaa River, Parauchenoglanis
Parauchenoglanis stiassnyae sp. nov.
Photographs of preserved (a) holotype (AMNH 278139 in lateral view) and (b–d) paratype (AMNH 278165, 68.1 mm standard length [SL], respectively, in dorsal, lateral, and ventral views).
Scale bar: 1 cm.
Parauchenoglanis stiassnyae, sp. nov.
Diagnosis: P. stiassnyae is distinguished from all congeners by having 28–29 vertebrae (vs. 33 or more). P. stiassnyae is also distinguished from all congeners by the possession of 13–14 pre-anal vertebrae (vs. 15 or more) except for Parauchenoglanis zebratus (14–17) and Parauchenoglanis ngamensis (13, holotype). The new species can further be distinguished from P. cf. punctatus_L3, P. balayi, P. longiceps, P. pantherinus, P. punctatus, and P. ubangensis by a narrower supraoccipital process–nuchal plate interdistance (1.4%–2.9% vs. >3% HL); from P. cf. punctatus_L3, P. guttatus, P. longiceps, P. pantherinus, and P. punctatus by a wider orbital HW (64.7%–76.2% vs. 54.9%–63.9% HL); from P. guttatus, P. longiceps, and P. ubangensis by a wider mouth (37.8%–50.8% vs. 25.9%–35.7% HL); from P. guttatus, P. punctatus, P. ubangensis, and P. zebratus by a wider premaxillary toothplate (12.9%–18.6% vs. 6.6%–12.5% HL); from P. guttatus, P. longiceps, P. pantherinus, and P. zebratus by a wider head (HW: 70.1%–81.1% vs. 58.9%–69.3% HL); from P. balayi and P. pantherinus by a shorter dorsal-fin spine (10.8%–16% vs. 16.1%–18.8% SL); from P. guttatus and P. pantherinus by a smaller orbital diameter (9.5%–14.2% vs. 14.4%–16.9% HL) and a wider interpectoral distance (16.7%–21.4% vs. 15.3%–16.6% SL); from P. balayi, P. ngamensis (holotype), and P. ubangensis by a shorter adipose-fin–caudal-fin interdistance (2.7%–5.2% vs. 6.2%–10.5% SL); and from P. balayi by a longer head (HL: 31.3%–35% vs. 28.1%–30.6% SL) and a narrower interorbital (IOD: 19.5%–27.1% vs. 27.3%–28% HL).
Biology and ecology: Most specimens of P. stiassnyae were collected in forested habitats over mud and plant debris in tributaries of the Mfimi River. The rivers where specimens of P. stiassnyae have been collected are characterized by a humic, moderately acidic (pH 4.1–5.3), and dark-brown water with low conductivity (10–50 μS/cm) and low concentrations of dissolved solids (TDS: 10–30 mg/L). These observations, combined with the species body colouration, suggest that P. stiassnyae is adapted to forested habitats, muddy, humic, and dark-brown waters of the Mfimi River tributaries.
Etymology: P. stiassnyae is named after Melanie L. J. Stiassny (MLJS) of the AMHN. MLJS is the initiator of the AMNH Congo Project that resulted in significant documentation and an improved systematic, biological, and evolutionary understanding of the Congo River basin ichthyofauna with an extensive collection deposited at the AMNH, the University of Kinshasa, and the University of Marien Ngouabi. Additionally, MLJS trained and continues to train numerous Congolese ichthyologists, including the authors of the present paper. We dedicate this species to her outstanding work and commitment to biodiscovery and conservation in the Congo River basin.
Myriam Y. Modimo, Maxwell J. Bernt, Raoul J. C. Monsembula Iyaba, José J. M. M. Mbimbi and Tobit L. D. Liyandja. 2024. Parauchenoglanis stiassnyae (Siluriformes: Auchenoglanididae): A New Species of Giraffe Catfish from Mfimi-Lukenie Basin, central Africa, Democratic Republic of Congo. Journal of Fish Biology. DOI: doi.org/10.1111/jfb.15885
x.com/MJBernt/status/1818665684739535207
==========================
Phylogeographic Patterns of Cyphocharax (Characiformes: Curimatidae) from trans-Andean Rivers and northward expansion to lower Central America
Cyphocharax spp.
in Melo, Conde-Saldaña, Villa-Navarro, McMahan et Oliveira, 2024.
DOI: 10.1111/jfb.15777
x.com/TheFSBI
Abstract
Phylogenetic analyses of mitochondrial and nuclear data of 31 specimens of Cyphocharax from trans-Andean rivers support the presence of one lineage of Cyphocharax aspilos in Lago Maracaibo and three cryptic lineages of Cyphocharax magdalenae: (1) Cauca-Magdalena and Ranchería, (2) León and Atrato, and (3) Chucunaque-Tuira, Santa María, and Chiriquí basins of Central America. Results suggest that the Serranía del Perijá facilitated Late Miocene cladogenetic events, whereas post-Isthmian C. magdalenae expansion was enabled by gene flow across the lower Magdalena valley and Central American lowlands. Time-calibrated phylogenetics indicate that the C. magdalenae colonized lower Central America in the Pliocene (3.7 MYA; Ma), the divergence Atrato-Magdalena occurred in Late Pliocene (3.0 Ma) and the split Ranchería-Magdalena during the Middle Pleistocene (1.3 Ma). Updated geographic distribution data support the hypothesis that the Cordillera de Talamanca functions as a barrier to northward expansion of C. magdalenae in Central America.
Keywords: Characiformes, Magdalena, Maracaibo, Ostariophysi, Serranía del Perijá, Talamanca
Bruno F. Melo, Cristhian C. Conde-Saldaña, Francisco A. Villa-Navarro, Caleb D. McMahan and Claudio Oliveira. 2024. Phylogeographic Patterns of Cyphocharax from trans-Andean Rivers and northward expansion to lower Central America (Teleostei, Curimatidae). Journal of Fish Biology. 105(1); 314-325. DOI: doi.org/10.1111/jfb.15777
x.com/TheFSBI/status/1813834913109422246
==========================
Cyphocharax spp.
in Melo, Conde-Saldaña, Villa-Navarro, McMahan et Oliveira, 2024.
DOI: 10.1111/jfb.15777
x.com/TheFSBI
Abstract
Phylogenetic analyses of mitochondrial and nuclear data of 31 specimens of Cyphocharax from trans-Andean rivers support the presence of one lineage of Cyphocharax aspilos in Lago Maracaibo and three cryptic lineages of Cyphocharax magdalenae: (1) Cauca-Magdalena and Ranchería, (2) León and Atrato, and (3) Chucunaque-Tuira, Santa María, and Chiriquí basins of Central America. Results suggest that the Serranía del Perijá facilitated Late Miocene cladogenetic events, whereas post-Isthmian C. magdalenae expansion was enabled by gene flow across the lower Magdalena valley and Central American lowlands. Time-calibrated phylogenetics indicate that the C. magdalenae colonized lower Central America in the Pliocene (3.7 MYA; Ma), the divergence Atrato-Magdalena occurred in Late Pliocene (3.0 Ma) and the split Ranchería-Magdalena during the Middle Pleistocene (1.3 Ma). Updated geographic distribution data support the hypothesis that the Cordillera de Talamanca functions as a barrier to northward expansion of C. magdalenae in Central America.
Keywords: Characiformes, Magdalena, Maracaibo, Ostariophysi, Serranía del Perijá, Talamanca
Bruno F. Melo, Cristhian C. Conde-Saldaña, Francisco A. Villa-Navarro, Caleb D. McMahan and Claudio Oliveira. 2024. Phylogeographic Patterns of Cyphocharax from trans-Andean Rivers and northward expansion to lower Central America (Teleostei, Curimatidae). Journal of Fish Biology. 105(1); 314-325. DOI: doi.org/10.1111/jfb.15777
x.com/TheFSBI/status/1813834913109422246
==========================
Sciadonus alphacrucis • A New Species of the rare deep-sea Genus Sciadonus Garman, 1899 (Ophidiiformes: Bythitidae) from off Brazil, with a discussion of the evolution of troglomorphism and miniaturization in the aphyonid clade
Sciadonus alphacrucis
Melo, Gomes, Møller & Nielsen, 2022
DOI: 10.1016/j.dsr.2021.103684
Highlights:
• A new species of the rare genus Sciadonus is discovered from Brazilian waters.
• Highly specialized reproductive apparatus enables internal fertilization and viviparity in a deep-sea fish.
• The depletion of sunlight resulted on convergent evolution of troglomorphic traits in deep-sea fishes and cave fishes.
• Human activities of oil and natural gas exploration, fisheries and littering may be impacting rare deep-sea species.
Abstract
A new species of the rare, deep-sea genus Sciadonus Garman, 1899 (Bythitidae) is described based on two specimens obtained by the Brazilian R/V Alpha Crucis on the continental slope off São Paulo State, Southeastern Brazil, western South Atlantic. It differs from its congeners by the combination of the following characters: body pale lacking dark pigmentation except for on female claspers; a pair of dermal tissue flaps anteriorly on lower jaw; pelvic-fin rays present; precaudal vertebrae 39 or 40 and total vertebrae 74 or 75. The key to the species of Sciadonus is updated. A discussion of the presence and differentiation between troglomorphic and miniature characteristics among the species in the aphyonid clade is provided and compared with other bythitids.
Keywords: Aphyonid clade, Continental slope, Western South Atlantic, R/V Alpha Crucis
Sciadonus alphacrucis sp. n. ; western South Atlantic, São Paulo State, off Ilhabela, 794 m depth
MZUSP 125949, holotype, female, 82.7 mm SL
MZUSP 125950, paratype, male, 60.3 mm SL.
Order Ophidiiformes Berg, 1937.
Family Bythitidae Gill, 1861.
Sciadonus alphacrucis n. sp.
Etymology: The specific name honors the Brazilian R/V Alpha Crucis. A noun in apposition.
Marcelo Roberto Souto de Melo, Amand Alves Gomes, Peter Rask Møller and Jørgen G. Nielsen. 2022. A New Species of the rare deep-sea Genus Sciadonus Garman, 1899 (Teleostei, Bythitidae) from off Brazil, with a discussion of the evolution of troglomorphism and miniaturization in the aphyonid clade. Deep Sea Research Part I: Oceanographic Research Papers. 180, 103684. DOI: 10.1016/j.dsr.2021.103684
instagram.com/p/CYmsVeWPHYL
==========================
Sciadonus alphacrucis
Melo, Gomes, Møller & Nielsen, 2022
DOI: 10.1016/j.dsr.2021.103684
Highlights:
• A new species of the rare genus Sciadonus is discovered from Brazilian waters.
• Highly specialized reproductive apparatus enables internal fertilization and viviparity in a deep-sea fish.
• The depletion of sunlight resulted on convergent evolution of troglomorphic traits in deep-sea fishes and cave fishes.
• Human activities of oil and natural gas exploration, fisheries and littering may be impacting rare deep-sea species.
Abstract
A new species of the rare, deep-sea genus Sciadonus Garman, 1899 (Bythitidae) is described based on two specimens obtained by the Brazilian R/V Alpha Crucis on the continental slope off São Paulo State, Southeastern Brazil, western South Atlantic. It differs from its congeners by the combination of the following characters: body pale lacking dark pigmentation except for on female claspers; a pair of dermal tissue flaps anteriorly on lower jaw; pelvic-fin rays present; precaudal vertebrae 39 or 40 and total vertebrae 74 or 75. The key to the species of Sciadonus is updated. A discussion of the presence and differentiation between troglomorphic and miniature characteristics among the species in the aphyonid clade is provided and compared with other bythitids.
Keywords: Aphyonid clade, Continental slope, Western South Atlantic, R/V Alpha Crucis
Sciadonus alphacrucis sp. n. ; western South Atlantic, São Paulo State, off Ilhabela, 794 m depth
MZUSP 125949, holotype, female, 82.7 mm SL
MZUSP 125950, paratype, male, 60.3 mm SL.
Order Ophidiiformes Berg, 1937.
Family Bythitidae Gill, 1861.
Sciadonus alphacrucis n. sp.
Etymology: The specific name honors the Brazilian R/V Alpha Crucis. A noun in apposition.
Marcelo Roberto Souto de Melo, Amand Alves Gomes, Peter Rask Møller and Jørgen G. Nielsen. 2022. A New Species of the rare deep-sea Genus Sciadonus Garman, 1899 (Teleostei, Bythitidae) from off Brazil, with a discussion of the evolution of troglomorphism and miniaturization in the aphyonid clade. Deep Sea Research Part I: Oceanographic Research Papers. 180, 103684. DOI: 10.1016/j.dsr.2021.103684
instagram.com/p/CYmsVeWPHYL
==========================
Hypostomus cari • Integrative taxonomy clarifies the armoured catfish Hypostomus pusarum (Starks) species complex (Siluriformes: Loricariidae) and reveals A New Species in the drainages of Northeastern Brazil
Hypostomus cari
Lustosa-Costa, Ramos, Zawadzki, Jacobina & Lima, 2024
DOI: 10.1093/zoolinnean/zlae059
x.com/ZoolJLinnSoc
Abstract
Hypostomus is the most species-rich genus within the family Loricariidae and is widely distributed throughout the Neotropical region. Nonetheless, the diversity and distribution of these species have still large knowledge gaps. This scenario is more significant in some regions, such as the northeast of Brazil. In this region, the first species of the genus, H. pusarum, was described in the Northeast Caatinga and Costal Drainages ecoregion. Six congeners were subsequently described in the same ecoregion, all sharing the same colour pattern making them difficult to distinguish. All of them are collectively referred to as the H. pusarum complex. The present work seeks to clarify the diversity that constitutes the H. pusarum complex through an integrative study using molecular and morphological data. The results indicate that H. carvalhoi, H. jaguribensis, H. nudiventris, H. papariae, and H. salgadae are all junior synonyms of H. pusarum. However, one of the morphotypes that occurs in the Parnaíba River is a new species that differs from the others by the absence of a developed medial buccal papilla and the presence of a pre-anal plate. The data provided here highlight the importance of integrative taxonomy for assessing diversity in complex and diverse groups in the Neotropics.
cascudos, DNA barcode, Neotropical fish, new species, Parnaíba River
Hypostomus cari sp. nov.
Silvia Yasmin Lustosa-Costa, Telton Pedro Anselmo Ramos, Cláudio Henrique Zawadzki, Uedson Pereira Jacobina and Sergio Maia Queiroz Lima. 2024. Integrative taxonomy clarifies the armoured catfish Hypostomus pusarum (Starks) species complex (Siluriformes: Loricariidae) and reveals A New Species in the drainages of Northeastern Brazil. Zoological Journal of the Linnean Society. 201(3); zlae059, DOI: doi.org/10.1093/zoolinnean/zlae059
x.com/ZoolJLinnSoc/status/1813166947200102676
==========================
Hypostomus cari
Lustosa-Costa, Ramos, Zawadzki, Jacobina & Lima, 2024
DOI: 10.1093/zoolinnean/zlae059
x.com/ZoolJLinnSoc
Abstract
Hypostomus is the most species-rich genus within the family Loricariidae and is widely distributed throughout the Neotropical region. Nonetheless, the diversity and distribution of these species have still large knowledge gaps. This scenario is more significant in some regions, such as the northeast of Brazil. In this region, the first species of the genus, H. pusarum, was described in the Northeast Caatinga and Costal Drainages ecoregion. Six congeners were subsequently described in the same ecoregion, all sharing the same colour pattern making them difficult to distinguish. All of them are collectively referred to as the H. pusarum complex. The present work seeks to clarify the diversity that constitutes the H. pusarum complex through an integrative study using molecular and morphological data. The results indicate that H. carvalhoi, H. jaguribensis, H. nudiventris, H. papariae, and H. salgadae are all junior synonyms of H. pusarum. However, one of the morphotypes that occurs in the Parnaíba River is a new species that differs from the others by the absence of a developed medial buccal papilla and the presence of a pre-anal plate. The data provided here highlight the importance of integrative taxonomy for assessing diversity in complex and diverse groups in the Neotropics.
cascudos, DNA barcode, Neotropical fish, new species, Parnaíba River
Hypostomus cari sp. nov.
Silvia Yasmin Lustosa-Costa, Telton Pedro Anselmo Ramos, Cláudio Henrique Zawadzki, Uedson Pereira Jacobina and Sergio Maia Queiroz Lima. 2024. Integrative taxonomy clarifies the armoured catfish Hypostomus pusarum (Starks) species complex (Siluriformes: Loricariidae) and reveals A New Species in the drainages of Northeastern Brazil. Zoological Journal of the Linnean Society. 201(3); zlae059, DOI: doi.org/10.1093/zoolinnean/zlae059
x.com/ZoolJLinnSoc/status/1813166947200102676
==========================
Aequidens pirilampo • A New Species of Aequidens (Cichliformes: Cichlidae) from the rio Paraguai basin, Brazil
Aequidens pirilampo
R.C. Oliveira, Tencatt, Deprá, Britzke, C. Oliveira & Graça, 2024
DOI: 10.1590/1982-0224-2023-0106
Abstract
Morphological and molecular data support the description of a new Aequidens species from the upper rio Correntes, considered herein as endemic to the upper rio Paraguai basin in the Cerrado biome in Brazil. The new species is distinguished from all congeners, except from A. plagiozonatus by having anteriorly oblique dark brown flank bars vs. vertical flank bars, and is additionally distinguished from some congeners by showing a discontinuous lateral band and presence of a dark cheek spot. The new species differs from Aequidens plagiozonatus by having the profile of the dorsal part of head almost straight (in lateral view), with a conspicuous concavity at the interorbital, and by the longer length of upper and lower jaws. Furthermore, delimitation analyses based on mitochondrial data provide additional support for the validity of the species. Our study data also revealed the occurrence, and consequently the first record, of A. plagiozonatus in the upper rio Araguaia basin, which was most likely driven by headwater capture events.
Keywords: Cerrado biome; DNA barcode; Molecular data; Morphological data; Species delimitation
Aequidens pirilampo, living specimens photographed just after capture in the rio Comprido, rio Paraguai River basin, 17°32’04.8”S 54°25’36.6”W, uncatalogued. Photos by L. F. C. Tencatt.
Aequidens pirilampo, new species
Diagnosis. Aequidens pirilampo is distinguished from all congeners, except A. plagiozonatus, by having anteriorly oblique dark brown flank bars (vs. vertical). The new species differs from A. plagiozonatus by having the dorsal head contour, from the tip of the snout to the vertical through the posterior margin of the eye, almost straight, except for a conspicuous concavity at the interorbital region (Fig. 2) (vs. dorsal head contour convex, with a subtle concavity at the interorbital region in occasional specimens), by having longer lower jaw (40.2–46.9% HL and 16.7–18.5% SL vs. 35.2–39.3% HL and 13.2–15.2% SL in A. plagiozonatus), and longer upper jaw, (12.2–15.1% SL vs. 9.3–12.1% SL in A. plagiozonatus). Additionally, A. pirilampo is distinguished from its congeners, except A. chimantanus Inger, 1956, A. diadema, A. epae, A. mauesanus Kullander, 1997, A. michaeli, A. patricki Kullander, 1984, A. plagiozonatus, A. potaroensis Eigenmann, 1912, and A. tubicen Kullander & Ferreira, 1991, by having a discontinuous lateral band in fixed specimens (vs. continuous). ...
Etymology. The specific epithet “pirilampo” means firefly in the popular Portuguese naming in the region the new species occurs. It is a bioluminescent Coleoptera very common in this region. These insects emit an intense green light, which alludes to the color pattern in life displayed by the new species. A noun in apposition.
Collecting sites of Aequidens pirilampo, showing (A) the ribeirão Comprido, its type-locality, (B) a stream with unknown name, and (C) the córrego de Cima, all tributaries of the rio Correntes in the border region of Mato Grosso and Mato Grosso do Sul states, Central Brazil. Photo (A) by LFCT, (B) by Heriberto Gimênes Jr., and (C) by Hans Evers.
Rianne Caroline de Oliveira, Luiz Fernando Caserta Tencatt, Gabriel de Carvalho Deprá, Ricardo Britzke, Claudio Oliveira and Weferson Júnio da Graça. 2024. A New Species of Aequidens (Cichliformes: Cichlidae) from the rio Paraguai basin, Brazil. Neotrop. ichthyol. 22 (2); DOI: doi.org/10.1590/1982-0224-2023-0106
Resumo: Dados morfológicos e moleculares apoiam a descrição de uma nova espécie de Aequidens do alto rio Correntes, considerada aqui como uma espécie endêmica da bacia do alto rio Paraguai, no bioma Cerrado no Brasil. A nova espécie distingue-se de todas as congêneres, exceto de Aequidens plagiozonatus, por apresentar barras laterais marrom-escuras oblíquas em direção anterodorsal vs. barras verticais nos flancos. Além disso, distingue-se de algumas espécies por apresentar uma faixa lateral descontínua e pela presença de uma mancha escura na porção entre a órbita e a margem preopercular. A nova espécie difere de A. plagiozonatus por apresentar o perfil da parte dorsal da cabeça (em vista lateral) aproximadamente reta, com uma concavidade conspícua na porção interorbital, e pelo maior comprimento das maxilas superior e inferior. Além disso, análises de delimitação baseadas em dados mitocondriais oferecem evidência a favor da validade da espécie. Nossos dados também revelaram a ocorrência e, consequentemente, o primeiro registro de A. plagiozonatus na bacia do alto rio Araguaia, provavelmente devido a eventos de captura de cabeceiras.
Palavras chave: Bioma Cerrado; Dados moleculares; Dados morfológicos; Delimitação de espécies; DNA barcode
==========================
Aequidens pirilampo
R.C. Oliveira, Tencatt, Deprá, Britzke, C. Oliveira & Graça, 2024
DOI: 10.1590/1982-0224-2023-0106
Abstract
Morphological and molecular data support the description of a new Aequidens species from the upper rio Correntes, considered herein as endemic to the upper rio Paraguai basin in the Cerrado biome in Brazil. The new species is distinguished from all congeners, except from A. plagiozonatus by having anteriorly oblique dark brown flank bars vs. vertical flank bars, and is additionally distinguished from some congeners by showing a discontinuous lateral band and presence of a dark cheek spot. The new species differs from Aequidens plagiozonatus by having the profile of the dorsal part of head almost straight (in lateral view), with a conspicuous concavity at the interorbital, and by the longer length of upper and lower jaws. Furthermore, delimitation analyses based on mitochondrial data provide additional support for the validity of the species. Our study data also revealed the occurrence, and consequently the first record, of A. plagiozonatus in the upper rio Araguaia basin, which was most likely driven by headwater capture events.
Keywords: Cerrado biome; DNA barcode; Molecular data; Morphological data; Species delimitation
Aequidens pirilampo, living specimens photographed just after capture in the rio Comprido, rio Paraguai River basin, 17°32’04.8”S 54°25’36.6”W, uncatalogued. Photos by L. F. C. Tencatt.
Aequidens pirilampo, new species
Diagnosis. Aequidens pirilampo is distinguished from all congeners, except A. plagiozonatus, by having anteriorly oblique dark brown flank bars (vs. vertical). The new species differs from A. plagiozonatus by having the dorsal head contour, from the tip of the snout to the vertical through the posterior margin of the eye, almost straight, except for a conspicuous concavity at the interorbital region (Fig. 2) (vs. dorsal head contour convex, with a subtle concavity at the interorbital region in occasional specimens), by having longer lower jaw (40.2–46.9% HL and 16.7–18.5% SL vs. 35.2–39.3% HL and 13.2–15.2% SL in A. plagiozonatus), and longer upper jaw, (12.2–15.1% SL vs. 9.3–12.1% SL in A. plagiozonatus). Additionally, A. pirilampo is distinguished from its congeners, except A. chimantanus Inger, 1956, A. diadema, A. epae, A. mauesanus Kullander, 1997, A. michaeli, A. patricki Kullander, 1984, A. plagiozonatus, A. potaroensis Eigenmann, 1912, and A. tubicen Kullander & Ferreira, 1991, by having a discontinuous lateral band in fixed specimens (vs. continuous). ...
Etymology. The specific epithet “pirilampo” means firefly in the popular Portuguese naming in the region the new species occurs. It is a bioluminescent Coleoptera very common in this region. These insects emit an intense green light, which alludes to the color pattern in life displayed by the new species. A noun in apposition.
Collecting sites of Aequidens pirilampo, showing (A) the ribeirão Comprido, its type-locality, (B) a stream with unknown name, and (C) the córrego de Cima, all tributaries of the rio Correntes in the border region of Mato Grosso and Mato Grosso do Sul states, Central Brazil. Photo (A) by LFCT, (B) by Heriberto Gimênes Jr., and (C) by Hans Evers.
Rianne Caroline de Oliveira, Luiz Fernando Caserta Tencatt, Gabriel de Carvalho Deprá, Ricardo Britzke, Claudio Oliveira and Weferson Júnio da Graça. 2024. A New Species of Aequidens (Cichliformes: Cichlidae) from the rio Paraguai basin, Brazil. Neotrop. ichthyol. 22 (2); DOI: doi.org/10.1590/1982-0224-2023-0106
Resumo: Dados morfológicos e moleculares apoiam a descrição de uma nova espécie de Aequidens do alto rio Correntes, considerada aqui como uma espécie endêmica da bacia do alto rio Paraguai, no bioma Cerrado no Brasil. A nova espécie distingue-se de todas as congêneres, exceto de Aequidens plagiozonatus, por apresentar barras laterais marrom-escuras oblíquas em direção anterodorsal vs. barras verticais nos flancos. Além disso, distingue-se de algumas espécies por apresentar uma faixa lateral descontínua e pela presença de uma mancha escura na porção entre a órbita e a margem preopercular. A nova espécie difere de A. plagiozonatus por apresentar o perfil da parte dorsal da cabeça (em vista lateral) aproximadamente reta, com uma concavidade conspícua na porção interorbital, e pelo maior comprimento das maxilas superior e inferior. Além disso, análises de delimitação baseadas em dados mitocondriais oferecem evidência a favor da validade da espécie. Nossos dados também revelaram a ocorrência e, consequentemente, o primeiro registro de A. plagiozonatus na bacia do alto rio Araguaia, provavelmente devido a eventos de captura de cabeceiras.
Palavras chave: Bioma Cerrado; Dados moleculares; Dados morfológicos; Delimitação de espécies; DNA barcode
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Stiphodon chlorestes • A New Species of sicydiine Goby (Gobiiformes: Oxudercidae) from Taiwan and Luzon
Stiphodon chlorestes
Jhuang, Dimaquibo & Liao, 2024
Green Hummingbird Goby | 青蜂枝牙鰕虎 || DOI: 10.1111/jfb.15852
facebook.com/WeiChengJhuang
Abstract
Stiphodon chlorestes sp. nov. is described based on seven specimens collected from Taiwan and Luzon. It is a large-sized Stiphodon species sharing the second dorsal-fin rays 9–10 and pectoral-fin rays 14–16 with similar-sized congeners. However, it differs from them by the wider interorbital width and almost complete lack of scales on the occipital region in males. In addition, the new species can be further distinguished from all congeners by seven to eight oval bands or a black longitudinal band on the lower body, black and white spots on pectoral fins, and a short red or orange line on posterior upper edge of caudal fin. Molecular analysis based on the 680-bp mitochondrial cytochrome oxidase subunit I (COI) fragments also supports it as a distinct species belonging to the “Stiphodon elegans group” and a sister group of the clade consisting of Stiphodon multisquamus and Stiphodon palawanensis.
Stiphodon chlorestes sp. nov.
Green hummingbird goby | 青蜂枝牙鰕虎
Wei-Cheng Jhuang, Al Casane Dimaquibo and Te-Yu Liao. 2024. Stiphodon chlorestes, A New Species of sicydiine Goby (Teleostei: Gobioidei) from Taiwan and Luzon. Journal of Fish Biology. DOI: 10.1111/jfb.15852
facebook.com/WeiChengJhuang/posts/3804582706427229
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Stiphodon chlorestes
Jhuang, Dimaquibo & Liao, 2024
Green Hummingbird Goby | 青蜂枝牙鰕虎 || DOI: 10.1111/jfb.15852
facebook.com/WeiChengJhuang
Abstract
Stiphodon chlorestes sp. nov. is described based on seven specimens collected from Taiwan and Luzon. It is a large-sized Stiphodon species sharing the second dorsal-fin rays 9–10 and pectoral-fin rays 14–16 with similar-sized congeners. However, it differs from them by the wider interorbital width and almost complete lack of scales on the occipital region in males. In addition, the new species can be further distinguished from all congeners by seven to eight oval bands or a black longitudinal band on the lower body, black and white spots on pectoral fins, and a short red or orange line on posterior upper edge of caudal fin. Molecular analysis based on the 680-bp mitochondrial cytochrome oxidase subunit I (COI) fragments also supports it as a distinct species belonging to the “Stiphodon elegans group” and a sister group of the clade consisting of Stiphodon multisquamus and Stiphodon palawanensis.
Stiphodon chlorestes sp. nov.
Green hummingbird goby | 青蜂枝牙鰕虎
Wei-Cheng Jhuang, Al Casane Dimaquibo and Te-Yu Liao. 2024. Stiphodon chlorestes, A New Species of sicydiine Goby (Teleostei: Gobioidei) from Taiwan and Luzon. Journal of Fish Biology. DOI: 10.1111/jfb.15852
facebook.com/WeiChengJhuang/posts/3804582706427229
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Sinobdella longitubulus • A New Species of Spiny Eel (Pisces: Mastacembelidae) from the Zhu-Jiang Basin, southern China, with A Note on the Type Locality of S. sinensis (Bleeker, 1870)
Sinobdella longitubulus Shan & Zhang,
in Shan, Li et Zhang, 2024.
长管华刺鳅 || DOI: 10.3897/BDJ.12.e123990
Abstract
Background: The spiny eel genus Sinobdella belongs to the family Mastacembelidae of the order Synbranchiformes. Kottelat and Lim (1994) utilised Rhynchobdella sinensis as the type species to propose the genus. Currently, it contains a single species widespread in eastern and southern China and northern Vietnam.
New information: Sinobdella longitubulus, a new species of spiny eel, is here described from the Xi-Jiang of the Zhu-Jiang Basin in Guangxi Zhuang Autonomous Region, southern China. It differs from the single congeneric species S. sinensis in having a more or less white-brown reticulated pattern on the flank, two tubular anterior nostrils longer than or equal to the rostral appendage, an anal fin heavily mottled with dark brown markings and white spots and bearing a narrow white distal margin; shorter pre-anal length; and fewer abdominal vertebrae. The validity of this new species is corroborated by its monophyly recovered in a COI gene-based phylogenetic analysis and its significant sequence divergence with S. sinensis. A note on the type locality of S. sinensis is also given; its type specimen is possibly from mountain streams of Jiangxi Province, in the lower Chang-Jiang Basin.
Keywords: Sinobdella, new species, taxonomy, Zhu-Jiang Basin
Sinobdella longitubulus, holotype, IHB 202303066738, 153.3 mm SL, dorsal (a), lateral (b) and ventral (c) views. China: Guangxi Province: Guigang City: Pingnan County: Lilia Village: Datong-Jiang, a stream tributary to Meng-Jiang flowing into Xi-Jiang of Zhu-Jiang basin.
Sinobdella longitubulus, IHB 202303066740, 148.7 mm SL, China: Guangxi Province: Guigang City: Pingnan County: Lilia Town: Datong-Jiang: Zhu-Jiang Basin;
Sinobdella longitubulus Shan & Zhang sp. nov.
Diagnosis: Sinobdella longitubulus is clearly distinguished from the single congeneric species (S. sinensis) by having a more or less white-brown reticulated pattern (vs. many dark brown vertical bars, with very narrow light yellow interspaces) on the flank (Fig. 2), two tubular anterior nostrils longer than or equal to (vs. shorter than) the rostral appendage (Fig. 3), an anal fin heavily mottled with dark brown markings and white spots and bearing a narrow white distal margin (vs. black with a relatively wide light white distal margin) (Fig. 2); shorter pre-anal length (53.3-56.2 vs. 56.3-60.6 % SL; see Fig. 4) and fewer abdominal vertebrae (32-33, mean = 32.9 vs. 34-36, mean = 35.1) (Table 1).
...
Etymology: The epithet name, used here as a noun, is derived from the Latin word longus (= long) and tubulus (= pipe), alluding to two longer tubes modified from anterior nostrils. The common Chinese name here suggested for this new species is “长管华刺鳅”.
Peng Shan, Guangyu Li and E Zhang. 2024. Sinobdella longitubulus, A New Species of Spiny Eel (Pisces, Mastacembelidae) from the Zhu-Jiang Basin, with A Note on the Type Locality of S. sinensis (Bleeker, 1870). Biodiversity Data Journal. 12: e123990. DOI: 10.3897/BDJ.12.e123990
==========================
Sinobdella longitubulus Shan & Zhang,
in Shan, Li et Zhang, 2024.
长管华刺鳅 || DOI: 10.3897/BDJ.12.e123990
Abstract
Background: The spiny eel genus Sinobdella belongs to the family Mastacembelidae of the order Synbranchiformes. Kottelat and Lim (1994) utilised Rhynchobdella sinensis as the type species to propose the genus. Currently, it contains a single species widespread in eastern and southern China and northern Vietnam.
New information: Sinobdella longitubulus, a new species of spiny eel, is here described from the Xi-Jiang of the Zhu-Jiang Basin in Guangxi Zhuang Autonomous Region, southern China. It differs from the single congeneric species S. sinensis in having a more or less white-brown reticulated pattern on the flank, two tubular anterior nostrils longer than or equal to the rostral appendage, an anal fin heavily mottled with dark brown markings and white spots and bearing a narrow white distal margin; shorter pre-anal length; and fewer abdominal vertebrae. The validity of this new species is corroborated by its monophyly recovered in a COI gene-based phylogenetic analysis and its significant sequence divergence with S. sinensis. A note on the type locality of S. sinensis is also given; its type specimen is possibly from mountain streams of Jiangxi Province, in the lower Chang-Jiang Basin.
Keywords: Sinobdella, new species, taxonomy, Zhu-Jiang Basin
Sinobdella longitubulus, holotype, IHB 202303066738, 153.3 mm SL, dorsal (a), lateral (b) and ventral (c) views. China: Guangxi Province: Guigang City: Pingnan County: Lilia Village: Datong-Jiang, a stream tributary to Meng-Jiang flowing into Xi-Jiang of Zhu-Jiang basin.
Sinobdella longitubulus, IHB 202303066740, 148.7 mm SL, China: Guangxi Province: Guigang City: Pingnan County: Lilia Town: Datong-Jiang: Zhu-Jiang Basin;
Sinobdella longitubulus Shan & Zhang sp. nov.
Diagnosis: Sinobdella longitubulus is clearly distinguished from the single congeneric species (S. sinensis) by having a more or less white-brown reticulated pattern (vs. many dark brown vertical bars, with very narrow light yellow interspaces) on the flank (Fig. 2), two tubular anterior nostrils longer than or equal to (vs. shorter than) the rostral appendage (Fig. 3), an anal fin heavily mottled with dark brown markings and white spots and bearing a narrow white distal margin (vs. black with a relatively wide light white distal margin) (Fig. 2); shorter pre-anal length (53.3-56.2 vs. 56.3-60.6 % SL; see Fig. 4) and fewer abdominal vertebrae (32-33, mean = 32.9 vs. 34-36, mean = 35.1) (Table 1).
...
Etymology: The epithet name, used here as a noun, is derived from the Latin word longus (= long) and tubulus (= pipe), alluding to two longer tubes modified from anterior nostrils. The common Chinese name here suggested for this new species is “长管华刺鳅”.
Peng Shan, Guangyu Li and E Zhang. 2024. Sinobdella longitubulus, A New Species of Spiny Eel (Pisces, Mastacembelidae) from the Zhu-Jiang Basin, with A Note on the Type Locality of S. sinensis (Bleeker, 1870). Biodiversity Data Journal. 12: e123990. DOI: 10.3897/BDJ.12.e123990
==========================
Macabi tojolabalensis • A new Mesozoic teleost of the subfamily Albulinae (Albuliformes: Albulidae) highlights the proto-Gulf of Mexico in the early Diversification of extant Bonefishes
Macabi tojolabalensis
L-Recinos, Cantalice, Caballero-Viñas & Alvarado-Ortega, 2023
DOI: 10.1080/14772019.2023.2223797
x.com/Cantalice_KM
Abstract
We present a new fossil species of the order Albuliformes, †Macabi tojolabalensis gen. et sp. nov., from Campanian outcrops of Chiapas state, south-eastern Mexico. The number of branchiostegal rays, a fusion of the lower hypural elements in the caudal-fin skeleton, and the two types of cycloid scales over the body are features that separate this new taxon from other members of the order. Its inclusion in a phylogenetic analysis including fossil and extant species shows that †Macabi tojolabalensis gen. et sp. nov. is closely related to the extant Albula vulpes. The biogeographical analysis shows four distinct regions of bonefish diversification during the Cretaceous and identifies the proto-Gulf of Mexico as an important place to understand the early divergence of living albuliformes.
Keywords: Albuliformes, Late Cretaceous, Mexico, systematics, biogeography, new species
Macabi tojolabalensis
Marleni L-Recinos, Kleyton M. Cantalice, Carmen Caballero-Viñas and Jesús Alvarado-Ortega. 2023. A new Mesozoic teleost of the subfamily Albulinae (Albuliformes: Albulidae) highlights the proto-Gulf of Mexico in the early diversification of extant bonefishes. Journal of Systematic Palaeontology. 21(1); 2223797. DOI: 10.1080/14772019.2023.2223797
x.com/Cantalice_KM/status/1678830357418766336
==========================
Macabi tojolabalensis
L-Recinos, Cantalice, Caballero-Viñas & Alvarado-Ortega, 2023
DOI: 10.1080/14772019.2023.2223797
x.com/Cantalice_KM
Abstract
We present a new fossil species of the order Albuliformes, †Macabi tojolabalensis gen. et sp. nov., from Campanian outcrops of Chiapas state, south-eastern Mexico. The number of branchiostegal rays, a fusion of the lower hypural elements in the caudal-fin skeleton, and the two types of cycloid scales over the body are features that separate this new taxon from other members of the order. Its inclusion in a phylogenetic analysis including fossil and extant species shows that †Macabi tojolabalensis gen. et sp. nov. is closely related to the extant Albula vulpes. The biogeographical analysis shows four distinct regions of bonefish diversification during the Cretaceous and identifies the proto-Gulf of Mexico as an important place to understand the early divergence of living albuliformes.
Keywords: Albuliformes, Late Cretaceous, Mexico, systematics, biogeography, new species
Macabi tojolabalensis
Marleni L-Recinos, Kleyton M. Cantalice, Carmen Caballero-Viñas and Jesús Alvarado-Ortega. 2023. A new Mesozoic teleost of the subfamily Albulinae (Albuliformes: Albulidae) highlights the proto-Gulf of Mexico in the early diversification of extant bonefishes. Journal of Systematic Palaeontology. 21(1); 2223797. DOI: 10.1080/14772019.2023.2223797
x.com/Cantalice_KM/status/1678830357418766336
==========================
Yunnanilus polylepis • A New Species of Yunnanilus (Cypriniformes: Nemacheilidae) from Yunnan, southwest China
Yunnanilus polylepis
Qin, Shao, Du & Wang, 2024
多鳞云南鳅 || DOI: 10.3897/zse.100.122962
Abstract
A new species of Yunnanilus is described from the Nanpanjiang River, Yunnan, China. The new species, Yunnanilus polylepis, can be distinguished from other species of Yunnanilus by the following combination of characteristics: Processus dentiformis absent; eye diameter smaller than interorbital width; outer gill raker absent and 10 inner gill rakers on first gill arch; whole trunk covered by scales; nine branched dorsal-fin rays; 10 or 11 branched pectoral-fin rays; six branched pelvic-fin rays. Despite our phylogenetic analysis, which sheds light on the complex relationships among Yunnanilus species, the majority of Yunnanilus species are restricted to more localized environments and habitats. It is urgent to address the environmental threats that jeopardize their survival, especially given their generally restricted distribution.
Key Words: Loach, mitochondrial gene, morphology, Nanpanjiang River, taxonomy
Morphometric characters of Yunnanilus polylepis sp. nov.
A–C. Lateral, dorsal, and ventral views of female, holotype KIZ2023000009; D–F. Lateral, dorsal, and ventral views of male, paratype KIZ2023000041; G–H. Living photo of female and male; I. Location of anterior and posterior nostrils.
Yunnanilus polylepis sp. nov.
Diagnosis: The new species is distinguished from all other members of the genus based on the following characters: whole trunk covered by scales; processus dentiformis absent; eye diameter smaller than interorbital width; nine branched dorsal-fin rays; 10 or 11 branched pectoral-fin rays; six branched pelvic-fin rays; outer gill raker absent and 10 inner gill rakers on first gill arch.
Etymology: The specific name polylepis is derived from the characteristic of being entirely covered by scales Gender: Masculine. We suggest the Chinese and English common names as “多鳞云南鳅” and “densely scaled Yunnan loach,” respectively.
Zhi-Xian Qin, Wei-han Shao, Li-Na Du and Zhen-Xing Wang. 2024. A New Species of Yunnanilus (Cypriniformes, Nemacheilidae) from Yunnan, southwest China. Zoosystematics and Evolution. 100(2): 747-754. DOI: 10.3897/zse.100.122962
==========================
Yunnanilus polylepis
Qin, Shao, Du & Wang, 2024
多鳞云南鳅 || DOI: 10.3897/zse.100.122962
Abstract
A new species of Yunnanilus is described from the Nanpanjiang River, Yunnan, China. The new species, Yunnanilus polylepis, can be distinguished from other species of Yunnanilus by the following combination of characteristics: Processus dentiformis absent; eye diameter smaller than interorbital width; outer gill raker absent and 10 inner gill rakers on first gill arch; whole trunk covered by scales; nine branched dorsal-fin rays; 10 or 11 branched pectoral-fin rays; six branched pelvic-fin rays. Despite our phylogenetic analysis, which sheds light on the complex relationships among Yunnanilus species, the majority of Yunnanilus species are restricted to more localized environments and habitats. It is urgent to address the environmental threats that jeopardize their survival, especially given their generally restricted distribution.
Key Words: Loach, mitochondrial gene, morphology, Nanpanjiang River, taxonomy
Morphometric characters of Yunnanilus polylepis sp. nov.
A–C. Lateral, dorsal, and ventral views of female, holotype KIZ2023000009; D–F. Lateral, dorsal, and ventral views of male, paratype KIZ2023000041; G–H. Living photo of female and male; I. Location of anterior and posterior nostrils.
Yunnanilus polylepis sp. nov.
Diagnosis: The new species is distinguished from all other members of the genus based on the following characters: whole trunk covered by scales; processus dentiformis absent; eye diameter smaller than interorbital width; nine branched dorsal-fin rays; 10 or 11 branched pectoral-fin rays; six branched pelvic-fin rays; outer gill raker absent and 10 inner gill rakers on first gill arch.
Etymology: The specific name polylepis is derived from the characteristic of being entirely covered by scales Gender: Masculine. We suggest the Chinese and English common names as “多鳞云南鳅” and “densely scaled Yunnan loach,” respectively.
Zhi-Xian Qin, Wei-han Shao, Li-Na Du and Zhen-Xing Wang. 2024. A New Species of Yunnanilus (Cypriniformes, Nemacheilidae) from Yunnan, southwest China. Zoosystematics and Evolution. 100(2): 747-754. DOI: 10.3897/zse.100.122962
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Reconstructing an Ancient Fish: Three-dimensional Skeletal Restoration of the Head of Mawsonia (Sarcopterygii: Actinistia) using CT Scan, and an adjusted model for body size estimation in fossil coelacanths
Head of Mawsonia (Sarcopterygii, Actinistia)
in Toriño, Dutel, Soto, Norbis, Ezquerra & Perea, 2024.
DOI: 10.1111/joa.14054
x.com/PabloTorino4
Abstract
Mawsonia constitutes one of the most conspicuous fossil coelacanth taxa, due to its unique anatomy and possible maximum body size. It typifies Mesozoic coelacanth morphology, before the putative disappearance of the group in the fossil record. In this work, the three-dimensional cranial anatomy and body size estimations of this genus are re-evaluated from a recently described specimen from Upper Jurassic deposits of Uruguay. The 3D restoration was performed directly on the material based on anatomical information provided by the living coelacanth Latimeria and previous two-dimensional restorations of the head of Mawsonia. The montage was then scanned with computed tomography and virtually adjusted to generate an interactive online resource for future anatomical, taxonomic and biomechanical research. In general terms, the model constitutes a tool to improve both the anatomical knowledge of this genus and its comparison with other coelacanths. It also facilitates the evaluation of possible evolutionary trends and the discussion of particular features with potential palaeobiological implications, such as the anterior position of the eye and the development of the pseudomaxillary fold. Regarding the body size, a previous model for body size estimation based on the gular plate was submitted to OLS, RMA, segmented linear and PGLS regressions (including the evaluation of regression statistics, variance analysis, t-tests and residual analysis). The results point to a power relationship between gular and total lengths showing a better support than a simple linear relationship. The new resulting equations were applied to the studied individual and are provided for future estimates. Although an isometric evolutionary growth cannot be rejected with the available evidence, additional models developed with other bones will be necessary to evaluate possible hidden evolutionary allometric trends in this group of fishes, thus avoiding overestimates.
Keywords: 3D reconstruction, body size, coelacanths, computed tomography, Mawsonia
Pablo Toriño, Hugo Dutel, Matías Soto, Walter Norbis, Víctor Ezquerra and Daniel Perea. 2024. Reconstructing an Ancient Fish: Three-dimensional Skeletal Restoration of the Head of Mawsonia (Sarcopterygii, Actinistia) using CT Scan, and an adjusted model for body size estimation in fossil coelacanths. Journal of Anatomy. DOI: 10.1111/joa.14054
x.com/PabloTorino4/status/1791310290782494804
Head of Mawsonia (Sarcopterygii, Actinistia)
in Toriño, Dutel, Soto, Norbis, Ezquerra & Perea, 2024.
DOI: 10.1111/joa.14054
x.com/PabloTorino4
Abstract
Mawsonia constitutes one of the most conspicuous fossil coelacanth taxa, due to its unique anatomy and possible maximum body size. It typifies Mesozoic coelacanth morphology, before the putative disappearance of the group in the fossil record. In this work, the three-dimensional cranial anatomy and body size estimations of this genus are re-evaluated from a recently described specimen from Upper Jurassic deposits of Uruguay. The 3D restoration was performed directly on the material based on anatomical information provided by the living coelacanth Latimeria and previous two-dimensional restorations of the head of Mawsonia. The montage was then scanned with computed tomography and virtually adjusted to generate an interactive online resource for future anatomical, taxonomic and biomechanical research. In general terms, the model constitutes a tool to improve both the anatomical knowledge of this genus and its comparison with other coelacanths. It also facilitates the evaluation of possible evolutionary trends and the discussion of particular features with potential palaeobiological implications, such as the anterior position of the eye and the development of the pseudomaxillary fold. Regarding the body size, a previous model for body size estimation based on the gular plate was submitted to OLS, RMA, segmented linear and PGLS regressions (including the evaluation of regression statistics, variance analysis, t-tests and residual analysis). The results point to a power relationship between gular and total lengths showing a better support than a simple linear relationship. The new resulting equations were applied to the studied individual and are provided for future estimates. Although an isometric evolutionary growth cannot be rejected with the available evidence, additional models developed with other bones will be necessary to evaluate possible hidden evolutionary allometric trends in this group of fishes, thus avoiding overestimates.
Keywords: 3D reconstruction, body size, coelacanths, computed tomography, Mawsonia
Pablo Toriño, Hugo Dutel, Matías Soto, Walter Norbis, Víctor Ezquerra and Daniel Perea. 2024. Reconstructing an Ancient Fish: Three-dimensional Skeletal Restoration of the Head of Mawsonia (Sarcopterygii, Actinistia) using CT Scan, and an adjusted model for body size estimation in fossil coelacanths. Journal of Anatomy. DOI: 10.1111/joa.14054
x.com/PabloTorino4/status/1791310290782494804
==========================
Nannocharax skeltoni • A New Species of Banded Nannocharax (Cithariniformes: Distichodontidae) from the Luapula River Basin, Zambia, Africa
Nannocharax skeltoni
Jerep, Vari, Dillman & Santana, 2024
DOI: 10.1643/i2023041
x.com/IchsAndHerps
Abstract
A new species of Nannocharax is described from the Luongo and Kalungwishi Rivers, tributaries of the Luapula River in the northeastern region of Zambia. The new species differs from its congeners by a combination of characters, such as the body coloration pattern formed by a series of one-scale-wide vertical bars, a small caudal-peduncle spot surrounded by a light clear area at the base of the middle caudal-fin rays, and a low number of scales in the circumpeduncular series and lateral line series. The new species is also distinguished from other members of the Nannocharax multifasciatus species-group by genetic distances ranging from 10.3% to 11.6% with DNA barcoding. Likewise, distance and coalescent molecular species delimitation approaches recovered the new species as an independent operational taxonomic unit. Newly generated hypotheses of phylogenetic relationships based on maximum likelihood and Bayesian inference for the new taxon are provided.
Nannocharax skeltoni, CUMV 100101, 22.6 mm SL, holotype, Zambia, Luapula, Luongo River drainage, Lufubo River falls ...
Nannocharax skeltoni, new species
Etymology.--The species name, skeltoni, is in honor of Professor Paul Harvey Skelton of the South African Institute for Aquatic Biodiversity, in recognition of his outstanding contributions to our knowledge of the diversity and biogeography of African fishes. A genitive noun
Fernando C. Jerep, Richard P. Vari, Casey B. Dillman and C. David de Santana. 2024. A New Species of Banded Nannocharax from the Luapula River Basin, Zambia, Africa (Cithariniformes: Distichodontidae). Ichthyology & Herpetology. 112(2):156-167. DOI: 10.1643/i2023041
x.com/IchsAndHerps/status/1796046263835648257
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Nannocharax skeltoni
Jerep, Vari, Dillman & Santana, 2024
DOI: 10.1643/i2023041
x.com/IchsAndHerps
Abstract
A new species of Nannocharax is described from the Luongo and Kalungwishi Rivers, tributaries of the Luapula River in the northeastern region of Zambia. The new species differs from its congeners by a combination of characters, such as the body coloration pattern formed by a series of one-scale-wide vertical bars, a small caudal-peduncle spot surrounded by a light clear area at the base of the middle caudal-fin rays, and a low number of scales in the circumpeduncular series and lateral line series. The new species is also distinguished from other members of the Nannocharax multifasciatus species-group by genetic distances ranging from 10.3% to 11.6% with DNA barcoding. Likewise, distance and coalescent molecular species delimitation approaches recovered the new species as an independent operational taxonomic unit. Newly generated hypotheses of phylogenetic relationships based on maximum likelihood and Bayesian inference for the new taxon are provided.
Nannocharax skeltoni, CUMV 100101, 22.6 mm SL, holotype, Zambia, Luapula, Luongo River drainage, Lufubo River falls ...
Nannocharax skeltoni, new species
Etymology.--The species name, skeltoni, is in honor of Professor Paul Harvey Skelton of the South African Institute for Aquatic Biodiversity, in recognition of his outstanding contributions to our knowledge of the diversity and biogeography of African fishes. A genitive noun
Fernando C. Jerep, Richard P. Vari, Casey B. Dillman and C. David de Santana. 2024. A New Species of Banded Nannocharax from the Luapula River Basin, Zambia, Africa (Cithariniformes: Distichodontidae). Ichthyology & Herpetology. 112(2):156-167. DOI: 10.1643/i2023041
x.com/IchsAndHerps/status/1796046263835648257
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Two new species of the armored catfish genus Panaqolus (Siluriformes, Loricariidae) from the Ecuadorian AmazonPISCESANDEAN PIEDMONTDIVERSITYFRESHWATER FISHESNEOTROPICSTAXONOMYAbstractCurrently four described species of genus Panaqolus have been reported from the Amazon River basin in Ecuador: P. albomaculatus (Kanazawa 1958), P. dentex (Günther 1868), P. gnomus (Schaefer & Stewart 1993) and P. nocturnus (Schaefer & Stewart 1993). Revision of specimens deposited at the fish collection of Museo de la Escuela Politécnica Nacional (MEPN), Quito, indicated the presence of two additional species, both new to science: P. orcesi n. sp. and P. pantostiktos n. sp. The new species are similar to each other, and to P. albomaculatus and P. nix Cramer & Rapp Py-Daniel 2015 in having the head, body, and fins covered with light dots. Diagnostic characters comprise differences in color pattern, including size and density of light dots on head, body, and fins; as well as various morphometric characters. Apparently, both new species reach larger sizes than previously described species of Panaqolus. The two new species can be included in the subgenus Panafilus (Lujan et al. 2017); they come from the Tigre and Napo River basins, two isolated tributaries in the western Amazon.
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CHyphessobrycon wadai • A Name for the ‘Blueberry Tetra’, An Aquarium Trade popular Species of Hyphessobrycon Durbin (Characiformes: Characidae) from Amazon Basin, Brazil
Hyphessobrycon wadai
Marinho, Dagosta, Camelier & Oyakawa, 2016
DOI: 10.1111/jfb.12991
Abstract
A new species of Hyphessobrycon is described from a tributary of the upper Rio Tapajós, Amazon basin, Mato Grosso, Brazil. Its exuberant colour in life, with blue to purple body and red fins, is appreciated in the aquarium trade. Characters to diagnose the new species from all congeners are the presence of a single humeral blotch, absence of a distinct caudal-peduncle blotch, absence of a well-defined dark mid-lateral stripe on body, the presence of 16–18 branched anal-fin rays, nine branched dorsal-fin rays and six branched pelvic-fin rays. A brief comment on fish species descriptions solely based on aquarium material and its consequence for conservation policies is provided.
Keywords: freshwater fish; Hyphessobrycon coelestinus; Rio Juruena; Rio Tapajós; taxonomy
Hyphessobrycon wadai
Etymology -- The specific name, wadai, is a patronym that honours Luiz Wada, ornamental fish breeder and enthusiastic aquarist, in recognition of his help in many scientific researches with fishes.
Distribution — Hyphessobrycon wadai is known from tributaries of the Rio do Sangue, affluent of the Rio Juruena, upper Rio Tapajós basin, Brazil.
M. M. F. Marinho , F. C. P. Dagosta , P. Camelier and O. T. Oyakawa. 2016. A Name for the ‘Blueberry Tetra’, An Aquarium Trade popular Species of Hyphessobrycon Durbin (Characiformes, Characidae), with Comments on fish species descriptions lacking accurate Type Locality. Journal of Fish Biology. [Special Issue: Fish and Aquatic Habitat Conservation in South America]. 89(1); 510–521. DOI: 10.1111/jfb.12991
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Hyphessobrycon wadai
Marinho, Dagosta, Camelier & Oyakawa, 2016
DOI: 10.1111/jfb.12991
Abstract
A new species of Hyphessobrycon is described from a tributary of the upper Rio Tapajós, Amazon basin, Mato Grosso, Brazil. Its exuberant colour in life, with blue to purple body and red fins, is appreciated in the aquarium trade. Characters to diagnose the new species from all congeners are the presence of a single humeral blotch, absence of a distinct caudal-peduncle blotch, absence of a well-defined dark mid-lateral stripe on body, the presence of 16–18 branched anal-fin rays, nine branched dorsal-fin rays and six branched pelvic-fin rays. A brief comment on fish species descriptions solely based on aquarium material and its consequence for conservation policies is provided.
Keywords: freshwater fish; Hyphessobrycon coelestinus; Rio Juruena; Rio Tapajós; taxonomy
Hyphessobrycon wadai
Etymology -- The specific name, wadai, is a patronym that honours Luiz Wada, ornamental fish breeder and enthusiastic aquarist, in recognition of his help in many scientific researches with fishes.
Distribution — Hyphessobrycon wadai is known from tributaries of the Rio do Sangue, affluent of the Rio Juruena, upper Rio Tapajós basin, Brazil.
M. M. F. Marinho , F. C. P. Dagosta , P. Camelier and O. T. Oyakawa. 2016. A Name for the ‘Blueberry Tetra’, An Aquarium Trade popular Species of Hyphessobrycon Durbin (Characiformes, Characidae), with Comments on fish species descriptions lacking accurate Type Locality. Journal of Fish Biology. [Special Issue: Fish and Aquatic Habitat Conservation in South America]. 89(1); 510–521. DOI: 10.1111/jfb.12991
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Liobagrus chenhaojuni • A New Species of Liobagrus Hilgendorf, 1878 (Siluriformes: Amblycipitidae) from the lower Changjiang River basin in southeast China
Liobagrus chenhaojuni Chen, Guo & Wu,
in Chen, Guo, Dai, X.-C. Huang, J.-H. Huang, Jiang, Ouyang, Wen et Wu, 2024.
浙江䱀 || DOI: 10.3897/zse.100.122472
Abstract
A new catfish species, Liobagrus chenhaojuni Chen, Guo & Wu, sp. nov., is described from the Tiaoxi River, a tributary of Taihu Lake, located in Zhejiang Province, China. This description is based on morphological characteristics and phylogenetic analysis. This species belongs to a group defined by the presence of a smooth posterior edge of the pectoral-fin spine and can be distinguished from other species in the group by a unique combination of characteristics, including: an upper jaw longer than the lower jaw; maxillary barbels reaching the middle of the pectoral fin; irregular blotches present on the lateral body; a rounded caudal-fin with a length ranging from 16.5% to 19.9% of the standard length; 39 to 41 post-Weberian vertebrae; and 15 to 17 anal-fin rays. The validity of this new species is further supported by the molecular phylogenetic analysis based on Cytb sequences.
Key Words: catfish, phylogeny, taxonomy, Zhejiang Province
Liobagrus chenhaojuni sp. nov. A–C. Dorsal, lateral, and ventral view of holotype (24_NCU_XPWU_Y01); D. Dorsal view of pectoral-fin spine of paratype (22_NCU_XPWU_Y31). Arrows show the anus.
Living specimens of Liobagrus chenhaojuni sp. nov. and its similar congeneric species. A, B. Liobagrus chenhaojuni sp. nov.; C. Liobagrus chenhaojuni sp. nov. albino individual;
D. L. styani; E. L. anguillicauda; F. L. brevispina; G. dorsal view of pectoral-fin spine of L. brevispina.
Liobagrus chenhaojuni Chen, Guo & Wu, sp. nov.
Diagnosis: Liobagrus chenhaojuni sp. nov. is a member of the group defined by the presence of a smooth posterior edge of the pectoral-fin spine (i.e., L. reinii, L. formosanus, L. styani, L. nantoensis, L. anguillicauda, L. marginatoides, and L. aequilabris). It can be distinguished from all other species in this group by the following characteristics: the upper jaw is longer than the lower jaw (vs. equal in L. aequilabris and L. formosanus; shorter in L. marginatoides); the maxillary barbels reach the middle of the pectoral fin (vs. reach the pectoral-fin insertion in L. styani, L. reinii, and L. nantoensis); presence of irregular blotches on the lateral body (vs. absence in L. formosanus, L. nantoensis, L. anguillicauda, L. marginatoides, and L. aequilabris); the caudal fin is rounded (vs. sub-truncate in L. marginatoides); the caudal fin length ranges from 16.5% to 19.9% standard length (vs. 13.1–16.2 in L. styani, 20.3–27.0 in L. anguillicauda and 20.1–26.9 in L. aequilabris); it possesses 39–41 post-Weberian vertebrae (vs. 35–37 in L. aequilabris), the anal-fin rays range from 15 to 17 (vs. 12 in L. nantoensis) (Table 3).
Etymology: This species is named after Mr. Hao-Jun Chen, who assisted in the field survey.
Vernacular name: 浙江䱀 (Pinyin: zhe jiang yang).
Zhong-Guang Chen, Yan-Shu Guo, Yu-Ting Dai, Xiao-Chen Huang, Jun-Hao Huang, Jiao Jiang, Shan Ouyang, An-Xiang Wen and Xiao-Ping Wu. 2024. A New Species of Liobagrus Hilgendorf, 1878 (Teleostei, Siluriformes, Amblycipitidae) from the lower Changjiang River basin in southeast China. Zoosystematics and Evolution. 100(2): 555-563. DOI: 10.3897/zse.100.122472
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Liobagrus chenhaojuni Chen, Guo & Wu,
in Chen, Guo, Dai, X.-C. Huang, J.-H. Huang, Jiang, Ouyang, Wen et Wu, 2024.
浙江䱀 || DOI: 10.3897/zse.100.122472
Abstract
A new catfish species, Liobagrus chenhaojuni Chen, Guo & Wu, sp. nov., is described from the Tiaoxi River, a tributary of Taihu Lake, located in Zhejiang Province, China. This description is based on morphological characteristics and phylogenetic analysis. This species belongs to a group defined by the presence of a smooth posterior edge of the pectoral-fin spine and can be distinguished from other species in the group by a unique combination of characteristics, including: an upper jaw longer than the lower jaw; maxillary barbels reaching the middle of the pectoral fin; irregular blotches present on the lateral body; a rounded caudal-fin with a length ranging from 16.5% to 19.9% of the standard length; 39 to 41 post-Weberian vertebrae; and 15 to 17 anal-fin rays. The validity of this new species is further supported by the molecular phylogenetic analysis based on Cytb sequences.
Key Words: catfish, phylogeny, taxonomy, Zhejiang Province
Liobagrus chenhaojuni sp. nov. A–C. Dorsal, lateral, and ventral view of holotype (24_NCU_XPWU_Y01); D. Dorsal view of pectoral-fin spine of paratype (22_NCU_XPWU_Y31). Arrows show the anus.
Living specimens of Liobagrus chenhaojuni sp. nov. and its similar congeneric species. A, B. Liobagrus chenhaojuni sp. nov.; C. Liobagrus chenhaojuni sp. nov. albino individual;
D. L. styani; E. L. anguillicauda; F. L. brevispina; G. dorsal view of pectoral-fin spine of L. brevispina.
Liobagrus chenhaojuni Chen, Guo & Wu, sp. nov.
Diagnosis: Liobagrus chenhaojuni sp. nov. is a member of the group defined by the presence of a smooth posterior edge of the pectoral-fin spine (i.e., L. reinii, L. formosanus, L. styani, L. nantoensis, L. anguillicauda, L. marginatoides, and L. aequilabris). It can be distinguished from all other species in this group by the following characteristics: the upper jaw is longer than the lower jaw (vs. equal in L. aequilabris and L. formosanus; shorter in L. marginatoides); the maxillary barbels reach the middle of the pectoral fin (vs. reach the pectoral-fin insertion in L. styani, L. reinii, and L. nantoensis); presence of irregular blotches on the lateral body (vs. absence in L. formosanus, L. nantoensis, L. anguillicauda, L. marginatoides, and L. aequilabris); the caudal fin is rounded (vs. sub-truncate in L. marginatoides); the caudal fin length ranges from 16.5% to 19.9% standard length (vs. 13.1–16.2 in L. styani, 20.3–27.0 in L. anguillicauda and 20.1–26.9 in L. aequilabris); it possesses 39–41 post-Weberian vertebrae (vs. 35–37 in L. aequilabris), the anal-fin rays range from 15 to 17 (vs. 12 in L. nantoensis) (Table 3).
Etymology: This species is named after Mr. Hao-Jun Chen, who assisted in the field survey.
Vernacular name: 浙江䱀 (Pinyin: zhe jiang yang).
Zhong-Guang Chen, Yan-Shu Guo, Yu-Ting Dai, Xiao-Chen Huang, Jun-Hao Huang, Jiao Jiang, Shan Ouyang, An-Xiang Wen and Xiao-Ping Wu. 2024. A New Species of Liobagrus Hilgendorf, 1878 (Teleostei, Siluriformes, Amblycipitidae) from the lower Changjiang River basin in southeast China. Zoosystematics and Evolution. 100(2): 555-563. DOI: 10.3897/zse.100.122472
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Eustomias robertsi • A New Species of Eustomias (Nominostomias) (Stomiiformes: Stomiidae) from the Kermadec Ridge—Tonga Trench Region, western South Pacific Ocean, with Notes on the barbel morphology of E. trewavasae
Eustomias robertsi
Stewart, Kenaley & Sutton, 2024
DOI: 10.11646/zootaxa.5458.1.5
Abstract
A new species of dragonfish Eustomias (Nominostomias) robertsi is described from the western South Pacific Ocean. The new species, the first record of a member of Eustomias (Nominostomias) Group III (sensu Gibbs et al. 1983) from the region, it is most similar to Eustomias suluensis in barbel morphology. However, it has a smaller proximal and distal bulb distance, the smallest distal inter–bulb value in the group, and much longer terminal filaments.
Comments are also provided on the morphology of the diagnostic features on the barbel of Eustomias trewavasae, including an important character overlooked in the original description of the species. The barbel morphology is redescribed taking this into account.
A brief observation is made recording the first record of the subgenus Triclonostomias from the western South Pacific Ocean.
Key words: Taxonomy, marine fish, deep-sea, identification, dragonfish
Eustomias robertsi n. sp. holotype, NMNZ P.013765.; 232.1 mm SL. Illustration: Michelle Freeborn.
Teeth of Eustomias robertsi n. sp. holotype, NMNZ P.013765. Fixed teeth (black), remaining teeth depressible. Illustration by Michelle Freeborn.
Freshly caught paratype of Eustomias robertsi n. sp. NMNZ P. 058340; 144.6 mm SL. Photo Carl Struthers/Thom Linley.
Eustomias (Nominostomias) robertsi sp. nov.
Diagnosis: The new species is diagnosed from others in Eustomias (Nominostomias) Group III by the combination of the barbel morphology of: A very small distance between proximal and distal bulbs (0.1–0.2 % SL; 0.01–0.07 times distal bulb length), and three long terminal filaments, longest 30.4–42% SL.
Andrew L. Stewart, Christopher P. Kenaley and Tracy Sutton. 2024. A New Species of Eustomias (Nominostomias) (Stomiiformes: Stomiidae) from the Kermadec Ridge—Tonga Trench Region, western South Pacific Ocean, with Notes on the barbel morphology of E. trewavasae. Zootaxa. 5458(1); 93-107. DOI: 10.11646/zootaxa.5458.1.5
เขียนโดย pskhun ที่ 11:09 AM
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ป้ายกำกับ: 'Open Access', 2024, Actinopterygii, Deep sea, Ecology, Ichthyology - Fish, Marine, Ocean: Pacific, patronym, Phylogenetics, Taxonomy, Teleostei, Zootaxa
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Eustomias robertsi
Stewart, Kenaley & Sutton, 2024
DOI: 10.11646/zootaxa.5458.1.5
Abstract
A new species of dragonfish Eustomias (Nominostomias) robertsi is described from the western South Pacific Ocean. The new species, the first record of a member of Eustomias (Nominostomias) Group III (sensu Gibbs et al. 1983) from the region, it is most similar to Eustomias suluensis in barbel morphology. However, it has a smaller proximal and distal bulb distance, the smallest distal inter–bulb value in the group, and much longer terminal filaments.
Comments are also provided on the morphology of the diagnostic features on the barbel of Eustomias trewavasae, including an important character overlooked in the original description of the species. The barbel morphology is redescribed taking this into account.
A brief observation is made recording the first record of the subgenus Triclonostomias from the western South Pacific Ocean.
Key words: Taxonomy, marine fish, deep-sea, identification, dragonfish
Eustomias robertsi n. sp. holotype, NMNZ P.013765.; 232.1 mm SL. Illustration: Michelle Freeborn.
Teeth of Eustomias robertsi n. sp. holotype, NMNZ P.013765. Fixed teeth (black), remaining teeth depressible. Illustration by Michelle Freeborn.
Freshly caught paratype of Eustomias robertsi n. sp. NMNZ P. 058340; 144.6 mm SL. Photo Carl Struthers/Thom Linley.
Eustomias (Nominostomias) robertsi sp. nov.
Diagnosis: The new species is diagnosed from others in Eustomias (Nominostomias) Group III by the combination of the barbel morphology of: A very small distance between proximal and distal bulbs (0.1–0.2 % SL; 0.01–0.07 times distal bulb length), and three long terminal filaments, longest 30.4–42% SL.
Andrew L. Stewart, Christopher P. Kenaley and Tracy Sutton. 2024. A New Species of Eustomias (Nominostomias) (Stomiiformes: Stomiidae) from the Kermadec Ridge—Tonga Trench Region, western South Pacific Ocean, with Notes on the barbel morphology of E. trewavasae. Zootaxa. 5458(1); 93-107. DOI: 10.11646/zootaxa.5458.1.5
เขียนโดย pskhun ที่ 11:09 AM
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ป้ายกำกับ: 'Open Access', 2024, Actinopterygii, Deep sea, Ecology, Ichthyology - Fish, Marine, Ocean: Pacific, patronym, Phylogenetics, Taxonomy, Teleostei, Zootaxa
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[PaleoOrnithology • 2017] Exceptional Preservation of Soft Tissue in A New Specimen of Eoconfuciusornis and Its Biological Implications
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Abstract The genus Ischnothyreus Simon, 1893 from Java and Sumatra is revised with the description of seven new species from Java...
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Hyphessobrycon citrus • Redescription of Hyphessobrycon cachimbensis (Characiformes: Characidae) with the Description of A New congener from the Serra do Cachimbo, Brazil
Hyphessobrycon citrus
Marinho & Dagosta, 2024
DOI: 10.1590/1982-0224-2023-0127
Abstract
The Serra do Cachimbo is a highland area at the southeastern portion of the Amazon Forest drained by the headwaters of tributaries of rios Xingu and Tapajós. It is known as an area of high level of endemism of fish, low species diversity, and very few taxa with broad distribution in the other parts of the Amazon. Despite its biogeographical importance, there are still many poorly sampled areas. Four expeditions to the region yielded in the rediscovery of a poorly known, endemic species, Hyphessobrycon cachimbensis, and the discovery of a similar, allopatric undescribed congener, frequently misidentified as H. cachimbensis. We provided the redescription of H. cachimbensis and the description of the new species. Both can be differentiated from most congeners by having a conspicuous longitudinal dark stripe on body and anal-fin base convex in males, due to thicker musculature insertion in the region. Other diagnostic features are mostly related to counts of scales and fin rays.
Keywords: Endemism; Ostariophysi; Rio Tapajós; Rio Xingu; Tetra
Hyphessobrycon citrus, Brazil, Pará State, rio Tapajós basin, rio Teles Pires drainage, tributary of rio Braço Norte. A. MZUSP 128236, holotype, 38.0 mm SL, male; B. MZUSP 101429, paratype, 39.4 mm SL, female.
Hyphessobrycon citrus, new species
Diagnosis. Hyphessobrycon citrus can be distinguished from its congeners, except H. cachimbensis, H. chiribiquete, H. comodoro, H. cyanotaenia, H. fernandezi, H. melanostichos, H. nigricinctus, H. paucilepis, H. petricolus, H. piranga, H. psittacus, H. scholzei, H. sovichthys, H. stegemanni, H. taphorni, H. tuyensis, and H. vilmae,by the presence of a well-defined, relatively narrow dark midlateral stripe on body, from immediately behind the opercular opening to the tip of middle caudal-fin rays (vs. longitudinal stripe absent, stripe starting approximately at vertical through the dorsal-fin origin, or midlateral dark stripe becoming blurred towards the caudal peduncle). It can be distinguished from the aforementioned species, except H. cachimbensis, H. chiribiquete, H. comodoro, H. cyanotaenia, H. melanostichos, H. nigricinctus, and H. petricolus, by the presence of a humeral spot (vs. absence). Hyphessobrycon citrus can be distinguished from H. cachimbensis, H. comodoro, H. cyanotaenia, and H. melanostichos by having the longitudinal black stripe starting immediately behind the opercle (vs. starting at the posterior margin of orbit), from H. chiribiquete, H. nigricinctus and from H. cachimbensis by having 14–17 anal-fin rays (vs. 18 or more), and from H. petricolus by having 14 horizontal scale rows around caudal peduncle (vs. 12) and non-symphyseal teeth of the premaxillary inner row with 7 to 9 cusps (vs. 3 to 5). The yellow citrus coloration and a vivid colored red eye in life also help distinguishing H. citrus from congeners.
Etymology. The specific epithet comes from the Latin “citrus”, referring to its bright yellow coloration similar to several citrus fruits. A noun in apposition.
Manoela Maria Ferreira Marinho and Fernando Cesar Paiva Dagosta. 2024. Redescription of Hyphessobrycon cachimbensis (Characiformes: Characidae) with the Description of A New congener from the Serra do Cachimbo, Brazil. Neotrop. ichthyol. 22 (2); DOI: 10.1590/1982-0224-2023-0127
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Hyphessobrycon citrus
Marinho & Dagosta, 2024
DOI: 10.1590/1982-0224-2023-0127
Abstract
The Serra do Cachimbo is a highland area at the southeastern portion of the Amazon Forest drained by the headwaters of tributaries of rios Xingu and Tapajós. It is known as an area of high level of endemism of fish, low species diversity, and very few taxa with broad distribution in the other parts of the Amazon. Despite its biogeographical importance, there are still many poorly sampled areas. Four expeditions to the region yielded in the rediscovery of a poorly known, endemic species, Hyphessobrycon cachimbensis, and the discovery of a similar, allopatric undescribed congener, frequently misidentified as H. cachimbensis. We provided the redescription of H. cachimbensis and the description of the new species. Both can be differentiated from most congeners by having a conspicuous longitudinal dark stripe on body and anal-fin base convex in males, due to thicker musculature insertion in the region. Other diagnostic features are mostly related to counts of scales and fin rays.
Keywords: Endemism; Ostariophysi; Rio Tapajós; Rio Xingu; Tetra
Hyphessobrycon citrus, Brazil, Pará State, rio Tapajós basin, rio Teles Pires drainage, tributary of rio Braço Norte. A. MZUSP 128236, holotype, 38.0 mm SL, male; B. MZUSP 101429, paratype, 39.4 mm SL, female.
Hyphessobrycon citrus, new species
Diagnosis. Hyphessobrycon citrus can be distinguished from its congeners, except H. cachimbensis, H. chiribiquete, H. comodoro, H. cyanotaenia, H. fernandezi, H. melanostichos, H. nigricinctus, H. paucilepis, H. petricolus, H. piranga, H. psittacus, H. scholzei, H. sovichthys, H. stegemanni, H. taphorni, H. tuyensis, and H. vilmae,by the presence of a well-defined, relatively narrow dark midlateral stripe on body, from immediately behind the opercular opening to the tip of middle caudal-fin rays (vs. longitudinal stripe absent, stripe starting approximately at vertical through the dorsal-fin origin, or midlateral dark stripe becoming blurred towards the caudal peduncle). It can be distinguished from the aforementioned species, except H. cachimbensis, H. chiribiquete, H. comodoro, H. cyanotaenia, H. melanostichos, H. nigricinctus, and H. petricolus, by the presence of a humeral spot (vs. absence). Hyphessobrycon citrus can be distinguished from H. cachimbensis, H. comodoro, H. cyanotaenia, and H. melanostichos by having the longitudinal black stripe starting immediately behind the opercle (vs. starting at the posterior margin of orbit), from H. chiribiquete, H. nigricinctus and from H. cachimbensis by having 14–17 anal-fin rays (vs. 18 or more), and from H. petricolus by having 14 horizontal scale rows around caudal peduncle (vs. 12) and non-symphyseal teeth of the premaxillary inner row with 7 to 9 cusps (vs. 3 to 5). The yellow citrus coloration and a vivid colored red eye in life also help distinguishing H. citrus from congeners.
Etymology. The specific epithet comes from the Latin “citrus”, referring to its bright yellow coloration similar to several citrus fruits. A noun in apposition.
Manoela Maria Ferreira Marinho and Fernando Cesar Paiva Dagosta. 2024. Redescription of Hyphessobrycon cachimbensis (Characiformes: Characidae) with the Description of A New congener from the Serra do Cachimbo, Brazil. Neotrop. ichthyol. 22 (2); DOI: 10.1590/1982-0224-2023-0127
==========================
Phylogenetic and Phylogeographic insights into Sri Lankan Killifishes (Teleostei: Cyprinodontiformes: Aplocheilidae)
Aplocheilus dayi phenotype (a) male and (b) female,
Aplocheilus werneri phenotype (c) male and (d) female,
Aplocheilus parvus (e) male and (f) female.
in Sudasinghe, Ranasinghe, Wijesooriya, Rüber et Meegaskumbura, 2024.
DOI: 10.1111/jfb.15792
facebook.com/HiranyaSud
Researchgate.net/publication/380732853
Phylogenetic and Phylogeographic insights into Sri Lankan Killifishes (Teleostei: Cyprinodontiformes: Aplocheilidae)ylogenetic and Phylogeographic insights into Sri Lankan Killifishes (Teleostei: Cyprinodontiformes: Aplocheilida
Abstract
Three nominal species of the killifish genus Aplocheilus are reported from the lowlands of Sri Lanka. Two of these, Aplocheilus dayi and Aplocheilus werneri, are considered endemic to the island, whereas Aplocheilus parvus is reported from both Sri Lanka and Peninsular India. Here, based on a collection from 28 locations in Sri Lanka, also including a dataset of Asian Aplocheilus downloaded from GenBank, we present a phylogeny constructed from the mitochondrial cytochrome b (cytb), mitochondrial cytochrome c oxidase subunit 1 (cox1), and nuclear recombination activating protein 1 (rag1), and investigate the interrelationships of the species of Aplocheilus in Sri Lanka. The endemic Sri Lankan aplocheilid clade comprising A. dayi and A. werneri is recovered as the sister group to the clade comprising A. parvus from Sri Lanka and Aplocheilus blockii from Peninsular India. The reciprocal monophyly of A. dayi and A. werneri is not supported in our molecular phylogeny. A. dayi and A. werneri display strong sexual dimorphism, but species-level differences are subtle, explained mostly by pigmentation patterns. Their phenotypes exhibit a parapatric distribution and may represent locally adapted forms of a single species. Alternatively, the present study does not rule out the possibility that A. dayi and A. werneri may represent an incipient species pair or that they have undergone introgression or hybridization in their contact zones. We provide evidence that the Nilwala-Gin region of southwestern Sri Lanka may have acted as a drought refugium for these fishes.
link facebook.com/Tharindu2010ac/posts/8468383033188002
facebook.com/KumuduWijesooriya90/posts/3806986412912229
facebook.com/HiranyaSud/posts/470590205478609
Researchgate.net/publication/380732853_Phylogenetic_phylogeographic_SriLankan_Aplocheilidae
==========================
Three nominal species of the killifish genus Aplocheilus are reported from the lowlands of Sri Lanka. Two of these, Aplocheilus dayi and Aplocheilus werneri, are considered endemic to the island, whereas Aplocheilus parvus is reported from both Sri Lanka and Peninsular India. Here, based on a collection from 28 locations in Sri Lanka, also including a dataset of Asian Aplocheilus downloaded from GenBank, we present a phylogeny constructed from the mitochondrial cytochrome b (cytb), mitochondrial cytochrome c oxidase subunit 1 (cox1), and nuclear recombination activating protein 1 (rag1), and investigate the interrelationships of the species of Aplocheilus in Sri Lanka. The endemic Sri Lankan aplocheilid clade comprising A. dayi and A. werneri is recovered as the sister group to the clade comprising A. parvus from Sri Lanka and Aplocheilus blockii from Peninsular India. The reciprocal monophyly of A. dayi and A. werneri is not supported in our molecular phylogeny. A. dayi and A. werneri display strong sexual dimorphism, but species-level differences are subtle, explained mostly by pigmentation patterns. Their phenotypes exhibit a parapatric distribution and may represent locally adapted forms of a single species. Alternatively, the present study does not rule out the possibility that A. dayi and A. werneri may represent an incipient species pair or that they have undergone introgression or hybridization in their contact zones. We provide evidence that the Nilwala-Gin region of southwestern Sri Lanka may have acted as a drought refugium for these fishes.
link facebook.com/Tharindu2010ac/posts/8468383033188002
facebook.com/KumuduWijesooriya90/posts/3806986412912229
facebook.com/HiranyaSud/posts/470590205478609
Researchgate.net/publication/380732853_Phylogenetic_phylogeographic_SriLankan_Aplocheilidae
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Rhinolepadichthys gen. nov. • A New Generic Name for the “Lepadichthys” lineatus complex (Gobiesocidae: Diademichthyinae) with A Rediagnosis of Discotrema, a senior synonym of Unguitrema, and Comments on their phylogenetic relationships
Representatives of diademichthyine clingfishes.
A Rhinolepadichthys lineatus (Oman); B Rhinolepadichthys geminus (Anilao, Philippines);
C Rhinolepadichthys geminus (Okinoerabu Islands, Amami Islands, Japan); D Discotrema crinophilum (Amami-oshima Island, Amami Islands, Japan: KPM-NR 78755);
E Lepadichthys frenatus (Lord Howe Island, Australia); F Diademichthys lineatus (Lembeh Strait, Indonesia: KPM-NR 147468).
in Fujiwara, Motomura, Summers & Conway, 2024.
DOI: 10.3897/vz.74.e113955
All images except F with sides reversed.
photos by J. Randall, J. Eyre and K. Uehara.
Abstract
Rhinolepadichthys, a new genus of the gobiesocid subfamily Diademichthyinae, is described for the “Lepadichthys” lineatus complex (including Rhinolepadichthys geminus comb. nov., R. heemstraorum comb. nov., R. lineatus comb. nov., and R. polyastrous comb. nov.). Detailed investigation of external morphology and osteological anatomy of the new genus and related genera suggests that Rhinolepadichthys represents the sister genus to Discotrema, based on the following putative synapomorphies: (1) presence of a hardened (potentially keratinized) cap on the surface of at least some disc papillae (vs. surface of disc papillae soft, without hardened cap); and (2) the anterolateral part of the ventral postcleithrum extended anteriorly as a well-developed rod-like process, its tip close to the base of pelvic-fin soft ray 4 (vs. only weakly pointed, or irregular). Compared with Discotrema, Rhinolepadichthys gen. nov. is distinguished by the presence of a row of 8–12 large papillae on the inner surface of the upper and lower lips (vs. inner surface of lips smooth, without distinct papillae); the absence (vs. presence) of a well-developed lateral process on the pterotic immediately posterior to the opening of the otic canal; the presence (vs. absence) of gill rakers on the anterior edge of ceratobranchials 1–3; the presence (vs. absence) of gill rakers on the posterior edge of ceratobranchial 4; having the upper pharyngeal teeth arranged in a loose patch on the ventral surface of the pharyngobranchial 3 toothplate, with tooth tips directed posteroventrally (vs. arranged in a single row along posteroventral edge of the pharyngobranchial 3 toothplate, with tooth tips directed posteriorly); features of the adhesive disc, including outline of disc papillae roughly hexagonal or ovoid and with a flattened surface (vs. outline circular, at least some with raised, dome-like surface); the absence (vs. presence) of a deep cavity at the center of disc region C; the absence (vs. presence) of three paired and one median cluster of small papillae (reminiscent of bunches of grapes) across the surface of the adhesive disc; and having the ventral postcleithrum entire, not divided into two separate, articulating elements (vs. ventral postcleithrum divided into an anterior and posterior element, separated via a specialized joint). Reexamination of materials of the poorly known genus Unguitrema, considered a close relative of Discotrema, revealed no morphological differences between the two genera. Unguitrema therefore represents a junior synonym of Discotrema.
Keywords: Clingfishes, Indo-Pacific, morphology, taxonomy, Teleostei
Representatives of diademichthyine clingfishes.
A Rhinolepadichthys lineatus (Oman: J. Randall); B Rhinolepadichthys geminus (Anilao, Philippines: J. Eyre);
C Rhinolepadichthys geminus (Okinoerabu Islands, Amami Islands, Japan: K. Uehara); D Discotrema crinophilum (Amami-oshima Island, Amami Islands, Japan: KPM-NR 78755, K. Uchino);
E Lepadichthys frenatus (Lord Howe Island, Australia: J. Eyre); F Diademichthys lineatus (Lembeh Strait, Indonesia: KPM-NR 147468, K. Uchino).
All images except F with sides reversed.
Rhinolepadichthys gen. nov.
Included species: The genus contains the following four valid species, previously included in the “Lepadichthys” lineatus complex by Fujiwara and Motomura (2021): Rhinolepadichthys geminus (Fujiwara and Motomura, 2021) comb. nov., Rhinolepadichthys heemstraorum (Fujiwara and Motomura, 2021) comb. nov., Rhinolepadichthys lineatus (Briggs, 1966) comb. nov., and Rhinolepadichthys polyastrous (Fujiwara and Motomura, 2021) comb. nov.
Etymology: The suffix rhino-, meaning nose, in combination with Lepadichthys, a genus of the Diademichthyinae. In reference to the pointed snout in members of this genus, which distinguishes the new genus from Lepadichthys (sensu stricto). Gender masculine.
Discotrema Briggs, 1976
Included species: The genus contains the following four valid species, Discotrema crinophilum Briggs, 1976, Discotrema monogrammum Craig & Randall, 2008, Discotrema nigrum (Fricke, 2014), comb. nov. (validity tentative, see below), and Discotrema zonatum Craig & Randall, 2008.
Kyoji Fujiwara, Hiroyuki Motomura, Adam P. Summers and Kevin W. Conway. 2024. A New Generic Name for the “Lepadichthys” lineatus complex with A Rediagnosis of Discotrema, a senior synonym of Unguitrema, and Comments on their phylogenetic relationships (Gobiesocidae: Diademichthyinae). Vertebrate Zoology. 74: 279-301. DOI: 10.3897/vz.74.e113955
==========================
Representatives of diademichthyine clingfishes.
A Rhinolepadichthys lineatus (Oman); B Rhinolepadichthys geminus (Anilao, Philippines);
C Rhinolepadichthys geminus (Okinoerabu Islands, Amami Islands, Japan); D Discotrema crinophilum (Amami-oshima Island, Amami Islands, Japan: KPM-NR 78755);
E Lepadichthys frenatus (Lord Howe Island, Australia); F Diademichthys lineatus (Lembeh Strait, Indonesia: KPM-NR 147468).
in Fujiwara, Motomura, Summers & Conway, 2024.
DOI: 10.3897/vz.74.e113955
All images except F with sides reversed.
photos by J. Randall, J. Eyre and K. Uehara.
Abstract
Rhinolepadichthys, a new genus of the gobiesocid subfamily Diademichthyinae, is described for the “Lepadichthys” lineatus complex (including Rhinolepadichthys geminus comb. nov., R. heemstraorum comb. nov., R. lineatus comb. nov., and R. polyastrous comb. nov.). Detailed investigation of external morphology and osteological anatomy of the new genus and related genera suggests that Rhinolepadichthys represents the sister genus to Discotrema, based on the following putative synapomorphies: (1) presence of a hardened (potentially keratinized) cap on the surface of at least some disc papillae (vs. surface of disc papillae soft, without hardened cap); and (2) the anterolateral part of the ventral postcleithrum extended anteriorly as a well-developed rod-like process, its tip close to the base of pelvic-fin soft ray 4 (vs. only weakly pointed, or irregular). Compared with Discotrema, Rhinolepadichthys gen. nov. is distinguished by the presence of a row of 8–12 large papillae on the inner surface of the upper and lower lips (vs. inner surface of lips smooth, without distinct papillae); the absence (vs. presence) of a well-developed lateral process on the pterotic immediately posterior to the opening of the otic canal; the presence (vs. absence) of gill rakers on the anterior edge of ceratobranchials 1–3; the presence (vs. absence) of gill rakers on the posterior edge of ceratobranchial 4; having the upper pharyngeal teeth arranged in a loose patch on the ventral surface of the pharyngobranchial 3 toothplate, with tooth tips directed posteroventrally (vs. arranged in a single row along posteroventral edge of the pharyngobranchial 3 toothplate, with tooth tips directed posteriorly); features of the adhesive disc, including outline of disc papillae roughly hexagonal or ovoid and with a flattened surface (vs. outline circular, at least some with raised, dome-like surface); the absence (vs. presence) of a deep cavity at the center of disc region C; the absence (vs. presence) of three paired and one median cluster of small papillae (reminiscent of bunches of grapes) across the surface of the adhesive disc; and having the ventral postcleithrum entire, not divided into two separate, articulating elements (vs. ventral postcleithrum divided into an anterior and posterior element, separated via a specialized joint). Reexamination of materials of the poorly known genus Unguitrema, considered a close relative of Discotrema, revealed no morphological differences between the two genera. Unguitrema therefore represents a junior synonym of Discotrema.
Keywords: Clingfishes, Indo-Pacific, morphology, taxonomy, Teleostei
Representatives of diademichthyine clingfishes.
A Rhinolepadichthys lineatus (Oman: J. Randall); B Rhinolepadichthys geminus (Anilao, Philippines: J. Eyre);
C Rhinolepadichthys geminus (Okinoerabu Islands, Amami Islands, Japan: K. Uehara); D Discotrema crinophilum (Amami-oshima Island, Amami Islands, Japan: KPM-NR 78755, K. Uchino);
E Lepadichthys frenatus (Lord Howe Island, Australia: J. Eyre); F Diademichthys lineatus (Lembeh Strait, Indonesia: KPM-NR 147468, K. Uchino).
All images except F with sides reversed.
Rhinolepadichthys gen. nov.
Included species: The genus contains the following four valid species, previously included in the “Lepadichthys” lineatus complex by Fujiwara and Motomura (2021): Rhinolepadichthys geminus (Fujiwara and Motomura, 2021) comb. nov., Rhinolepadichthys heemstraorum (Fujiwara and Motomura, 2021) comb. nov., Rhinolepadichthys lineatus (Briggs, 1966) comb. nov., and Rhinolepadichthys polyastrous (Fujiwara and Motomura, 2021) comb. nov.
Etymology: The suffix rhino-, meaning nose, in combination with Lepadichthys, a genus of the Diademichthyinae. In reference to the pointed snout in members of this genus, which distinguishes the new genus from Lepadichthys (sensu stricto). Gender masculine.
Discotrema Briggs, 1976
Included species: The genus contains the following four valid species, Discotrema crinophilum Briggs, 1976, Discotrema monogrammum Craig & Randall, 2008, Discotrema nigrum (Fricke, 2014), comb. nov. (validity tentative, see below), and Discotrema zonatum Craig & Randall, 2008.
Kyoji Fujiwara, Hiroyuki Motomura, Adam P. Summers and Kevin W. Conway. 2024. A New Generic Name for the “Lepadichthys” lineatus complex with A Rediagnosis of Discotrema, a senior synonym of Unguitrema, and Comments on their phylogenetic relationships (Gobiesocidae: Diademichthyinae). Vertebrate Zoology. 74: 279-301. DOI: 10.3897/vz.74.e113955
==========================
REGULAR ARTICLEGross morphology of the brain and some sense organs of subterranean pencil catfishes of the genus Ituglanis Costa and Bockmann, 1993 (Siluriformes, Trichomycteridae), with a discussion on sensory compensation versus preadaptation in subterranean fishes
Pedro P. Rizzato, Maria Elina Bichuette
First published: 11 February 2024
https://doi.org/10.1111/jfb.15676
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SHAREAbstractSubterranean organisms provide excellent opportunities to investigate morphological evolution, especially of sensory organs and structures and their processing areas in the central nervous system. We describe the gross morphology of the brain and some cephalic sensory organs (olfactory organ, eye, semicircular canals of the inner ear) and the swim bladder (a non-sensory accessory structure) of subterranean species of pencil catfishes of the genus Ituglanis Costa and Bockmann, 1993 (Siluriformes, Trichomycteridae) and compare them with an epigean species of the genus, Ituglanis goya Datovo, Aquino and Langeani, 2016. We compared qualitatively the size of the different brain regions and sense organs of the subterranean species with those of the epigean one, searching for modifications possibly associated with living in the subterranean environment. Our findings suggest that species of Ituglanis exhibit sensory characteristics that are preadaptive for the subterranean life, as only slight modifications were observed in the brains and sense organs of the subterranean species of the genus when compared with the epigean one. Because most subterranean fish species belong to lineages putatively preadapted for subterranean life, our results, discussed in the context of available information on the brain and sense organs of other subterranean species, help identify general trends for the evolution of the brain and sensory organs of subterranean fishes in general.
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Schindleria nana • A New extremely progenetic gobiid fish Species (Gobiiformes: Gobiidae) from Lizard Island, Great Barrier Reef, Australia
Schindleria nana
Ahnelt, Macek & Robitzch, 2024
DOI: 10.25225/jvb.23112
Abstract
Here, we describe a new species of Schindleria, Schindleria nana, from Lizard Island, Great Barrier Reef, Australia. The new species belongs to the long dorsal-fin type (LDF) of Schindleria and is the first very small (‘dwarf’) LDF species (< 13 mm TL) to be described. It is characterized by an elongate and narrow body; a dorsal fin longer than the anal fin (predorsal-fin length 63.3% of SL: preanal-fin length 72.1% of SL); a long, relatively narrow head (head width 46.2% of head length) with a straight profile; small and round eyes (24.9% of head length); a large postorbital distance (52% of head length); a narrow, slender pectoral radial plate (width at origin 46.4%, maximum width 57.0% of pectoral radial plate length); 16 dorsal-fin rays; 11-12 anal-fin rays; first anal-fin ray ventral to the sixth dorsal-fin ray; six procurrent rays gradually increasing in length, last ray elongated, twice the length of the penultimate ray; premaxilla with tiny, conical, densely set teeth; dentary with zero teeth in the holotype and with two teeth on the left dentary and five teeth on the right dentary in the adult paratype; females with few (approx. 4-7) but very large eggs (3.4-3.9% of SL); urogenital papilla inconspicuous, de facto just an urogenital opening; swim bladder not pigmented; black eyes; no other external pigmentation on the body.
KEYWORDS: Coral reefs, Indo-Pacific, Miniaturization, new species, progenesis, taxonomy
Holotype of Schindleria nana, AMS.I.23115-004, female, 9.0 mm SL; Australia, Queensland, Lizard Island.
an – anus, ug – urogenital opening. Black asterisk – position of first anal-fin ray, white asterisk – position of first dorsal-fin ray. Scale bar: 1 mm.
Schindleria nana
Diagnosis: The new species S. nana stands out from its congeners because it is the first small-sized species (< 10 mm SL) in the LDF species group and the first LDF Schindleria with only a few (4-7) and very large eggs (3.1-3.6% of SL) (Figs. 3, 4A). It differs from its congeners in the combination of the following characters: body elongated, slender, and not pigmented in preserved specimens; tail (postabdominal region) distinctly shorter than abdomen; origin of the dorsal fin distinctly anterior to origin of the anal fin (LDF type); predorsal-fin length 63.1-63.5% of SL; preanal-fin length 71.2-73.0% of SL; body depth at the origin of the anal-fin 5.9-6.6% of SL; head length 14.4-15.6% of SL; head depth 7.8-8.1% of SL; eye diameter 3.3-3.6% of SL and 23.1-26.1% of the head length; pectoral radial plate length 5.6-5.8% of SL; maximum width of the pectoral radial plate 3.2-3.3% of SL and 56.9-57.1% of pectoral radial plate length; depth of the hypural late 66.7% of the urostyle length; 16 dorsal-fin rays; 13 anal-fin rays, first anal-fin ray positioned below the 5-6th dorsal-fin ray; six procurrent rays; swim-bladder not pigmented; continuous row of small, conical teeth on premaxillary but zero teeth on the dentary of the holotype or five teeth (right) plus two isolated teeth (left) in the dentary of the paratype. ....
Etymology: The specific name ‘nana’ (from the Latin ‘nanus’ – dwarf) refers to the small size of this species.
Harald Ahnelt, Oliver Macek and Vanessa Robitzch. 2024. Schindleria nana, A New extremely progenetic gobiid fish Species (Teleostei: Gobiiformes: Gobiidae) from Lizard Island, Great Barrier Reef, Australia. J. of Vertebrate Biology. 73: 23112.1-17. DOI: 10.25225/jvb.23112
==========================
Schindleria nana
Ahnelt, Macek & Robitzch, 2024
DOI: 10.25225/jvb.23112
Abstract
Here, we describe a new species of Schindleria, Schindleria nana, from Lizard Island, Great Barrier Reef, Australia. The new species belongs to the long dorsal-fin type (LDF) of Schindleria and is the first very small (‘dwarf’) LDF species (< 13 mm TL) to be described. It is characterized by an elongate and narrow body; a dorsal fin longer than the anal fin (predorsal-fin length 63.3% of SL: preanal-fin length 72.1% of SL); a long, relatively narrow head (head width 46.2% of head length) with a straight profile; small and round eyes (24.9% of head length); a large postorbital distance (52% of head length); a narrow, slender pectoral radial plate (width at origin 46.4%, maximum width 57.0% of pectoral radial plate length); 16 dorsal-fin rays; 11-12 anal-fin rays; first anal-fin ray ventral to the sixth dorsal-fin ray; six procurrent rays gradually increasing in length, last ray elongated, twice the length of the penultimate ray; premaxilla with tiny, conical, densely set teeth; dentary with zero teeth in the holotype and with two teeth on the left dentary and five teeth on the right dentary in the adult paratype; females with few (approx. 4-7) but very large eggs (3.4-3.9% of SL); urogenital papilla inconspicuous, de facto just an urogenital opening; swim bladder not pigmented; black eyes; no other external pigmentation on the body.
KEYWORDS: Coral reefs, Indo-Pacific, Miniaturization, new species, progenesis, taxonomy
Holotype of Schindleria nana, AMS.I.23115-004, female, 9.0 mm SL; Australia, Queensland, Lizard Island.
an – anus, ug – urogenital opening. Black asterisk – position of first anal-fin ray, white asterisk – position of first dorsal-fin ray. Scale bar: 1 mm.
Schindleria nana
Diagnosis: The new species S. nana stands out from its congeners because it is the first small-sized species (< 10 mm SL) in the LDF species group and the first LDF Schindleria with only a few (4-7) and very large eggs (3.1-3.6% of SL) (Figs. 3, 4A). It differs from its congeners in the combination of the following characters: body elongated, slender, and not pigmented in preserved specimens; tail (postabdominal region) distinctly shorter than abdomen; origin of the dorsal fin distinctly anterior to origin of the anal fin (LDF type); predorsal-fin length 63.1-63.5% of SL; preanal-fin length 71.2-73.0% of SL; body depth at the origin of the anal-fin 5.9-6.6% of SL; head length 14.4-15.6% of SL; head depth 7.8-8.1% of SL; eye diameter 3.3-3.6% of SL and 23.1-26.1% of the head length; pectoral radial plate length 5.6-5.8% of SL; maximum width of the pectoral radial plate 3.2-3.3% of SL and 56.9-57.1% of pectoral radial plate length; depth of the hypural late 66.7% of the urostyle length; 16 dorsal-fin rays; 13 anal-fin rays, first anal-fin ray positioned below the 5-6th dorsal-fin ray; six procurrent rays; swim-bladder not pigmented; continuous row of small, conical teeth on premaxillary but zero teeth on the dentary of the holotype or five teeth (right) plus two isolated teeth (left) in the dentary of the paratype. ....
Etymology: The specific name ‘nana’ (from the Latin ‘nanus’ – dwarf) refers to the small size of this species.
Harald Ahnelt, Oliver Macek and Vanessa Robitzch. 2024. Schindleria nana, A New extremely progenetic gobiid fish Species (Teleostei: Gobiiformes: Gobiidae) from Lizard Island, Great Barrier Reef, Australia. J. of Vertebrate Biology. 73: 23112.1-17. DOI: 10.25225/jvb.23112
==========================
Increasing the species diversity of the monotypic genus Pariolius Cope 1872 (Siluriformes: Heptapteridae) after more than 150 yearsPISCESENDEMICFRESHWATERMORPHOLOGYSPECIES DELIMITATIONSTAXONOMYAbstractPariolius is a heptapterid genus represented by P. armillatus that is distributed along the upper Amazon River basin. A taxonomic integrative revision of Pariolius from Colombian Rivers revealed two new species. Several approaches as morphological, morphometric, meristic, osteology and molecular data were used to distinguish between Pariolius species. The two new species are distinguished from congeners by the caudal-fin shape and numbers of rays, colorations patterns and several morphometric characters. The two new species of Pariolius are restricted to tributaries of the Upper Orinoco and Upper Negro rivers in Colombia.
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Chiloglanis carnatus • Hidden in the Riffles: A New Suckermouth Catfish (Siluriformes: Mochokidae: Chiloglanis) from the middle Zambezi River system, Zimbabwe
Chiloglanis carnatus Mutizwa, Bragança & Chakona,
in Mutizwa, Kadye, Bragança, Bere et Chakona, 2024.
DOI: 10.3897/zookeys.1197.114679
Abstract
The recent surge in the discovery of hidden diversity within rheophilic taxa, particularly in West and East Africa, prompted a closer examination of the extent to which the current taxonomy may obscure the diversity of riffle-dwelling suckermouth catfishes in the genus Chiloglanis in southern Africa. Currently, the region comprises eight valid species within this genus. Seven of them have relatively narrow geographic distribution ranges except for C. neumanni, which is considered to be widely distributed, occurring from the Buzi River system in the south, and its northern limit being the eastward draining river systems in Tanzania. Recent surveys of the middle Zambezi River system revealed Chiloglanis specimens that were distinguishable from the known species of the genus from southern Africa. Integration of molecular and morphological data indicated that these specimens from the Mukwadzi River represent a new species to science, herein described as Chiloglanis carnatus Mutizwa, Bragança & Chakona, sp. nov. This species is readily distinguished from its southern African congeners by the possession of a distinctive extended dermal tissue covering the base of the dorsal fin and the possession of ten mandibular teeth (vs 8, 12, or 14 in the other taxa). Results from this study add to the growing evidence of a high level of undocumented diversity within riffle-dwelling taxa in southern Africa.
Key words: Diversity, freshwater, integrative taxonomy, rheophilic taxa, southern Africa
Holotype of Chiloglanis carnatus sp. nov., SAIAB 236631 male (A–E) and
female paratype specimen SAIAB 211346 (F–K).
Scale bars: 1 cm.
Chiloglanis carnatus Mutizwa, Bragança & Chakona, sp. nov.
Diagnosis: Chiloglanis carnatus sp. nov. is readily distinguished from its congeners in southern Africa (i.e. C. anoterus, C. bifurcus, C. emarginatus, C. fasciatus, C. paratus, C. pretoriae and C. swierstrai) by the presence of a dorsal fin that has a basal portion covered by a fleshy skin, a character which is absent in the other species. Chiloglanis carnatus possesses ten closely packed mandibular teeth, that further distinguishes it from C. fasciatus that has eight closely packed mandibular teeth; C. bifurcus and C. emarginatus that have ...
Etymology: The specific epithet carnatus means fleshy, referring to the dermal tissue covering the base of the dorsal fin of some of the larger specimens of this species and the general robust body structure of this species compared to its regional congeners.
Tadiwa I. Mutizwa, Wilbert T. Kadye, Pedro H. N. Bragança, Taurai Bere and Albert Chakona. 2024. Hidden in the Riffles: A New Suckermouth Catfish (Mochokidae, Chiloglanis) from the middle Zambezi River system, Zimbabwe. ZooKeys. 1197: 57-91. DOI: 10.3897/zookeys.1197.114679
Chiloglanis carnatus Mutizwa, Bragança & Chakona,
in Mutizwa, Kadye, Bragança, Bere et Chakona, 2024.
DOI: 10.3897/zookeys.1197.114679
Abstract
The recent surge in the discovery of hidden diversity within rheophilic taxa, particularly in West and East Africa, prompted a closer examination of the extent to which the current taxonomy may obscure the diversity of riffle-dwelling suckermouth catfishes in the genus Chiloglanis in southern Africa. Currently, the region comprises eight valid species within this genus. Seven of them have relatively narrow geographic distribution ranges except for C. neumanni, which is considered to be widely distributed, occurring from the Buzi River system in the south, and its northern limit being the eastward draining river systems in Tanzania. Recent surveys of the middle Zambezi River system revealed Chiloglanis specimens that were distinguishable from the known species of the genus from southern Africa. Integration of molecular and morphological data indicated that these specimens from the Mukwadzi River represent a new species to science, herein described as Chiloglanis carnatus Mutizwa, Bragança & Chakona, sp. nov. This species is readily distinguished from its southern African congeners by the possession of a distinctive extended dermal tissue covering the base of the dorsal fin and the possession of ten mandibular teeth (vs 8, 12, or 14 in the other taxa). Results from this study add to the growing evidence of a high level of undocumented diversity within riffle-dwelling taxa in southern Africa.
Key words: Diversity, freshwater, integrative taxonomy, rheophilic taxa, southern Africa
Holotype of Chiloglanis carnatus sp. nov., SAIAB 236631 male (A–E) and
female paratype specimen SAIAB 211346 (F–K).
Scale bars: 1 cm.
Chiloglanis carnatus Mutizwa, Bragança & Chakona, sp. nov.
Diagnosis: Chiloglanis carnatus sp. nov. is readily distinguished from its congeners in southern Africa (i.e. C. anoterus, C. bifurcus, C. emarginatus, C. fasciatus, C. paratus, C. pretoriae and C. swierstrai) by the presence of a dorsal fin that has a basal portion covered by a fleshy skin, a character which is absent in the other species. Chiloglanis carnatus possesses ten closely packed mandibular teeth, that further distinguishes it from C. fasciatus that has eight closely packed mandibular teeth; C. bifurcus and C. emarginatus that have ...
Etymology: The specific epithet carnatus means fleshy, referring to the dermal tissue covering the base of the dorsal fin of some of the larger specimens of this species and the general robust body structure of this species compared to its regional congeners.
Tadiwa I. Mutizwa, Wilbert T. Kadye, Pedro H. N. Bragança, Taurai Bere and Albert Chakona. 2024. Hidden in the Riffles: A New Suckermouth Catfish (Mochokidae, Chiloglanis) from the middle Zambezi River system, Zimbabwe. ZooKeys. 1197: 57-91. DOI: 10.3897/zookeys.1197.114679
A review of the Heteroclinus heptaeolus complex (Pisces: Blennioidei: Clinidae), with three new species and discussion of use of proportions in taxonomic studiesPISCESFISHBLENNIIFORMESICHTHYOLOGYTAXONOMYPROPORTIONSWEEDFISHAbstractThe present paper reviews the Heteroclinus heptaeolus complex known only from temperate regions of Australia. Five species are recognised, with three of the species described as new, H. colemani, a deep bodied species often found around red algae, H. whitleyi, with two disjunct populations and a species very close to and sympatric with H. heptaeolus (Ogilby), H. longicauda, a slender species, lacking an orbital tentacle. In addition, Heteroclinus wilsoni (Lucas) is recognised as a distinct species and a neotype is selected. The species are separated on the bases of live coloration, pectoral ray, dorsal spine and anal ray counts, gill raker counts, development of orbital tentacle, first dorsal fin height and body depth. Analysis of measurements indicates that proportions commonly used to separate species are often unreliable, because of high variation and significant changes with size. Proportions were found to not be good estimates of the slope of the regression line of various characters with the standard length.
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Serrasalmus magallanesi • A New Species of Piranha (Characiformes: Serrasalmidae: Serrasalmus) from the Upper Madeira River System, Amazon Basin, Bolivia
Serrasalmus magallanesi
Gallo-Cardozo, Maldonado, Careaga & Carvajal-Vallejos, 2024
DOI: 10.1134/S0032945224700036
facebook.com/FlavioGalloCardozo
Abstract
A new species of piranha, in the genus Serrasalmus (Characiformes, Serrasalmidae), is described from tributaries of the upper Madeira River drainage (Bolivian Amazon Basin). This new species exhibits a similar caudal-fin color like that observed in S. hollandi, and review of the literature suggested that former studies have misidentified these two species. The new species can be diagnosed morphologically from other congeners, but genetic variation of the COI sequence data showed little difference (~1%) from similar, morphologically recognized species. Since Serrasalmus species are widespread and morphologically difficult to identify, a key for identifying Bolivian species of this genus is presented.
Keywords: COI, morphology, osteology, taxonomy
Serrasalmus magallanesi, New Species
Etymology. Serrasalmus magallanesi sp. nov. is named in honor and memoriam of Frank Magallanes, in recognition of his permanent collaboration with ichthyologists and Serrasalmus fans, mainly through his website OPEFE (https://www.opefe.com). Magallanes passed away in May 2022.
F. Gallo-Cardozo, M. Maldonado, M. Careaga and F. M. Carvajal-Vallejos. 2024. A New Species of Piranha (Serrasalmus, Serrasalmidae) from the Upper Madeira River System, Amazon Basin, Bolivia. Journal of Ichthyology. DOI: 10.1134/S0032945224700036
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Serrasalmus magallanesi
Gallo-Cardozo, Maldonado, Careaga & Carvajal-Vallejos, 2024
DOI: 10.1134/S0032945224700036
facebook.com/FlavioGalloCardozo
Abstract
A new species of piranha, in the genus Serrasalmus (Characiformes, Serrasalmidae), is described from tributaries of the upper Madeira River drainage (Bolivian Amazon Basin). This new species exhibits a similar caudal-fin color like that observed in S. hollandi, and review of the literature suggested that former studies have misidentified these two species. The new species can be diagnosed morphologically from other congeners, but genetic variation of the COI sequence data showed little difference (~1%) from similar, morphologically recognized species. Since Serrasalmus species are widespread and morphologically difficult to identify, a key for identifying Bolivian species of this genus is presented.
Keywords: COI, morphology, osteology, taxonomy
Serrasalmus magallanesi, New Species
Etymology. Serrasalmus magallanesi sp. nov. is named in honor and memoriam of Frank Magallanes, in recognition of his permanent collaboration with ichthyologists and Serrasalmus fans, mainly through his website OPEFE (https://www.opefe.com). Magallanes passed away in May 2022.
F. Gallo-Cardozo, M. Maldonado, M. Careaga and F. M. Carvajal-Vallejos. 2024. A New Species of Piranha (Serrasalmus, Serrasalmidae) from the Upper Madeira River System, Amazon Basin, Bolivia. Journal of Ichthyology. DOI: 10.1134/S0032945224700036
facebook.com/FlavioGalloCardozo/posts/7723189084379968
==========================
Monotocheirodon duda • A New characid Species with remarkable sexual dimorphism (Characiformes: Characidae: Stevardiinae) from the upper Guayabero River, Orinoco Basin, Colombia
Monotocheirodon duda
Carvalho, Thomaz, Urbano-Bonilla & Prada-Pedreros, 2024
DOI: 10.1111/jfb.15738
Abstract
A new species of characid with remarkable sexual characteristics is described from the upper Guayabero River drainage from the Orinoco basin in Colombia. The new species is included in the genus Monotocheirodon by sharing most of the previously proposed diagnostic features of this genus. It differs from all Stevardiinae by the combination, in adult males, of an enlarged urogenital papilla in contact with the first anal-fin unbranched ray and a highly modified anal fin with enlarged and distally elongated first and second branched anal-fin rays, forming a gonopodium-like structure. In addition, it differs from congeners by the presence of an adipose fin, an incomplete lateral line, an ascending process of the premaxilla dorsally oriented, and a long snout. The new species was discovered from a poorly sampled region in Colombia and is an unexpected new record given its disjunct geographic distribution from other species of the genus. Monotocheirodon species were previously known from piedmont drainages in Bolivia and Peru. The conservation status of the new species is herein categorized following IUCN criteria.
Keywords: endemism, insemination, Monotocheirodon, sexual characters, South America, species diversity
Lateral view of live specimens of Monotocheirodon duda showing live colouration. Above a male and below a female specimen. Specimens not cataloged.
Monotocheirodon duda, new species
Diagnosis: The new species differs from all Stevardiinae species by the combined presence in adult males of an enlarged urogenital papilla (length about one-third to half of the first unbranched ray), which is in contact with the first anal-fin unbranched ray and a highly modified anal fin, with enlarged (anteroposteriorly) and distally elongated first and second branched anal-fin rays, forming a gonopodium-like structure (Figure 2). The new species differs from all other species of Monotocheirodon by the presence of an adipose fin (Figure 1, vs. absent); lateral line incomplete, pored scales not reaching the caudal fin (vs. lateral line complete); ascending process of the premaxilla dorsally directed (Figure 3, vs. strongly bent posteroventrally); and a longer snout that occupies about a fourth of the head length (HL), between 23.1% and 30.0% of HL (vs. short snout, <20% of the HL).
Etymology: Monotocheiron duda is named after the river where the new species was captured, mostly tributaries to the Duda River or captured in the Duda River itself (type locality). In Spanish, the epithet specific “duda” means doubt, which also refers to its presumed placement into the genus Monotocheirodon, an assumption that needs further evaluation.
Tiago P. Carvalho, Andréa Tonolli Thomaz, Alexander Urbano-Bonilla and Saúl Prada-Pedreros. 2024. A New characid Species with remarkable sexual dimorphism (Characiformes: Characidae: Stevardiinae) from the upper Guayabero River, Orinoco basin, Colombia. Journal of Fish Biology. DOI: 10.1111/jfb.15738
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Monotocheirodon duda
Carvalho, Thomaz, Urbano-Bonilla & Prada-Pedreros, 2024
DOI: 10.1111/jfb.15738
Abstract
A new species of characid with remarkable sexual characteristics is described from the upper Guayabero River drainage from the Orinoco basin in Colombia. The new species is included in the genus Monotocheirodon by sharing most of the previously proposed diagnostic features of this genus. It differs from all Stevardiinae by the combination, in adult males, of an enlarged urogenital papilla in contact with the first anal-fin unbranched ray and a highly modified anal fin with enlarged and distally elongated first and second branched anal-fin rays, forming a gonopodium-like structure. In addition, it differs from congeners by the presence of an adipose fin, an incomplete lateral line, an ascending process of the premaxilla dorsally oriented, and a long snout. The new species was discovered from a poorly sampled region in Colombia and is an unexpected new record given its disjunct geographic distribution from other species of the genus. Monotocheirodon species were previously known from piedmont drainages in Bolivia and Peru. The conservation status of the new species is herein categorized following IUCN criteria.
Keywords: endemism, insemination, Monotocheirodon, sexual characters, South America, species diversity
Lateral view of live specimens of Monotocheirodon duda showing live colouration. Above a male and below a female specimen. Specimens not cataloged.
Monotocheirodon duda, new species
Diagnosis: The new species differs from all Stevardiinae species by the combined presence in adult males of an enlarged urogenital papilla (length about one-third to half of the first unbranched ray), which is in contact with the first anal-fin unbranched ray and a highly modified anal fin, with enlarged (anteroposteriorly) and distally elongated first and second branched anal-fin rays, forming a gonopodium-like structure (Figure 2). The new species differs from all other species of Monotocheirodon by the presence of an adipose fin (Figure 1, vs. absent); lateral line incomplete, pored scales not reaching the caudal fin (vs. lateral line complete); ascending process of the premaxilla dorsally directed (Figure 3, vs. strongly bent posteroventrally); and a longer snout that occupies about a fourth of the head length (HL), between 23.1% and 30.0% of HL (vs. short snout, <20% of the HL).
Etymology: Monotocheiron duda is named after the river where the new species was captured, mostly tributaries to the Duda River or captured in the Duda River itself (type locality). In Spanish, the epithet specific “duda” means doubt, which also refers to its presumed placement into the genus Monotocheirodon, an assumption that needs further evaluation.
Tiago P. Carvalho, Andréa Tonolli Thomaz, Alexander Urbano-Bonilla and Saúl Prada-Pedreros. 2024. A New characid Species with remarkable sexual dimorphism (Characiformes: Characidae: Stevardiinae) from the upper Guayabero River, Orinoco basin, Colombia. Journal of Fish Biology. DOI: 10.1111/jfb.15738
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Descriptions of two new species of the botiid genus Leptobotia Bleeker, 1870 (Teleostei: Cypriniformes) from South China
Dong-Ming Guo, Liang Cao, E. Zhang
First published: 06 March 2023
https://doi.org/10.1111/jfb.15347
Citations: 1
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SHAREAbstractENTHIS LINK GOES TO A ENGLISH SECTIONZHTHIS LINK GOES TO A ENGLISH SECTIONTwo new species of Leptobotia are here described as L. rotundilobus from the Xin'an-Jiang of the upper Qiantang-Jiang basin in both Anhui and Zhejiang Provinces and the Cao'e-Jiang in Zhejiang Province, and L. paucipinna from the Qing-Jiang of the middle Chang-Jiang basin in Hubei Province, South China. Both have a plain brown body as found in L. bellacauda Bohlen & Šlechtová, 2016, L. microphthalma Fu & Ye, 1983, L. posterodorsalis Chen & Lan, 1992 and L. tientainensis (Wu, 1930). The two new species are distinct from these species in vertebral counts, further from L. posterodorsalis in vent placement and further from the other three species in pectoral-fin length. Both differ in caudal-fin coloration and shape, and dorsal-fin location and coloration, and also in internal morphology. Their validity is confirmed by their own monophyly recovered in a phylogenetic analysis based on the mitochondrial cyt b and COI genes.
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Lepadichthys geminus, L. heemstraorum & L. polyastrous • Review of the Lepadichthys lineatus complex (Gobiesocidae: Diademichthyinae) with Descriptions of Three New Species
Lepadichthys geminus
Fujiwara & Motomura, 2022
DOI: 10.1111/jfb.14919
twitter.com/kadai_museum
Abstract
The Lepadichthys lineatus complex (Gobiesocidae: Diademichthyinae) is defined by three unique characters within Lepadichthys: (a) upper-jaw lip fused with snout skin, usually lacking a distinct groove between the dorsal lip margin and snout (if present, very weak, restricted to posterior portion of jaw); (b) snout tip well extended, distinctly beyond lower-jaw tip; and (c) inner surface of both lips with oral papillae. A taxonomic review of the complex recognized four valid species: Lepadichthys geminus sp. nov. (southern Japan and Indonesia), Lepadichthys heemstraorum sp. nov. (southwestern Indian Ocean), Lepadichthys polyastrous sp. nov. (southwestern Indian Ocean) and L. lineatus Briggs, 1966 (Red Sea, Arabian Sea, Seychelles and Sri Lanka). L. geminus and L. lineatus are distinct from L. heemstraorum and L. polyastrous in having a circular (vs. elliptical) disc and more posteriorly located anus [L. geminus and L. lineatus with disc length and width 15.0–18.7 (mean 16.9) and 12.9–16.5 (14.6) % LS, respectively, and length to width ratio 1.03–1.25 cf. L. heemstraorum and L. polyastrous, 17.0–21.5 (18.9) and 11.6–15.2 (13.0) % LS, respectively, and 1.26–1.61; pre-anus length and disc to anus length 65.1–73.6 (68.7) and 25.7–31.6 (28.6) % LS, respectively vs. 60.2–68.3 (65.3) and 21.6–28.9 (25.5) % LS, respectively]. Body depth (as % of LS) is also useful to distinguish L. geminus and L. polyastrous from L. heemstraorum and L. lineatus [viz., 12.7–16.1 (14.4) in L. geminus and 10.8–14.9 (13.1) in L. polyastrous vs. 15.0–17.1 (15.9) in L. heemstraorum and 14.6–18.9 (16.8) in L. lineatus]. L. geminus differs distinctly from other species in the complex as follows: snout tip directed upward, usually on same horizontal level with lower margin of eye lens (lateral view) (vs. directed somewhat downward, horizontal level usually between lower margins of eye and eye lens in L. heemstraorum and L. lineatus, lower margin of eye in L. polyastrous); and lower abdomen with two yellow stripes (vs. a single stripe along ventral midline in L. polyastrous and L. lineatus, unknown in L. heemstraorum). L. polyastrous has unique patterns of yellow dots on the dorsal and ventral body surfaces, forming c. six to eight and three to five longitudinal rows, respectively [vs. usually forming c. three to five longitudinal rows and a single broken line, respectively, in L. geminus and L. lineatus; yellow dots usually absent in L. heemstraorum]. A poorly known species, Lepadichthys caritus Briggs, 1969, is regarded as a junior synonym of L. lineatus.
Fresh holotype of Lepadichthys geminus sp. nov. (KAUM–I. 145214, 22.3 mm LS, Okinoerabu Island, Amami Islands, Japan).
The Lepadichthys lineatus complex
Lepadichthys geminus sp. nov.
New English name: Pacific Doubleline Clingfish;
standard Japanese name: Tasuji-umishida-ubauo
Etymology. The specific name “geminus” is derived from Latin, meaning “twin” or “double,” in reference to the two yellow stripes under the abdomen and the close morphological similarity of the new species to L. lineatus, with which it had previously been identified.
Lepadichthys heemstraorum sp. nov.
New English name: Heemstra's Clingfish
Etymology. The specific name “heemstraorum” is in honour of an esteemed ichthyologist, the late Dr Phil Heemstra, who with his wife Elaine Heemstra collected type specimens of L. heemstraorum and L. polyastrous.
Lepadichthys polyastrous sp. nov.
New English name: Starry Clingfish
Etymology. The specific name “polyastrous,” a combination of the New Greek “polys” and “astrous,” means “many stars,” in reference to the many characteristic yellow dots on the body.
Lepadichthys lineatus Briggs 1966
English name: Doubleline Clingfish
Kyoji Fujiwara and Hiroyuki Motomura. 2022. Review of the Lepadichthys lineatus complex (Gobiesocidae: Diademichthyinae) with Descriptions of Three New Species. Journal of Fish Biology. 100(1); 62-81. DOI: 10.1111/jfb.14919
twitter.com/kadai_museum/status/1451554505875550215
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Lepadichthys geminus
Fujiwara & Motomura, 2022
DOI: 10.1111/jfb.14919
twitter.com/kadai_museum
Abstract
The Lepadichthys lineatus complex (Gobiesocidae: Diademichthyinae) is defined by three unique characters within Lepadichthys: (a) upper-jaw lip fused with snout skin, usually lacking a distinct groove between the dorsal lip margin and snout (if present, very weak, restricted to posterior portion of jaw); (b) snout tip well extended, distinctly beyond lower-jaw tip; and (c) inner surface of both lips with oral papillae. A taxonomic review of the complex recognized four valid species: Lepadichthys geminus sp. nov. (southern Japan and Indonesia), Lepadichthys heemstraorum sp. nov. (southwestern Indian Ocean), Lepadichthys polyastrous sp. nov. (southwestern Indian Ocean) and L. lineatus Briggs, 1966 (Red Sea, Arabian Sea, Seychelles and Sri Lanka). L. geminus and L. lineatus are distinct from L. heemstraorum and L. polyastrous in having a circular (vs. elliptical) disc and more posteriorly located anus [L. geminus and L. lineatus with disc length and width 15.0–18.7 (mean 16.9) and 12.9–16.5 (14.6) % LS, respectively, and length to width ratio 1.03–1.25 cf. L. heemstraorum and L. polyastrous, 17.0–21.5 (18.9) and 11.6–15.2 (13.0) % LS, respectively, and 1.26–1.61; pre-anus length and disc to anus length 65.1–73.6 (68.7) and 25.7–31.6 (28.6) % LS, respectively vs. 60.2–68.3 (65.3) and 21.6–28.9 (25.5) % LS, respectively]. Body depth (as % of LS) is also useful to distinguish L. geminus and L. polyastrous from L. heemstraorum and L. lineatus [viz., 12.7–16.1 (14.4) in L. geminus and 10.8–14.9 (13.1) in L. polyastrous vs. 15.0–17.1 (15.9) in L. heemstraorum and 14.6–18.9 (16.8) in L. lineatus]. L. geminus differs distinctly from other species in the complex as follows: snout tip directed upward, usually on same horizontal level with lower margin of eye lens (lateral view) (vs. directed somewhat downward, horizontal level usually between lower margins of eye and eye lens in L. heemstraorum and L. lineatus, lower margin of eye in L. polyastrous); and lower abdomen with two yellow stripes (vs. a single stripe along ventral midline in L. polyastrous and L. lineatus, unknown in L. heemstraorum). L. polyastrous has unique patterns of yellow dots on the dorsal and ventral body surfaces, forming c. six to eight and three to five longitudinal rows, respectively [vs. usually forming c. three to five longitudinal rows and a single broken line, respectively, in L. geminus and L. lineatus; yellow dots usually absent in L. heemstraorum]. A poorly known species, Lepadichthys caritus Briggs, 1969, is regarded as a junior synonym of L. lineatus.
Fresh holotype of Lepadichthys geminus sp. nov. (KAUM–I. 145214, 22.3 mm LS, Okinoerabu Island, Amami Islands, Japan).
The Lepadichthys lineatus complex
Lepadichthys geminus sp. nov.
New English name: Pacific Doubleline Clingfish;
standard Japanese name: Tasuji-umishida-ubauo
Etymology. The specific name “geminus” is derived from Latin, meaning “twin” or “double,” in reference to the two yellow stripes under the abdomen and the close morphological similarity of the new species to L. lineatus, with which it had previously been identified.
Lepadichthys heemstraorum sp. nov.
New English name: Heemstra's Clingfish
Etymology. The specific name “heemstraorum” is in honour of an esteemed ichthyologist, the late Dr Phil Heemstra, who with his wife Elaine Heemstra collected type specimens of L. heemstraorum and L. polyastrous.
Lepadichthys polyastrous sp. nov.
New English name: Starry Clingfish
Etymology. The specific name “polyastrous,” a combination of the New Greek “polys” and “astrous,” means “many stars,” in reference to the many characteristic yellow dots on the body.
Lepadichthys lineatus Briggs 1966
English name: Doubleline Clingfish
Kyoji Fujiwara and Hiroyuki Motomura. 2022. Review of the Lepadichthys lineatus complex (Gobiesocidae: Diademichthyinae) with Descriptions of Three New Species. Journal of Fish Biology. 100(1); 62-81. DOI: 10.1111/jfb.14919
twitter.com/kadai_museum/status/1451554505875550215
==========================
Bashimyzon cheni, a new genus and species of sucker loach (Teleostei, Gastromyzontidae) from South China
Xiong Gong, E ZhangAbstractBashimyzon, new genus, is here established for Erromyzon damingshanensis, and a new species of the genus is described from the You-Jiang of the Pearl River (=Zhu-Jiang in mandarin Chinese) basin in Guangxi Province, South China. This new genus has a small gill opening above the pectoral-fin base and short pectoral fins extending backwards short of pelvic-fin insertions, both characters combined to separate it from all currently-recognized gastromyzontid genera except Erromyzon and Protomyzon, but differs from the two genera in having a larger gap between the posterior edge of eye and the vertical through the pectoral-fin insertion and very small fleshy lobes posterior to the maxillary-barbel bases. It is further distinct from its most similar genus Erromyzon in having a relatively larger gill opening, fewer branched pectoral-fin rays folded against body, and more posteriorly placed pectoral fins with a shorter fin base. Bashimyzon cheni, new species, and B. damingshanensis, the single congeneric species, differ in number of lateral-line pored scales, body coloration, and cephalic contour, and also in substantial genetic divergence.
LINK doi.org/10.3897/zse.100.116535
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Xiong Gong, E ZhangAbstractBashimyzon, new genus, is here established for Erromyzon damingshanensis, and a new species of the genus is described from the You-Jiang of the Pearl River (=Zhu-Jiang in mandarin Chinese) basin in Guangxi Province, South China. This new genus has a small gill opening above the pectoral-fin base and short pectoral fins extending backwards short of pelvic-fin insertions, both characters combined to separate it from all currently-recognized gastromyzontid genera except Erromyzon and Protomyzon, but differs from the two genera in having a larger gap between the posterior edge of eye and the vertical through the pectoral-fin insertion and very small fleshy lobes posterior to the maxillary-barbel bases. It is further distinct from its most similar genus Erromyzon in having a relatively larger gill opening, fewer branched pectoral-fin rays folded against body, and more posteriorly placed pectoral fins with a shorter fin base. Bashimyzon cheni, new species, and B. damingshanensis, the single congeneric species, differ in number of lateral-line pored scales, body coloration, and cephalic contour, and also in substantial genetic divergence.
LINK doi.org/10.3897/zse.100.116535
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Curculionichthys monolechis • A New Species of Curculionichthys (Siluriformes: Loricariidae) from the Saramacca and Marowijne River Basins, Suriname and French Guiana
Curculionichthys monolechis
de Morais, Gamarra & Reis, 2024
DOI: 10.1643/i2023051
twitter.com/IchsAndHerps
Abstract
A new species of Curculionichthys is described from the Saramacca and Marowijne (=Maroni) River basins in Suriname and French Guiana, eastern Guiana Shield. The new species possesses five of the seven diagnostic characteristics of the genus with the most remarkable morphological trait that distinguishes it from congeners being the presence of a single rostral plate. A genetic comparison with C. karipuna, the geographically closest species, showed a minimal distance of 5% in gene coI between individuals of the two species. The geographic distribution further extends the distribution of the genus across the Guiana Shield and represents the first species of the genus described from outside Brazil.
Curculionichthys monolechis, live coloration. Saut Tampock, Tampock River basin, Maroni drainage, French Guiana. Specimen not preserved.
Image from Le Bail et al. (2000).
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Curculionichthys monolechis, new species
Etymology.— Curculionichthys monolechis is from the Greek (monos), one, single, and (lekos), plate, in reference to the single rostral plate. A noun in apposition.
Andressa de Morais, Suelen P. Gamarra, Roberto E. Reis. 2024. A New Species of Curculionichthys (Siluriformes: Loricariidae) from the Saramacca and Marowijne River Basins, Suriname and French Guiana. Ichthyology & Herpetology. 112(1):60-68. DOI: 10.1643/i2023051
twitter.com/IchsAndHerps/status/1765758157169586419
Uma nova espécie de Curculionichthys é descrita das bacias dos rios Saramacca e Marowijne (=Maroni), no leste do Escudo das Guianas, no Suriname e Guiana Francesa. A nova espécie possui cinco das sete características diagnosticas do gênero, sendo a característica morfológica mais marcante que a distingue das demais congêneres a presença de placa rostral única. A comparação genética com C. karipuna, a espécie geograficamente mais próxima, mostrou uma distância mínima de 5% entre os indivíduos das duas espécies. A distribuição geográfica da espécie estende a ocorrência do gênero no Escudo das Guianas e representa a primeira espécie descrita de fora do Brasil.
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Curculionichthys monolechis
de Morais, Gamarra & Reis, 2024
DOI: 10.1643/i2023051
twitter.com/IchsAndHerps
Abstract
A new species of Curculionichthys is described from the Saramacca and Marowijne (=Maroni) River basins in Suriname and French Guiana, eastern Guiana Shield. The new species possesses five of the seven diagnostic characteristics of the genus with the most remarkable morphological trait that distinguishes it from congeners being the presence of a single rostral plate. A genetic comparison with C. karipuna, the geographically closest species, showed a minimal distance of 5% in gene coI between individuals of the two species. The geographic distribution further extends the distribution of the genus across the Guiana Shield and represents the first species of the genus described from outside Brazil.
Curculionichthys monolechis, live coloration. Saut Tampock, Tampock River basin, Maroni drainage, French Guiana. Specimen not preserved.
Image from Le Bail et al. (2000).
twitter.com/IchsAndHerps
Curculionichthys monolechis, new species
Etymology.— Curculionichthys monolechis is from the Greek (monos), one, single, and (lekos), plate, in reference to the single rostral plate. A noun in apposition.
Andressa de Morais, Suelen P. Gamarra, Roberto E. Reis. 2024. A New Species of Curculionichthys (Siluriformes: Loricariidae) from the Saramacca and Marowijne River Basins, Suriname and French Guiana. Ichthyology & Herpetology. 112(1):60-68. DOI: 10.1643/i2023051
twitter.com/IchsAndHerps/status/1765758157169586419
Uma nova espécie de Curculionichthys é descrita das bacias dos rios Saramacca e Marowijne (=Maroni), no leste do Escudo das Guianas, no Suriname e Guiana Francesa. A nova espécie possui cinco das sete características diagnosticas do gênero, sendo a característica morfológica mais marcante que a distingue das demais congêneres a presença de placa rostral única. A comparação genética com C. karipuna, a espécie geograficamente mais próxima, mostrou uma distância mínima de 5% entre os indivíduos das duas espécies. A distribuição geográfica da espécie estende a ocorrência do gênero no Escudo das Guianas e representa a primeira espécie descrita de fora do Brasil.
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Cosmoselachus mehlingi • A New operculate symmoriiform chondrichthyan (Symmoriiformes: Falcatidae) from the Late Mississippian Fayetteville Shale, Arkansashale (Arkansas, United States)
Cosmoselachus mehlingi
Bronson, Pradel, Denton & Maisey, 2024
sciencepress.mnhn.fr/en/periodiques/geodiversitas/46/4
twitter.com/AMNH
twitter.com/Kimi_Chap
We describe a new genus of symmoriiform chondrichthyan from the Late Mississippian Fayetteville Shale of Arkansas, United States, and include this fossil in a phylogenetic analysis of chondrichthyans. This taxon possesses elongate cartilaginous rays extending from the gill arches, forming an operculate structure that covers at least two of the branchial arches farther posteriorly. Although presence of a ‘hyoid operculum’ has been postulated in at least two unrelated Paleozoic sharks (e.g., Triodus, Tristychius), subsequent investigations failed to corroborate those claims. The new fossil therefore provides the first evidence of an endoskeletal operculum formed by elongate, fused pharyngeal arch rays in a chondrichthyan.
KEYWORDS: Chondrichthyes, Symmoriiformes, operculum, CT scanning, phylogeny, new genus, new species
An artist’s reconstruction of the new shark-like species Cosmoselachus mehlingi.
amnh.org
Class CHONDRICHTHYES Huxley, 1880
Order SYMMORIIFORMES Maisey, 2007
Family Falcatidae Zangerl, 1990
Genus Cosmoselachus n. gen.
Cosmoselachus mehlingi
Etymology: Cosmoselachus mehlingi n. gen., n. sp. is named in honor of American Museum of Natural History Senior Museum Specialist Carl Mehling, nickname “Cosm”, therefore “Cosm” -oselachus, in recognition of his contributions toward the acquisition and identification of numerous fossil chondrichthyans, as well as his indefatigable enthusiasm for all unusual vertebrates and many years of service to paleontology.
Allison W. Bronson, Alan Pradel, John S. S. Denton and John G. Maisey. 2024. A New operculate symmoriiform chondrichthyan from the Late Mississippian Fayetteville Shale (Arkansas, United States). GEODIVERSITAS. 46(4); 101-117.
sciencepress.mnhn.fr/en/periodiques/geodiversitas/46/4
twitter.com/AMNH/status/1765859348192915697
twitter.com/Kimi_Chap/status/1765729274294645095.
==========================
Cosmoselachus mehlingi
Bronson, Pradel, Denton & Maisey, 2024
sciencepress.mnhn.fr/en/periodiques/geodiversitas/46/4
twitter.com/AMNH
twitter.com/Kimi_Chap
We describe a new genus of symmoriiform chondrichthyan from the Late Mississippian Fayetteville Shale of Arkansas, United States, and include this fossil in a phylogenetic analysis of chondrichthyans. This taxon possesses elongate cartilaginous rays extending from the gill arches, forming an operculate structure that covers at least two of the branchial arches farther posteriorly. Although presence of a ‘hyoid operculum’ has been postulated in at least two unrelated Paleozoic sharks (e.g., Triodus, Tristychius), subsequent investigations failed to corroborate those claims. The new fossil therefore provides the first evidence of an endoskeletal operculum formed by elongate, fused pharyngeal arch rays in a chondrichthyan.
KEYWORDS: Chondrichthyes, Symmoriiformes, operculum, CT scanning, phylogeny, new genus, new species
An artist’s reconstruction of the new shark-like species Cosmoselachus mehlingi.
amnh.org
Class CHONDRICHTHYES Huxley, 1880
Order SYMMORIIFORMES Maisey, 2007
Family Falcatidae Zangerl, 1990
Genus Cosmoselachus n. gen.
Cosmoselachus mehlingi
Etymology: Cosmoselachus mehlingi n. gen., n. sp. is named in honor of American Museum of Natural History Senior Museum Specialist Carl Mehling, nickname “Cosm”, therefore “Cosm” -oselachus, in recognition of his contributions toward the acquisition and identification of numerous fossil chondrichthyans, as well as his indefatigable enthusiasm for all unusual vertebrates and many years of service to paleontology.
Allison W. Bronson, Alan Pradel, John S. S. Denton and John G. Maisey. 2024. A New operculate symmoriiform chondrichthyan from the Late Mississippian Fayetteville Shale (Arkansas, United States). GEODIVERSITAS. 46(4); 101-117.
sciencepress.mnhn.fr/en/periodiques/geodiversitas/46/4
twitter.com/AMNH/status/1765859348192915697
twitter.com/Kimi_Chap/status/1765729274294645095.
==========================
Garra hexagonarostris, a new labeonine fish (Teleostei: Cyprinidae) from the Chindwin basin, Manipur, Northeast India, and a critical review on the taxonomic status of G. minimus, G. alticaputus, G. nigricauda, G. kimini, and G. tyaoPISCESNEW SPECIESHEXAGON-SHAPED PROBOSCISCONICAL TUBERCLECHAKPI RIVEREASTERN HIMALAYAAbstractGarra hexagonarostris, a new member of the ‘proboscis species group’, is described from the Chakpi River of Chindwin basin in Manipur, India. The new species is distinguished by the following combination of characters: a prominent hexagon-shaped unilobed proboscis with five large-sized conical tubercles on anterior margin, and three or four medium-sized conical tubercles on anteroventral region; transverse lobe with 13−35 small- to medium-sized conical tubercles; lateral surface of snout swollen with 8−18 small- to medium-sized conical tubercles; 31−32 lateral-line scales including three pored scales on caudal fin; and a large arch-shaped black spot on each side of opercle, immediately anterior to upper angle of gill opening. The taxonomic status of several species of Garra from Arunachal Pradesh and Mizoram, is reviewed and accordingly Garra minimus is considered as a junior synonym of G. quadratirostris; G. nigricauda as a junior synonym of G. arunachalensis; G. alticaputus and G. kimini as junior synonyms of G. birostris; and G. tyao as a junior synonym of G. rakhinica.
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ISSUE: VOL. 5415 NO. 3: 22 FEB. 2024
TYPE: ARTICLE
PUBLISHED: 2024-02-22
DOI: 10.11646/ZOOTAXA.5415.3.6
PAGE RANGE: 466-476
ABSTRACT VIEWS: 8
PDF DOWNLOADED: 2
Luciobarbus lydianus and L. kottelati, two synonyms of L. graecus (Teleostei: Cyprinidae) PISCESAEGEAN BASINCOIFRESHWATER FISHMORPHOLOGYTAXONOMYWEST ASIA AbstractThe Aegean Luciobarbus graecus, L. lydianus, and L. kottelati were described based on morphological characters. However, re-examination of fresh material from the three species revealed greater intraspecific variability in morphological character states, and wider overlaps in all postulated diagnostic traits than initially documented. Consequently, it is not possible to identify and distinguish these three species based solely on morphological characteristics. As they also share identical COI barcode sequences, these species are now considered conspecifics, and L. lydianus and L. kottelati are treated as junior synonyms of L. graecus. The distribution of L. graecus remains a biogeographical puzzle, and it cannot be excluded that this could be partly human-mediated. Population-level genomic studies, particularly those focusing on phylogeography and population genetics, may help clarify mechanisms underlying contemporary distribution of this species.
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TYPE: ARTICLE
PUBLISHED: 2024-02-22
DOI: 10.11646/ZOOTAXA.5415.3.6
PAGE RANGE: 466-476
ABSTRACT VIEWS: 8
PDF DOWNLOADED: 2
Luciobarbus lydianus and L. kottelati, two synonyms of L. graecus (Teleostei: Cyprinidae) PISCESAEGEAN BASINCOIFRESHWATER FISHMORPHOLOGYTAXONOMYWEST ASIA AbstractThe Aegean Luciobarbus graecus, L. lydianus, and L. kottelati were described based on morphological characters. However, re-examination of fresh material from the three species revealed greater intraspecific variability in morphological character states, and wider overlaps in all postulated diagnostic traits than initially documented. Consequently, it is not possible to identify and distinguish these three species based solely on morphological characteristics. As they also share identical COI barcode sequences, these species are now considered conspecifics, and L. lydianus and L. kottelati are treated as junior synonyms of L. graecus. The distribution of L. graecus remains a biogeographical puzzle, and it cannot be excluded that this could be partly human-mediated. Population-level genomic studies, particularly those focusing on phylogeography and population genetics, may help clarify mechanisms underlying contemporary distribution of this species.
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Channa rakhinica, C. rubora, C. coccinea & C. pyrophthalmus • Four New Species of Channa (Teleostei: Labyrinthici: Channidae) from Myanmar
Channa pyrophthalmus,
Channa rakhinica,
Channa coccinea
Britz, Tan & Lukas, 2024
Raffles Bulletin of Zoology. 72
Abstract
We describe four new species of Channa from Myanmar, all members of the Gachua group. Channa rakhinica, new species, is a species endemic to west-flowing streams on the western slope of the Rakhine Yoma in Rakhine State; C. rubora, new species, occurs in mountain streams south of Mogaung, Kachin State; C. coccinea, new species, co-occurs with C. burmanica in streams north of Putao, also Kachin State, at the foothills of the Himalayas; and C. pyrophthalmus, new species, is found in streams in Tanintharyi Region at the southernmost tip of Myanmar, bordering Thailand. All four species are readily diagnosed by their colour pattern from other Gachua group taxa. They show genetic distances of 3.5–19.9% in the COI barcoding gene to other Myanmar members of the Gachua group.
Key words. snakehead fishes, Channoidei, Indo-Burman ranges, Tenasserim ranges, Himalayan foothills
Channa rakhinica, paratype, colouration in life, BMNH 2019.10.16.269–275, not measured, ca. 110 mm SL.
Channa rubora, paratype, colouration in life, Myanmar, Kachin State, unnamed stream south of Mogaung,BMNH 2019.10.16.195–206, not measured, ca. 90 mm SL.
Channa rakhinica, new species
Diagnosis. A member of the Gachua group readily distinguished from other Myanmar members by its colour pattern in life including reddish cheek, series of up to 5 semicircular concentric maroon pectoral bands wider than interbands, series of 6–7 saddle-like blotches, orange subdistal and white distal rim on dorsal- and caudal fins (vs. different colour pattern). It is further distinguished from C. stewartii by fewer dorsal-fin rays (34–38 vs. 39–41), and generally fewer anal-fin rays (23–25, rarely 22 or 26 vs. 26–27) and from C. burmanica by presence of pelvic fins (vs. absence). It also differs substantially from all Myanmar Gachua group snakeheads by a genetic distance of 12.9–18.5% in the COI gene.
Etymology. The species name is derived from the name of the area where it occurs, the Rakhine Yoma in western Myanmar, an adjective.
Remarks. This species has been traded as an ornamental fish since at least 2012 under the name “Channa sp. mimetic pulchra” and has been referred to as Channa sp. Rakhine Yoma in Conte-Grand et al. (2017) and Rüber et al. (2020). Aquarium reports suggest that this is a mouthbrooding species.
Channa rubora, new species
Diagnosis. A member of the Gachua group distinguished from all other Myanmar members except C. ornatipinnis, C. pulchra, and C. stewartii by the presence of numerous black spots on the head and body (vs absence). It differs from the latter by the size of the spots (tiny, a quarter of pupil size vs. almost pupil size or larger) and by its unique fin colouration in life, consisting of a pectoral fin with orange fin rays, a bluish proximal blotch and 3–6 brown distal semicircular concentric bands, of dorsal-, anal- and caudal-fins with a blue middle section of the fin membranes margined by a proximal dark brown and distal bright orange rim in the dorsal and caudal fins and white rim in the anal fin (vs different colour pattern). It also differs substantially from all Myanmar Gachua group snakeheads by a genetic distance of 11.6–19.3% in the COI gene.
Etymology. The species name, rubora, a noun in apposition, is derived from the Latin nouns ‘rubor’ for redness, and ‘ora’ for rim. The name was inspired by the orange-red rim of the dorsal and caudal fins.
Remarks. This species has been traded as an ornamental fish since at least 2012 under the name “Channa sp. red fin” and has been referred to as Channa sp. Mogaung in Conte-Grand et al. (2017) and Rüber et al. (2020). Aquarium reports suggest that this is a mouthbrooding species, in which larvae and small juveniles are of a yellow colour. Among the Gachua group species in Myanmar, C. rubora is readily distinguished from all other species by its colour pattern, specifically the numerous tiny spots on the head and flanks. It is also clearly distinguished from C. burmanica by presence of pelvic fins (vs. absence). From the other three species described in this paper, C. coccinea, C. pyrophthalmus, and C. rakhinica, C. rubora also differs in lacking caniniform teeth on the palatine and dentary.
Channa coccinea, colouration in life, ZRC 64932, 120.5 mm SL; Myanmar, Kachin State, unnamed stream near Putao.
Channa pyrophthalmus, colouration in life, ZRC 64934, 121.3 mm SL; Myanmar, Tanintharyi Region, Lon Phaw, tributary of Kra Buri.
Channa coccinea, new species
Diagnosis. Channa coccinea can be distinguished from all other Myanmar species of the Gachua group by its colour pattern consisting of oblique reddish saddle-like markings and lines (vs. different colour pattern). It can be distinguished from C. burmanica, which occurs in the same area, by presence of pelvic fins (vs absence). It also differs from all Myanmar Gachua group snakeheads by a genetic distance of 3.5–19.9% in the COI gene.
Distribution. The new species was found in streams near Putao, Kachin State, northern Myanmar.
Etymology. The species name is derived from the Latin adjective ‘coccineus’, -a , -um, red, alluding to the reddish markings on the head and sides of the body.
Remarks. This species has been traded as an ornamental fish since early 2022 under the name “Channa sp. ignis”. Its reproductive mode is still unknown, but it is likely a mouthbrooder.
Channa pyrophthalmus, new species (Figs. 14–16)
Diagnosis. Channa pyrophthalmus is distinguished from other Myanmar species of the Gachua group by the colour pattern of its head consisting of a bright orange suborbital patch combined with steel blue lips. It is further distinguished from them by generally having fewer dorsal- (32–34 vs. 34–40) and anal-fin rays (20–22 vs. 22–27) and vertebrae (40–41 vs. 41–48). It also differs substantially from all Myanmar Gachua group snakeheads by a genetic distance of 10.1–18.8% in the COI gene.
Distribution. The new species is known from the area around Lon Phaw, Kra Buri River drainage, southern Tanintharyi Region, close to the border with Thailand.
Etymology. The species name is derived from the Greek words πῦρ (pyr), fire, and ὀφθαλμός (ophthalmos), eye. It was inspired by the bright orange area under the eye, a colour reminiscent of that of glowing embers. Used as a noun in apposition.
Remarks. This species has been traded as an ornamental fish since 2009 under the name “Channa sp. ice & fire” or “Channa sp. fire and ice” and has been referred to as Channa sp. Tenasserim in Conte-Grand et al. (2017) and Rüber et al. (2020). Aquarium reports suggest that this is a mouthbrooding species. Among the Gachua group species in Myanmar, C. pyrophthalmus is readily distinguished from all other species by its colour pattern which includes a bright orange are around the eye combined with light blue lips and throat and a light blue margin of the anterior infraorbitals. Among Myanmar Gachua group snakehead fishes, it has the lowest dorsal- (32–34) and anal-fin ray (20–22), as well as vertebral counts (40–41).
Ralf Britz, Tan Heok Hui and Lukas. 2024. Four New Species of Channa from Myanmar (Teleostei, Labyrinthici, Channidae). Raffles Bulletin of Zoology. 72; Pp. 1–25.
==========================
Channa pyrophthalmus,
Channa rakhinica,
Channa coccinea
Britz, Tan & Lukas, 2024
Raffles Bulletin of Zoology. 72
Abstract
We describe four new species of Channa from Myanmar, all members of the Gachua group. Channa rakhinica, new species, is a species endemic to west-flowing streams on the western slope of the Rakhine Yoma in Rakhine State; C. rubora, new species, occurs in mountain streams south of Mogaung, Kachin State; C. coccinea, new species, co-occurs with C. burmanica in streams north of Putao, also Kachin State, at the foothills of the Himalayas; and C. pyrophthalmus, new species, is found in streams in Tanintharyi Region at the southernmost tip of Myanmar, bordering Thailand. All four species are readily diagnosed by their colour pattern from other Gachua group taxa. They show genetic distances of 3.5–19.9% in the COI barcoding gene to other Myanmar members of the Gachua group.
Key words. snakehead fishes, Channoidei, Indo-Burman ranges, Tenasserim ranges, Himalayan foothills
Channa rakhinica, paratype, colouration in life, BMNH 2019.10.16.269–275, not measured, ca. 110 mm SL.
Channa rubora, paratype, colouration in life, Myanmar, Kachin State, unnamed stream south of Mogaung,BMNH 2019.10.16.195–206, not measured, ca. 90 mm SL.
Channa rakhinica, new species
Diagnosis. A member of the Gachua group readily distinguished from other Myanmar members by its colour pattern in life including reddish cheek, series of up to 5 semicircular concentric maroon pectoral bands wider than interbands, series of 6–7 saddle-like blotches, orange subdistal and white distal rim on dorsal- and caudal fins (vs. different colour pattern). It is further distinguished from C. stewartii by fewer dorsal-fin rays (34–38 vs. 39–41), and generally fewer anal-fin rays (23–25, rarely 22 or 26 vs. 26–27) and from C. burmanica by presence of pelvic fins (vs. absence). It also differs substantially from all Myanmar Gachua group snakeheads by a genetic distance of 12.9–18.5% in the COI gene.
Etymology. The species name is derived from the name of the area where it occurs, the Rakhine Yoma in western Myanmar, an adjective.
Remarks. This species has been traded as an ornamental fish since at least 2012 under the name “Channa sp. mimetic pulchra” and has been referred to as Channa sp. Rakhine Yoma in Conte-Grand et al. (2017) and Rüber et al. (2020). Aquarium reports suggest that this is a mouthbrooding species.
Channa rubora, new species
Diagnosis. A member of the Gachua group distinguished from all other Myanmar members except C. ornatipinnis, C. pulchra, and C. stewartii by the presence of numerous black spots on the head and body (vs absence). It differs from the latter by the size of the spots (tiny, a quarter of pupil size vs. almost pupil size or larger) and by its unique fin colouration in life, consisting of a pectoral fin with orange fin rays, a bluish proximal blotch and 3–6 brown distal semicircular concentric bands, of dorsal-, anal- and caudal-fins with a blue middle section of the fin membranes margined by a proximal dark brown and distal bright orange rim in the dorsal and caudal fins and white rim in the anal fin (vs different colour pattern). It also differs substantially from all Myanmar Gachua group snakeheads by a genetic distance of 11.6–19.3% in the COI gene.
Etymology. The species name, rubora, a noun in apposition, is derived from the Latin nouns ‘rubor’ for redness, and ‘ora’ for rim. The name was inspired by the orange-red rim of the dorsal and caudal fins.
Remarks. This species has been traded as an ornamental fish since at least 2012 under the name “Channa sp. red fin” and has been referred to as Channa sp. Mogaung in Conte-Grand et al. (2017) and Rüber et al. (2020). Aquarium reports suggest that this is a mouthbrooding species, in which larvae and small juveniles are of a yellow colour. Among the Gachua group species in Myanmar, C. rubora is readily distinguished from all other species by its colour pattern, specifically the numerous tiny spots on the head and flanks. It is also clearly distinguished from C. burmanica by presence of pelvic fins (vs. absence). From the other three species described in this paper, C. coccinea, C. pyrophthalmus, and C. rakhinica, C. rubora also differs in lacking caniniform teeth on the palatine and dentary.
Channa coccinea, colouration in life, ZRC 64932, 120.5 mm SL; Myanmar, Kachin State, unnamed stream near Putao.
Channa pyrophthalmus, colouration in life, ZRC 64934, 121.3 mm SL; Myanmar, Tanintharyi Region, Lon Phaw, tributary of Kra Buri.
Channa coccinea, new species
Diagnosis. Channa coccinea can be distinguished from all other Myanmar species of the Gachua group by its colour pattern consisting of oblique reddish saddle-like markings and lines (vs. different colour pattern). It can be distinguished from C. burmanica, which occurs in the same area, by presence of pelvic fins (vs absence). It also differs from all Myanmar Gachua group snakeheads by a genetic distance of 3.5–19.9% in the COI gene.
Distribution. The new species was found in streams near Putao, Kachin State, northern Myanmar.
Etymology. The species name is derived from the Latin adjective ‘coccineus’, -a , -um, red, alluding to the reddish markings on the head and sides of the body.
Remarks. This species has been traded as an ornamental fish since early 2022 under the name “Channa sp. ignis”. Its reproductive mode is still unknown, but it is likely a mouthbrooder.
Channa pyrophthalmus, new species (Figs. 14–16)
Diagnosis. Channa pyrophthalmus is distinguished from other Myanmar species of the Gachua group by the colour pattern of its head consisting of a bright orange suborbital patch combined with steel blue lips. It is further distinguished from them by generally having fewer dorsal- (32–34 vs. 34–40) and anal-fin rays (20–22 vs. 22–27) and vertebrae (40–41 vs. 41–48). It also differs substantially from all Myanmar Gachua group snakeheads by a genetic distance of 10.1–18.8% in the COI gene.
Distribution. The new species is known from the area around Lon Phaw, Kra Buri River drainage, southern Tanintharyi Region, close to the border with Thailand.
Etymology. The species name is derived from the Greek words πῦρ (pyr), fire, and ὀφθαλμός (ophthalmos), eye. It was inspired by the bright orange area under the eye, a colour reminiscent of that of glowing embers. Used as a noun in apposition.
Remarks. This species has been traded as an ornamental fish since 2009 under the name “Channa sp. ice & fire” or “Channa sp. fire and ice” and has been referred to as Channa sp. Tenasserim in Conte-Grand et al. (2017) and Rüber et al. (2020). Aquarium reports suggest that this is a mouthbrooding species. Among the Gachua group species in Myanmar, C. pyrophthalmus is readily distinguished from all other species by its colour pattern which includes a bright orange are around the eye combined with light blue lips and throat and a light blue margin of the anterior infraorbitals. Among Myanmar Gachua group snakehead fishes, it has the lowest dorsal- (32–34) and anal-fin ray (20–22), as well as vertebral counts (40–41).
Ralf Britz, Tan Heok Hui and Lukas. 2024. Four New Species of Channa from Myanmar (Teleostei, Labyrinthici, Channidae). Raffles Bulletin of Zoology. 72; Pp. 1–25.
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ISSUE: VOL. 5403 NO. 3: 22 JAN. 2024
TYPE: CORRESPONDENCE
PUBLISHED: 2024-01-22
DOI: 10.11646/ZOOTAXA.5403.3.10
PAGE RANGE: 396-400
ABSTRACT VIEWS: 1
PDF DOWNLOADED: 0
Range extension of the Honduran endemic killifish Tlaloc portillorum (Matamoros & Schaefer 2010) (Cyprinodontiformes: Profundulidae): new records from the upper reaches of the Patuca and Choluteca Rivers PISCESCYPRINODONTIFORMESPROFUNDULIDAETLALOC PORTILLORUMPATUCA AND CHOLUTECA RIVERS
NO FURTHER INFORMATION AT THE MOMENT
TYPE: CORRESPONDENCE
PUBLISHED: 2024-01-22
DOI: 10.11646/ZOOTAXA.5403.3.10
PAGE RANGE: 396-400
ABSTRACT VIEWS: 1
PDF DOWNLOADED: 0
Range extension of the Honduran endemic killifish Tlaloc portillorum (Matamoros & Schaefer 2010) (Cyprinodontiformes: Profundulidae): new records from the upper reaches of the Patuca and Choluteca Rivers PISCESCYPRINODONTIFORMESPROFUNDULIDAETLALOC PORTILLORUMPATUCA AND CHOLUTECA RIVERS
NO FURTHER INFORMATION AT THE MOMENT
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Redescription and first Japanese seamount record of Stethopristes eos (Zeiformes; Parazenidae)PISCESKAGARIBI-MATODAINEW STANDARD JAPANESE NAMETELEOSTEIDEEP-SEAMARINE PROTECTED AREAAbstractDuring a biodiversity survey conducted in 2020, focusing on seamounts located in the southern region of Japan, specifically designated as marine protected areas, a single specimen of Stethopristes eos Gilbert, 1905 measuring 124.2 mm in standard length was obtained via the use of a remotely operated vehicle (ROV). The collection occurred at a depth of 519 meters on the Ritto Seamount, located along the western Mariana Ridge. However, this species is poorly known, with only a limited dataset available concerning its morphology. In this study, we present a comprehensive redescription of the species, utilizing information obtained from the type specimens and a newly discovered specimen from Japanese waters. The Japanese specimen constitutes the first recorded occurrence of this species within the western Pacific Ocean. As part of this redescription, we suggest new standard Japanese names for both the genus and species.
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ISSUE: VOL. 5399 NO. 2: 11 JAN. 2024
TYPE: ARTICLE
PUBLISHED: 2024-01-11
DOI: 10.11646/ZOOTAXA.5399.2.7
PAGE RANGE: 181-189
ABSTRACT VIEWS: 203
PDF DOWNLOADED: 6
Description of a rock-dwelling cichlid that re-invaded the sand substrate in Lake Malaŵi, AfricaPISCESMBUNASAND-DWELLING CICHLIDPSEUDOTROPHEUSLIKOMA ISLANDAbstractPseudotropheus Regan had been a catch-all genus for many of the rock-dwelling cichlids of Lake Malaŵi, known as mbuna, for over half a century. Although many of the species previously assigned to this genus have since been allocated to other genera there are still about a dozen species in the genus that do not appear to be closely related to its type species, P. williamsi, but for which no better placement could be found. Pseudotropheus livingstonii (Boulenger) is one such species and the new species described herein appears to be closely related and has for that reason been temporarily assigned to Pseudotropheus. Pseudotropheus likomae n. sp. from Likoma Island can be diagnosed from all other Pseudotropheus spp., by having five or fewer distinct vertical bars below the dorsal fin and two horizontal stripes in mature individuals.
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TYPE: ARTICLE
PUBLISHED: 2024-01-11
DOI: 10.11646/ZOOTAXA.5399.2.7
PAGE RANGE: 181-189
ABSTRACT VIEWS: 203
PDF DOWNLOADED: 6
Description of a rock-dwelling cichlid that re-invaded the sand substrate in Lake Malaŵi, AfricaPISCESMBUNASAND-DWELLING CICHLIDPSEUDOTROPHEUSLIKOMA ISLANDAbstractPseudotropheus Regan had been a catch-all genus for many of the rock-dwelling cichlids of Lake Malaŵi, known as mbuna, for over half a century. Although many of the species previously assigned to this genus have since been allocated to other genera there are still about a dozen species in the genus that do not appear to be closely related to its type species, P. williamsi, but for which no better placement could be found. Pseudotropheus livingstonii (Boulenger) is one such species and the new species described herein appears to be closely related and has for that reason been temporarily assigned to Pseudotropheus. Pseudotropheus likomae n. sp. from Likoma Island can be diagnosed from all other Pseudotropheus spp., by having five or fewer distinct vertical bars below the dorsal fin and two horizontal stripes in mature individuals.
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Luciogobius griseus • A New subtropical Species of Goby of the Genus Luciogobius (Gobiiformes: Gobiidae) from southwestern Japan
Luciogobius griseus
Koreeda, Maeda & Motomura, 2023
DOI: 10.11646/zootaxa.5361.3.5
kagoshima-u.ac.jp
Abstract
Luciogobius griseus n. sp., belonging to the Luciogobius platycephalus complex, is described on the basis of 40 specimens from the Nansei Islands, southwestern Japan (subtropical area). The new species is generally found in intertidal gravel sediments subjected to freshwater runoff from springs on coastal lines or river mouths and is characterized by the following combination of characters: total second dorsal-fin rays 9–12 (modally 11); total anal-fin rays usually 12–14 (modally 13); pectoral-fin rays 12–15 (modally 13); vertebrae 17 or 18 + 23 or 24 = 40–42 (18 + 23 = 41); uppermost 2–4 (2–3) rays on pectoral fin free; 8–12 pectoral-fin rays branched (uppermost free rays and sometimes lowermost ray unbranched); pectoral-fin membrane not strongly concave anteriorly (except for free rays); pelvic fins united, forming a disk; head relatively short, 13.9–20.8% of standard length (SL); relatively short pre-pelvic fin, length 14.4–22.1% of SL; relatively long pre-dorsal fin, length 68.9–72.9% of SL; relatively long pre-anal fin, length 63.5–67.7% of SL; relatively short pelvic fin, length 2.8–4.7% of SL; distance between posterior end of pelvic fin and anus relatively long, 32.0–36.4% of SL (aforementioned morphometrics each distinguishing L. griseus n. sp. from other species in the L. platycephalus complex); and fresh specimens with greenish dark brown or gray body. A key to the L. platycephalus complex is provided, together with limited descriptions and remarks on the other two members of the complex.
Keywords: Pisces, actinopterygii, teleostei, Nansei Islands, osumi Line
Reo Koreeda, Ken Maeda and Hiroyuki Motomura. 2023. A New subtropical Species of Goby of the Genus Luciogobius (Gobiidae) from southwestern Japan. Zootaxa. 5361(3); 390-408. DOI: 10.11646/zootaxa.5361.3.5
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Luciogobius griseus
Koreeda, Maeda & Motomura, 2023
DOI: 10.11646/zootaxa.5361.3.5
kagoshima-u.ac.jp
Abstract
Luciogobius griseus n. sp., belonging to the Luciogobius platycephalus complex, is described on the basis of 40 specimens from the Nansei Islands, southwestern Japan (subtropical area). The new species is generally found in intertidal gravel sediments subjected to freshwater runoff from springs on coastal lines or river mouths and is characterized by the following combination of characters: total second dorsal-fin rays 9–12 (modally 11); total anal-fin rays usually 12–14 (modally 13); pectoral-fin rays 12–15 (modally 13); vertebrae 17 or 18 + 23 or 24 = 40–42 (18 + 23 = 41); uppermost 2–4 (2–3) rays on pectoral fin free; 8–12 pectoral-fin rays branched (uppermost free rays and sometimes lowermost ray unbranched); pectoral-fin membrane not strongly concave anteriorly (except for free rays); pelvic fins united, forming a disk; head relatively short, 13.9–20.8% of standard length (SL); relatively short pre-pelvic fin, length 14.4–22.1% of SL; relatively long pre-dorsal fin, length 68.9–72.9% of SL; relatively long pre-anal fin, length 63.5–67.7% of SL; relatively short pelvic fin, length 2.8–4.7% of SL; distance between posterior end of pelvic fin and anus relatively long, 32.0–36.4% of SL (aforementioned morphometrics each distinguishing L. griseus n. sp. from other species in the L. platycephalus complex); and fresh specimens with greenish dark brown or gray body. A key to the L. platycephalus complex is provided, together with limited descriptions and remarks on the other two members of the complex.
Keywords: Pisces, actinopterygii, teleostei, Nansei Islands, osumi Line
Reo Koreeda, Ken Maeda and Hiroyuki Motomura. 2023. A New subtropical Species of Goby of the Genus Luciogobius (Gobiidae) from southwestern Japan. Zootaxa. 5361(3); 390-408. DOI: 10.11646/zootaxa.5361.3.5
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SSUE: VOL. 5399 NO. 1: 10 JAN. 2024
TYPE: ARTICLE
PUBLISHED: 2024-01-10
DOI: 10.11646/ZOOTAXA.5399.1.3
PAGE RANGE: 37-51
ABSTRACT VIEWS: 1
PDF DOWNLOADED: 0
The first record of Egglestonichthys bombylios (Gobiiformes: Gobiidae) from China with its first fresh colouration informationPISCESEGGLESTONE’S BUMBLEBEE GOBYFIRST RECORDMORPHOLOGYMITOCHONDRIAL GENOMEFUJIANZHEJIANGSOUTH CHINA SEAAbstractDuring bottom trawl surveys carried out between 2013–2021, 52 specimens (33.8–54.0 mm SL) of Egglestone’s bumblebee goby Egglestonichthys bombylios were collected at a depth of 1.5–15 m from Dongshan Bay, Sanmen Bay, and Niushan Island, China. They represent the first records of this species from China. A full description, including fresh colouration of the species is provided as it is poorly known. The individuals collected in China agree with most morphological features of the holotype, except for the pelvic fin fraenum that was not observed or appears to be absent in most specimens. A strong relationship between E. bombylios, Larsonella pumilus, and the genus Priolepis is herein demonstrated by the mitochondrial genome sequences of E. bombylios and twenty closely related species. This study enriches the existing genetic data of the so-called Priolepis lineage and provides useful insights into the phylogenetic relationships across species of the genera Egglestonichthys, Priolepis, and Larsonella.
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TYPE: ARTICLE
PUBLISHED: 2024-01-10
DOI: 10.11646/ZOOTAXA.5399.1.3
PAGE RANGE: 37-51
ABSTRACT VIEWS: 1
PDF DOWNLOADED: 0
The first record of Egglestonichthys bombylios (Gobiiformes: Gobiidae) from China with its first fresh colouration informationPISCESEGGLESTONE’S BUMBLEBEE GOBYFIRST RECORDMORPHOLOGYMITOCHONDRIAL GENOMEFUJIANZHEJIANGSOUTH CHINA SEAAbstractDuring bottom trawl surveys carried out between 2013–2021, 52 specimens (33.8–54.0 mm SL) of Egglestone’s bumblebee goby Egglestonichthys bombylios were collected at a depth of 1.5–15 m from Dongshan Bay, Sanmen Bay, and Niushan Island, China. They represent the first records of this species from China. A full description, including fresh colouration of the species is provided as it is poorly known. The individuals collected in China agree with most morphological features of the holotype, except for the pelvic fin fraenum that was not observed or appears to be absent in most specimens. A strong relationship between E. bombylios, Larsonella pumilus, and the genus Priolepis is herein demonstrated by the mitochondrial genome sequences of E. bombylios and twenty closely related species. This study enriches the existing genetic data of the so-called Priolepis lineage and provides useful insights into the phylogenetic relationships across species of the genera Egglestonichthys, Priolepis, and Larsonella.
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Cracking the glass-perchlet code: Integrative taxonomy uncovers high species-level diversity within the glass-perchlet genus Ambassis (Ambassidae) in tropical AsiaSiti Zafirah Ghazali, Sébastien Lavoué, Norli Fauzani Mohd Abu Hassan Alshari, Danial Hariz Zainal Abidin, Jamsari Amirul Firdaus Jamaluddin, Min Pau Tan, Siti Azizah Mohd Nor
First published: 11 December 2023
https://doi.org/10.1111/zsc.12640
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SHAREAbstractGlass-perchlets of the genus Ambassis (Teleostei; Ambassidae) form an important component of the brackish and marine coastal fish communities of tropical Asia. However, their species-level diversity is still poorly documented because of the absence of recent taxonomic revisions in this region and the limited availability of specimens for research. In addition, long-standing taxonomic and nomenclatural issues complicate the studies of this genus. Herein, we examine the diversity of Ambassis in Peninsular Malaysia using an integrative taxonomic approach and a large set of recently collected specimens from this region. Our initial morphological observations of 260 specimens revealed the presence of eight species, identified as Ambassis dussumieri, Ambassis interrupta, Ambassis kopsii, Ambassis macracanthus, Ambassis nalua, Ambassis octava, Ambassis urotaenia and Ambassis vachellii. We then sequenced the barcode fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene for 122 of our specimens, representing all eight morpho-species. Automatic species delimitation methods recovered nine Molecular Operational Taxonomic Units (MOTUs) because A. interrupta is made of two MOTUs. Morphological re-examination within A. interrupta detected variation at one character, congruent with molecular delimitation. Overall, our integrative approach unveiled rich species-level diversity within the genus Ambassis in Peninsular Malaysia, with the presence of nine species. Further comparisons between our COI dataset and the COI sequences archived in the Barcode of Life Data System (BOLD) from specimens of Ambassis broadly collected in tropical Asian regions, indicated regional-scale hidden diversity and identification conflicts, triggering the need for a complete taxonomic revision of this genus.
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First published: 11 December 2023
https://doi.org/10.1111/zsc.12640
Read the full text
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SHAREAbstractGlass-perchlets of the genus Ambassis (Teleostei; Ambassidae) form an important component of the brackish and marine coastal fish communities of tropical Asia. However, their species-level diversity is still poorly documented because of the absence of recent taxonomic revisions in this region and the limited availability of specimens for research. In addition, long-standing taxonomic and nomenclatural issues complicate the studies of this genus. Herein, we examine the diversity of Ambassis in Peninsular Malaysia using an integrative taxonomic approach and a large set of recently collected specimens from this region. Our initial morphological observations of 260 specimens revealed the presence of eight species, identified as Ambassis dussumieri, Ambassis interrupta, Ambassis kopsii, Ambassis macracanthus, Ambassis nalua, Ambassis octava, Ambassis urotaenia and Ambassis vachellii. We then sequenced the barcode fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene for 122 of our specimens, representing all eight morpho-species. Automatic species delimitation methods recovered nine Molecular Operational Taxonomic Units (MOTUs) because A. interrupta is made of two MOTUs. Morphological re-examination within A. interrupta detected variation at one character, congruent with molecular delimitation. Overall, our integrative approach unveiled rich species-level diversity within the genus Ambassis in Peninsular Malaysia, with the presence of nine species. Further comparisons between our COI dataset and the COI sequences archived in the Barcode of Life Data System (BOLD) from specimens of Ambassis broadly collected in tropical Asian regions, indicated regional-scale hidden diversity and identification conflicts, triggering the need for a complete taxonomic revision of this genus.
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Fishes of the highlands and escarpments of Angola and Namibia PH Skelton
URL: https://www.nje.org.na/.../nje/article/view/volume8-skelton Published online: 15th December 2023
URL: https://www.nje.org.na/.../nje/article/view/volume8-skelton Published online: 15th December 2023
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A taxonomic review of the Neotropical electric fish Rhamphichthys (Gymnotiformes: Rhamphichthyidae)
AUTHORSHIPSCIMAGO INSTITUTIONS RANKINGSAbstractThe species diversity and taxonomy of Rhamphichthys is reviewed and seven species are considered valid: Rhamphichthys apurensis from the Orinoco and Cuyuni river basins; R. drepanium from the Amazon and Orinoco river basins; R. hahni from the Paraná-Paraguay River system; R. heleios and R. lineatus from the Amazon River basin; R. pantherinus from theupper Orinoco, Essequibo, Amazon and coastal rivers of North Brazil,and R. rostratus from the upper Orinoco, Amazon and coastal rivers of Guianas. Based on the examination of specimens from nominal species, from across their geographic ranges, including specimen types, the previous synonymization of four species (R. blochii, R. reinhardti, R. schomburgki, and R. schneideri)with R. rostratus,and R. marmoratus with R. pantherinus is confirmed. Two other nominal species, R. atlanticus and R. longior, are proposed as junior synonyms of R. pantherinus.Species are redescribed and diagnosed based on color pattern, morphometric, meristic, and internal anatomy characters.Distribution maps and an identification key based on the examination of a comprehensive list of materials are also provided
LINK
doi.org/10.1590/1982-0224-2023-0012
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AUTHORSHIPSCIMAGO INSTITUTIONS RANKINGSAbstractThe species diversity and taxonomy of Rhamphichthys is reviewed and seven species are considered valid: Rhamphichthys apurensis from the Orinoco and Cuyuni river basins; R. drepanium from the Amazon and Orinoco river basins; R. hahni from the Paraná-Paraguay River system; R. heleios and R. lineatus from the Amazon River basin; R. pantherinus from theupper Orinoco, Essequibo, Amazon and coastal rivers of North Brazil,and R. rostratus from the upper Orinoco, Amazon and coastal rivers of Guianas. Based on the examination of specimens from nominal species, from across their geographic ranges, including specimen types, the previous synonymization of four species (R. blochii, R. reinhardti, R. schomburgki, and R. schneideri)with R. rostratus,and R. marmoratus with R. pantherinus is confirmed. Two other nominal species, R. atlanticus and R. longior, are proposed as junior synonyms of R. pantherinus.Species are redescribed and diagnosed based on color pattern, morphometric, meristic, and internal anatomy characters.Distribution maps and an identification key based on the examination of a comprehensive list of materials are also provided
LINK
doi.org/10.1590/1982-0224-2023-0012
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Parascolopsis akatamae • A New Species of Dwarf Monocle Bream (Perciformes: Nemipteridae) from the Indo-West Pacific, with Redescription of closely related Species P. eriomma
[A] Parascolopsis akatamae n. sp. Miyamoto, McMahan & Kaneko, 2020
[B] P. eriomma (Jordan & Richardson, 1909)
DOI: 10.11646/zootaxa.4881.1.6
Abstract
A new species of dwarf monocle bream, Parascolopsis akatamae n. sp., is described from the Indo-West Pacific. The new species is distinguished from all other species of Parascolopsis in having 16–19 gill rakers on the first arch, length of forked part of caudal fin 5.8–6.5 times in standard length, eye diameter 1.3–1.8 times in length of the longest dorsal-fin spine, and a pale yellow stripe present from lower edge of the eye to posterior edge of the preopercle. Parascolopsis eriomma (Jordan & Richardson, 1909) is morphologically very similar to the new species and the two have been confused with each other for a long time. Therefore, we redescribe P. eriomma based on the holotype and newly collected specimens. In addition, we found that patterns of biofluorescence emission for both species are clearly different. This suggests that their biofluorescence patterns may function in distinguishing each other.
Keywords: Pisces, Actinopterygii, Taxonomy, biofluorescence
Parascolopsis akatamae n. sp. (A) and P. eriomma (B–C).
A) fresh specimen, OCF-P4098, holotype, 160.5 mm SL, Okinawa-jima Island, Japan;
B) fresh specimen, OCF-P4097, 154.4 mm SL, Okinawa-jima Island, Japan;
C) preserved specimen, FMNH 52247, holotype, 190.9 mm SL, Kaohsiung, Taiwan.
Fresh specimens of Parascolopsis akatamae n. sp. (A–D) and P. eriomma (E–F) at different growth stages.
A) OCF-P4119, 98.3 mm SL, Okinawa-jima Island, Japan; B) OCF-P4071, 140.1 mm SL, Okinawa-jima Island, Japan; C) OCF-P4123, 179.7 mm SL, Okinawa-jima Island, Japan; D) OCF-P4089, 252.7 mm SL, Ishigaki-jima Island, Japan;
E) OCF-P4212, 139.6 mm SL, Okinawa-jima Island, Japan; F) OCF-P3889, 172.8 mm SL, Okinawa-jima Island, Japan.
Parascolopsis akatamae n. sp.
[English name: Rosy dwarf monocle bream;
Standard Japanese name: Aka-tamagashira]
Diagnosis. Distinguished from congeners by the following combination of characters: gill rakers on first arch 16–19; caudal fin lightly forked, length of forked part of caudal fin 5.8–6.5 times in SL (Figs. 1A, 2A–D, 3A); eye diameter 1.3–1.8 times in length of longest dorsal-fin spine (Fig. 3B); pale yellow stripe present from lower edge of the eye to posterior edge of the preopercle (Figs. 1A, 2A–D); strong biofluorescence emission observed on isthmus and branchiostegal membrane (Fig. 4A–C) (see paragraph of biofluorescence emission patterns).
Etymology. Parascolopsis akatamae n. sp. has long been confused with P. eriomma. P. akatamae is more widely distributed than P. eriomma (Fig. 5), and more common at least in Japan and Taiwan (Hung et al. 2016; this study). Therefore, the English name “Rosy dwarf monocle bream” and Japanese name “Aka-tamagashira” previously used for P. eriomma more appropriately applies to the new species to avoid unnecessary confusion. The specific epithet “akatamae” is derived from the local name in Japan of the type locality.
Parascolopsis eriomma (Jordan & Richardson, 1909)
[New English name: Swallowtail dwarf monocle bream;
New standard Japanese name: Ennbi-aka-tamagashira]
Etymology. Previously, the English name “Rosy dwarf monocle bream” and Japanese name “Aka-tamagashi-ra” were used for P. eriomma. However, this study revealed that previously recognized P. eriomma included P. akatamae n. sp. This species is more narrowly distributed than P. akatamae (Fig. 5) and very rare at least in Japan and Taiwan (Hung et al. 2016; this study). Therefore, the English name “Rosy dwarf monocle bream” and Japanese name “Aka-tamagashira,” which were previously used for P. eriomma, were applied to P. akatamae, and a new English name, “Swallowtail dwarf monocle bream” and new standard Japanese name, “Ennbi-aka-tamagashira” have been applied to this P. eriomma. The Japanese “Ennbi” means tail of swallow and is derived from shape of the caudal fin of the species.
Biofluorescence emission patterns of Parascolopsis akatamae n. sp. (A–C, OCF-P4098, holotype, 160.5 mm SL) and P. eriomma (D–F, OCF-P4097, 154.4 mm SL).
A,D) lateral view, under white light; B,E) lateral view, under blue light; C,F) ventral view, under blue light.
Kei Miyamoto, Caleb D. McMahan and Atsushi Kaneko. 2020. Parascolopsis akatamae, A New Species of Dwarf Monocle Bream (Perciformes: Nemipteridae) from the Indo-West Pacific, with Redescription of closely related Species P. eriomma. Zootaxa. 4881(1); 91–103. DOI: 10.11646/zootaxa.4881.1.6
twitter.com/gobysimon/status/1331311975188602883
==========================
[A] Parascolopsis akatamae n. sp. Miyamoto, McMahan & Kaneko, 2020
[B] P. eriomma (Jordan & Richardson, 1909)
DOI: 10.11646/zootaxa.4881.1.6
Abstract
A new species of dwarf monocle bream, Parascolopsis akatamae n. sp., is described from the Indo-West Pacific. The new species is distinguished from all other species of Parascolopsis in having 16–19 gill rakers on the first arch, length of forked part of caudal fin 5.8–6.5 times in standard length, eye diameter 1.3–1.8 times in length of the longest dorsal-fin spine, and a pale yellow stripe present from lower edge of the eye to posterior edge of the preopercle. Parascolopsis eriomma (Jordan & Richardson, 1909) is morphologically very similar to the new species and the two have been confused with each other for a long time. Therefore, we redescribe P. eriomma based on the holotype and newly collected specimens. In addition, we found that patterns of biofluorescence emission for both species are clearly different. This suggests that their biofluorescence patterns may function in distinguishing each other.
Keywords: Pisces, Actinopterygii, Taxonomy, biofluorescence
Parascolopsis akatamae n. sp. (A) and P. eriomma (B–C).
A) fresh specimen, OCF-P4098, holotype, 160.5 mm SL, Okinawa-jima Island, Japan;
B) fresh specimen, OCF-P4097, 154.4 mm SL, Okinawa-jima Island, Japan;
C) preserved specimen, FMNH 52247, holotype, 190.9 mm SL, Kaohsiung, Taiwan.
Fresh specimens of Parascolopsis akatamae n. sp. (A–D) and P. eriomma (E–F) at different growth stages.
A) OCF-P4119, 98.3 mm SL, Okinawa-jima Island, Japan; B) OCF-P4071, 140.1 mm SL, Okinawa-jima Island, Japan; C) OCF-P4123, 179.7 mm SL, Okinawa-jima Island, Japan; D) OCF-P4089, 252.7 mm SL, Ishigaki-jima Island, Japan;
E) OCF-P4212, 139.6 mm SL, Okinawa-jima Island, Japan; F) OCF-P3889, 172.8 mm SL, Okinawa-jima Island, Japan.
Parascolopsis akatamae n. sp.
[English name: Rosy dwarf monocle bream;
Standard Japanese name: Aka-tamagashira]
Diagnosis. Distinguished from congeners by the following combination of characters: gill rakers on first arch 16–19; caudal fin lightly forked, length of forked part of caudal fin 5.8–6.5 times in SL (Figs. 1A, 2A–D, 3A); eye diameter 1.3–1.8 times in length of longest dorsal-fin spine (Fig. 3B); pale yellow stripe present from lower edge of the eye to posterior edge of the preopercle (Figs. 1A, 2A–D); strong biofluorescence emission observed on isthmus and branchiostegal membrane (Fig. 4A–C) (see paragraph of biofluorescence emission patterns).
Etymology. Parascolopsis akatamae n. sp. has long been confused with P. eriomma. P. akatamae is more widely distributed than P. eriomma (Fig. 5), and more common at least in Japan and Taiwan (Hung et al. 2016; this study). Therefore, the English name “Rosy dwarf monocle bream” and Japanese name “Aka-tamagashira” previously used for P. eriomma more appropriately applies to the new species to avoid unnecessary confusion. The specific epithet “akatamae” is derived from the local name in Japan of the type locality.
Parascolopsis eriomma (Jordan & Richardson, 1909)
[New English name: Swallowtail dwarf monocle bream;
New standard Japanese name: Ennbi-aka-tamagashira]
Etymology. Previously, the English name “Rosy dwarf monocle bream” and Japanese name “Aka-tamagashi-ra” were used for P. eriomma. However, this study revealed that previously recognized P. eriomma included P. akatamae n. sp. This species is more narrowly distributed than P. akatamae (Fig. 5) and very rare at least in Japan and Taiwan (Hung et al. 2016; this study). Therefore, the English name “Rosy dwarf monocle bream” and Japanese name “Aka-tamagashira,” which were previously used for P. eriomma, were applied to P. akatamae, and a new English name, “Swallowtail dwarf monocle bream” and new standard Japanese name, “Ennbi-aka-tamagashira” have been applied to this P. eriomma. The Japanese “Ennbi” means tail of swallow and is derived from shape of the caudal fin of the species.
Biofluorescence emission patterns of Parascolopsis akatamae n. sp. (A–C, OCF-P4098, holotype, 160.5 mm SL) and P. eriomma (D–F, OCF-P4097, 154.4 mm SL).
A,D) lateral view, under white light; B,E) lateral view, under blue light; C,F) ventral view, under blue light.
Kei Miyamoto, Caleb D. McMahan and Atsushi Kaneko. 2020. Parascolopsis akatamae, A New Species of Dwarf Monocle Bream (Perciformes: Nemipteridae) from the Indo-West Pacific, with Redescription of closely related Species P. eriomma. Zootaxa. 4881(1); 91–103. DOI: 10.11646/zootaxa.4881.1.6
twitter.com/gobysimon/status/1331311975188602883
==========================
Balitora anlongensis, the first cavefish species of the genus Balitora (Teleostei, Balitoridae) from Guizhou Province, southwest China
Tao Luo, Zhi-Xia Chen, Xin-Rui Zhao, Jing Yu, Chang-Ting Lan, Jia-Jun Zhou, Ning Xiao, Jiang ZhouAbstractThis work describes a new species, Balitora anlongensis sp. nov., collected from a cave at Xinglong Town, Anlong County, Guzihou, China. Phylogenetic trees reconstructed based on two mitochondrial and three nuclear genes show that the new species represents an independent evolutionary lineage with large genetic differences, 7.1%–12.0% in mitochondrial gene cytochrome b and 9.2%–12.1% in cytochrome oxidase subunit 1, from congeners. Morphologically, the new species can be distinguished from the 18 species currently assigned to the genus Balitora by a combination of characters, most clearly by having two pairs of maxillary barbels; 8½ branched dorsal-fin rays; 5½ branched anal-fin rays; pectoral fin not reaching pelvic fin origin; dorsal-fin origin in front of pelvic fin origin; eye small (eye diameter approximately equal to outer maxillary barbel length); and fins lacking pigment in live fish. The new species represents the first record of Balitora inhabiting caves in China and increases the number of species in the genus Balitora in its present concept from 18 to 19. The study suggests that more evidence is needed to further clarify the taxonomic composition of the genus Balitora.
Key wordsNanpanjiang River, stone loach, taxonomy, phylogeny
IntroductionThe karst region of southwest China is well known as a distinctive center and hotspot of biodiversity (Myers et al. 2000). Distinctive karst habitats have created varied natural landscapes and organisms, such as cave river ecosystems and the organisms that inhabit them. Cavefishes are typical cave organisms (Niemiller et al. 2019). In China, there are approximately 170 endemic species of cavefishes belonging to two orders (Cypriniformes and Siluriformes) and four families (Cyprinidae, Nemacheilidae, Cobitidae, and Amblycipitidae) (Ma et al. 2019). In previous reports, cavefishes were mainly recorded in the Cyprinidae (83 species), Nemacheilidae (77 species), and Cobitidae (eight species) (Ma et al. 2019) (Suppl. material 1). New discoveries may be possible at the family, genus, and species level, considering that past surveys and reports of cavefishes have mainly focused on Guangxi and Yunnan provinces, China (Ma et al. 2019).
The genus Balitora, Gray, 1830 was established with Balitora brucei as the type species, originally placed in the Cobitidae (Gray, 1830), and is now placed within the Balitoridae (Fricke et al. 2023). Hemimyzon Regan, 1911 and Sinohomaloptera Fang, 1930, which are taxonomically closely related to Balitora, were established using H. formosanum and S. kwangsiensis, respectively, as the type species. The genus Balitora has long been the subject of taxonomic controversy, with different taxonomic schemes proposed based on morphological differences. Chen (1978) recognized one pair of maxillary barbels as a character that distinguishes Balitora from other genera. Later, several new Balitora species were reported, including B. pengi Huang, 1982, B. tchangi Zheng, 1982, B. nujiangensis Zhang & Zheng, 1983, and B. elongata Chen & Li, 1985 (Zheng et al. 1982; Zheng and Zhang 1983; Li and Chen 1985), which are currently placed in the genus Hemimyzon (Kottelat and Chu 1988). Kottelat and Chu (1988) and Kottelat (1988) reviewed the genus and considered Sinohomaloptera to be a synonym of Balitora as having one or two pairs of maxillary barbels. Based on three or more unbranched pelvic fin rays, B. pengi, B. tchangi, B. nujiangensis, and B. elongata were placed in Hemimyzon, while species with two branched pelvic fin rays were placed in Balitora, namely B. lancangjiangensis (Zheng, 1980), B. kwangsiensis (Fang, 1930), and B. longibarbata (Chen, 1982) (Kottelat and Chu 1988). Chen (1990) accepted this suggestion for a taxonomic revision of the species distributed in Yunnan. However, the suggestion of Kottelat and Chu (1988) was not adopted by Chinese scholars, and species were still placed in Balitora based on the number of maxillary barbel, and Sinohomaloptera was considered valid (Chen and Tang 2000; Jiang et al. 2016). Nevertheless, previous morphology-based studies have not resolved the phylogenetic relationships between Balitora, Hemimyzon and Sinohomaloptera due to a lack of molecular evidence.
Few molecular markers have been used to assess the phylogeny of the genus Balitora. A phylogenetic tree reconstructed by Šlechtová et al. (2007) based on the nuclear gene RAG1 showed that a species identified as Balitora sp. cf. burmanica showed that the genus Balitora is nested within the genus Homaloptera. The phylogeny of Liu et al. (2012a) based on mitochondrial (COI and ND4+ND5) and nuclear genes (RH1, RAG1, EGR2B, and IRBP), on the other hand, supports the view that Balitora (S. kwangsiensis) is close to Sinogastromyzon. Kumkar et al. (2016a) used two mitochondria (COI and Cyt b) to show for the first time phylogenetically that Balitora is not a monophyletic, but can be divided into three major clades. Keskar et al. (2018) then supported Balitora as a sister clade of Lepidocephalichthys based on mitochondrial COI and Cyt b. Tao et al. (2019) recovered Balitora (only B. elongata) as a sister clade of Sinohomaloptera (only S. kwangsiensis) based on a large-scale phylogeny of one mitochondrial and 14 nuclear genes. More recently, a phylogeny based on the mitochondrial genome (only B. ludongensis Liu & Chen, 2012) strongly support Balitora being close to ((Jinshaia + Lepturichthys) + Sinogastromyzon) (Shao et al. 2020). Based on the above various studies, it can be concluded that the phylogenetic position of the genus Balitora is unclear and may not be monophyletic.
To date, the classification of the genus remains controversial, mainly because of the lack of clear phylogenetic relationships and stable morphological characters among Balitora, Hemimyzon, and Sinohomaloptera (Table 1). In this study, we followed the latest taxonomic scheme after a comprehensive review, and Balitora was recorded with 19 species (Table 1), of which ten species are distributed in China, namely B. brucei Gray, 1830, B. burmanica Hora, 1932, B. elongata, B. kwangsiensis, B. lancangjiangensis, B. longibarbata, B. ludongensis, B. nantingensis Chen, Cui & Yang, 2005, B. meridionalis Kottelat, 1988, and B. tchangi (Liu et al. 2012b; Jiang et al. 2016) (Table 1). However, because this work did not have access to the original data for the four species (B. haithanhi, B. nigrocorpa, B. vanlani, and B. vanlongi) described by Nguyen (2005), as well as because B. haithanhi Nguyen, 2005, B. nigrocorpa Nguyen, 2005, and B. vanlani Nguyen, 2005 were used as synonyms of B. kwangsiensis and B. vanlongi was used as a synonym of B. lancangjiangensis (Kottelat 2012, 2013), considering that there are no significant morphological differences between them, together with the fact that these four species are from Vietnam, they are unlikely to be conspecific (Bhoite et al. 2012). Thus, these four species were excluded from the diagnosis of the new species (Conway and Mayden 2010; Bhoite et al. 2012; Liu et al. 2012a). To date, no cave species have been discovered within the genus Balitora.
Link to full paper zookeys.pensoft.net/article/108545/
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Tao Luo, Zhi-Xia Chen, Xin-Rui Zhao, Jing Yu, Chang-Ting Lan, Jia-Jun Zhou, Ning Xiao, Jiang ZhouAbstractThis work describes a new species, Balitora anlongensis sp. nov., collected from a cave at Xinglong Town, Anlong County, Guzihou, China. Phylogenetic trees reconstructed based on two mitochondrial and three nuclear genes show that the new species represents an independent evolutionary lineage with large genetic differences, 7.1%–12.0% in mitochondrial gene cytochrome b and 9.2%–12.1% in cytochrome oxidase subunit 1, from congeners. Morphologically, the new species can be distinguished from the 18 species currently assigned to the genus Balitora by a combination of characters, most clearly by having two pairs of maxillary barbels; 8½ branched dorsal-fin rays; 5½ branched anal-fin rays; pectoral fin not reaching pelvic fin origin; dorsal-fin origin in front of pelvic fin origin; eye small (eye diameter approximately equal to outer maxillary barbel length); and fins lacking pigment in live fish. The new species represents the first record of Balitora inhabiting caves in China and increases the number of species in the genus Balitora in its present concept from 18 to 19. The study suggests that more evidence is needed to further clarify the taxonomic composition of the genus Balitora.
Key wordsNanpanjiang River, stone loach, taxonomy, phylogeny
IntroductionThe karst region of southwest China is well known as a distinctive center and hotspot of biodiversity (Myers et al. 2000). Distinctive karst habitats have created varied natural landscapes and organisms, such as cave river ecosystems and the organisms that inhabit them. Cavefishes are typical cave organisms (Niemiller et al. 2019). In China, there are approximately 170 endemic species of cavefishes belonging to two orders (Cypriniformes and Siluriformes) and four families (Cyprinidae, Nemacheilidae, Cobitidae, and Amblycipitidae) (Ma et al. 2019). In previous reports, cavefishes were mainly recorded in the Cyprinidae (83 species), Nemacheilidae (77 species), and Cobitidae (eight species) (Ma et al. 2019) (Suppl. material 1). New discoveries may be possible at the family, genus, and species level, considering that past surveys and reports of cavefishes have mainly focused on Guangxi and Yunnan provinces, China (Ma et al. 2019).
The genus Balitora, Gray, 1830 was established with Balitora brucei as the type species, originally placed in the Cobitidae (Gray, 1830), and is now placed within the Balitoridae (Fricke et al. 2023). Hemimyzon Regan, 1911 and Sinohomaloptera Fang, 1930, which are taxonomically closely related to Balitora, were established using H. formosanum and S. kwangsiensis, respectively, as the type species. The genus Balitora has long been the subject of taxonomic controversy, with different taxonomic schemes proposed based on morphological differences. Chen (1978) recognized one pair of maxillary barbels as a character that distinguishes Balitora from other genera. Later, several new Balitora species were reported, including B. pengi Huang, 1982, B. tchangi Zheng, 1982, B. nujiangensis Zhang & Zheng, 1983, and B. elongata Chen & Li, 1985 (Zheng et al. 1982; Zheng and Zhang 1983; Li and Chen 1985), which are currently placed in the genus Hemimyzon (Kottelat and Chu 1988). Kottelat and Chu (1988) and Kottelat (1988) reviewed the genus and considered Sinohomaloptera to be a synonym of Balitora as having one or two pairs of maxillary barbels. Based on three or more unbranched pelvic fin rays, B. pengi, B. tchangi, B. nujiangensis, and B. elongata were placed in Hemimyzon, while species with two branched pelvic fin rays were placed in Balitora, namely B. lancangjiangensis (Zheng, 1980), B. kwangsiensis (Fang, 1930), and B. longibarbata (Chen, 1982) (Kottelat and Chu 1988). Chen (1990) accepted this suggestion for a taxonomic revision of the species distributed in Yunnan. However, the suggestion of Kottelat and Chu (1988) was not adopted by Chinese scholars, and species were still placed in Balitora based on the number of maxillary barbel, and Sinohomaloptera was considered valid (Chen and Tang 2000; Jiang et al. 2016). Nevertheless, previous morphology-based studies have not resolved the phylogenetic relationships between Balitora, Hemimyzon and Sinohomaloptera due to a lack of molecular evidence.
Few molecular markers have been used to assess the phylogeny of the genus Balitora. A phylogenetic tree reconstructed by Šlechtová et al. (2007) based on the nuclear gene RAG1 showed that a species identified as Balitora sp. cf. burmanica showed that the genus Balitora is nested within the genus Homaloptera. The phylogeny of Liu et al. (2012a) based on mitochondrial (COI and ND4+ND5) and nuclear genes (RH1, RAG1, EGR2B, and IRBP), on the other hand, supports the view that Balitora (S. kwangsiensis) is close to Sinogastromyzon. Kumkar et al. (2016a) used two mitochondria (COI and Cyt b) to show for the first time phylogenetically that Balitora is not a monophyletic, but can be divided into three major clades. Keskar et al. (2018) then supported Balitora as a sister clade of Lepidocephalichthys based on mitochondrial COI and Cyt b. Tao et al. (2019) recovered Balitora (only B. elongata) as a sister clade of Sinohomaloptera (only S. kwangsiensis) based on a large-scale phylogeny of one mitochondrial and 14 nuclear genes. More recently, a phylogeny based on the mitochondrial genome (only B. ludongensis Liu & Chen, 2012) strongly support Balitora being close to ((Jinshaia + Lepturichthys) + Sinogastromyzon) (Shao et al. 2020). Based on the above various studies, it can be concluded that the phylogenetic position of the genus Balitora is unclear and may not be monophyletic.
To date, the classification of the genus remains controversial, mainly because of the lack of clear phylogenetic relationships and stable morphological characters among Balitora, Hemimyzon, and Sinohomaloptera (Table 1). In this study, we followed the latest taxonomic scheme after a comprehensive review, and Balitora was recorded with 19 species (Table 1), of which ten species are distributed in China, namely B. brucei Gray, 1830, B. burmanica Hora, 1932, B. elongata, B. kwangsiensis, B. lancangjiangensis, B. longibarbata, B. ludongensis, B. nantingensis Chen, Cui & Yang, 2005, B. meridionalis Kottelat, 1988, and B. tchangi (Liu et al. 2012b; Jiang et al. 2016) (Table 1). However, because this work did not have access to the original data for the four species (B. haithanhi, B. nigrocorpa, B. vanlani, and B. vanlongi) described by Nguyen (2005), as well as because B. haithanhi Nguyen, 2005, B. nigrocorpa Nguyen, 2005, and B. vanlani Nguyen, 2005 were used as synonyms of B. kwangsiensis and B. vanlongi was used as a synonym of B. lancangjiangensis (Kottelat 2012, 2013), considering that there are no significant morphological differences between them, together with the fact that these four species are from Vietnam, they are unlikely to be conspecific (Bhoite et al. 2012). Thus, these four species were excluded from the diagnosis of the new species (Conway and Mayden 2010; Bhoite et al. 2012; Liu et al. 2012a). To date, no cave species have been discovered within the genus Balitora.
Link to full paper zookeys.pensoft.net/article/108545/
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Phylogenomics and Morphology of the African Fish Genus Brycinus with Revalidation of Brachyalestes and Description of a New Species from the Congo Basin (Teleostei: Alestidae)
Melanie L. J. Stiassny, Cooper Keane, José J. M. M. Mbimbi, Bruno F. Melo
Author Affiliations +
Ichthyology & Herpetology, 111(4):597-611 (2023). https://doi.org/10.1643/i2023033
AbstractA time-calibrated phylogeny, based on nuclear ultraconserved elements and including representatives of all major alestid lineages, strongly supports two distantly related clades within the currently accepted concept of Brycinus. The first, which includes the type species of the genus, B. macrolepidotus (herein Brycinus), and a second, composed of taxa previously referred to as the B. nurse group (herein Brachyalestes), are both resolved as monophyletic. These results provide strong evidence for the restriction of the genus Brycinus to nine species, and for the revalidation of the genus Brachyalestes to accommodate 20 valid species. Within Brachyalestes, a new species from the Lulua River basin, initially misidentified as Brycinus kingsleyae, is described and resolved as sister to the widespread, central Congolese lowland species, Brachyalestes bimaculatus. Within Brachyalestes, a subclade mostly restricted to the Central Congo basin is estimated to have undergone diversification within the last 10 million years, suggesting that Late Neogene riverine reorganization likely influenced their allopatric speciation. The split of the new species, endemic to high elevation tributaries of the Lulua River, from its lowland sister species, Brachyalestes bimaculatus, suggests a Late Miocene/Early Pliocene colonization into the upland river ecosystems of the Katanga plateau in the southwestern Democratic Republic of Congo.
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Melanie L. J. Stiassny, Cooper Keane, José J. M. M. Mbimbi, Bruno F. Melo
Author Affiliations +
Ichthyology & Herpetology, 111(4):597-611 (2023). https://doi.org/10.1643/i2023033
AbstractA time-calibrated phylogeny, based on nuclear ultraconserved elements and including representatives of all major alestid lineages, strongly supports two distantly related clades within the currently accepted concept of Brycinus. The first, which includes the type species of the genus, B. macrolepidotus (herein Brycinus), and a second, composed of taxa previously referred to as the B. nurse group (herein Brachyalestes), are both resolved as monophyletic. These results provide strong evidence for the restriction of the genus Brycinus to nine species, and for the revalidation of the genus Brachyalestes to accommodate 20 valid species. Within Brachyalestes, a new species from the Lulua River basin, initially misidentified as Brycinus kingsleyae, is described and resolved as sister to the widespread, central Congolese lowland species, Brachyalestes bimaculatus. Within Brachyalestes, a subclade mostly restricted to the Central Congo basin is estimated to have undergone diversification within the last 10 million years, suggesting that Late Neogene riverine reorganization likely influenced their allopatric speciation. The split of the new species, endemic to high elevation tributaries of the Lulua River, from its lowland sister species, Brachyalestes bimaculatus, suggests a Late Miocene/Early Pliocene colonization into the upland river ecosystems of the Katanga plateau in the southwestern Democratic Republic of Congo.
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Two new remarkable and endangered catfish species of the genus Cambeva (Siluriformes, Trichomycteridae) from southern Brazil
Keywords: comparative morphology, mountain biodiversity, osteology, Rio Uruguai basinABSTRACTDuring a field inventory directed at trichomycterine habitats, two new species of the genus Cambeva, C. alphabelardense sp. nov. and C. betabelardense sp. nov., were found in the Rio Chapecó drainage, an area under high environmental decline due to intensive soya monoculture. These species share a peculiar head morphology and some unique osteological features, besides having a size that is smaller than in any other congener, being herein considered to be more closely related to each other than to other taxa. They differ from each other by several characters, including head shape, fin morphology, number of jaw teeth and opercular odontodes, and mesethmoid and metapterygoid shape. Furthermore, they were found in the same area, but in distinct biotopes, with one species found buried in the remnants of tree ferns and other plants on the stream bottom, restricted to a small residual fragment of the original forest, and the other species inhabiting a stream with gravel and small stones on the bottom. Field studies indicate that these species are threatened with extinction. Robust phylogenetic studies are still necessary to test relationship hypotheses involving the new taxa here described.
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- Wilson J.E.M. CostaLaboratory of Systematics and Evolution of Teleost Fishes, Institute of Biology, Federal University of Rio de Janeiro, Caixa Postal 68049, CEP 21941-971, Rio de Janeiro, Brazilhttps://orcid.org/0000-0002-0428-638X
- Caio R.M. FeltrinAv. Municipal, 45, Siderópolis, CEP 88860-000, Santa Catarina, Brazilhttps://orcid.org/0000-0002-1609-7295
- Axel M. KatzLaboratory of Systematics and Evolution of Teleost Fishes, Institute of Biology, Federal University of Rio de Janeiro, Caixa Postal 68049, CEP 21941-971, Rio de Janeiro, Brazilhttps://orcid.org/0000-0002-2933-7163
Keywords: comparative morphology, mountain biodiversity, osteology, Rio Uruguai basinABSTRACTDuring a field inventory directed at trichomycterine habitats, two new species of the genus Cambeva, C. alphabelardense sp. nov. and C. betabelardense sp. nov., were found in the Rio Chapecó drainage, an area under high environmental decline due to intensive soya monoculture. These species share a peculiar head morphology and some unique osteological features, besides having a size that is smaller than in any other congener, being herein considered to be more closely related to each other than to other taxa. They differ from each other by several characters, including head shape, fin morphology, number of jaw teeth and opercular odontodes, and mesethmoid and metapterygoid shape. Furthermore, they were found in the same area, but in distinct biotopes, with one species found buried in the remnants of tree ferns and other plants on the stream bottom, restricted to a small residual fragment of the original forest, and the other species inhabiting a stream with gravel and small stones on the bottom. Field studies indicate that these species are threatened with extinction. Robust phylogenetic studies are still necessary to test relationship hypotheses involving the new taxa here described.
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Triplophysa cehengensis, T. rongduensis, etc. • Four New hypogean Species of the Genus Triplophysa (Cypriniformes:, Nemacheilidae) from Guizhou Province, Southwest China, based on molecular and morphological data
Triplophysa cehengensis Luo, Mao, Zhao, Xiao & Zhou,
T. rongduensis Mao, Zhao, Yu, Xiao & Zhou,
T. panzhouensis Yu, Luo, Lan, Xiao & Zhou,
T. anlongensis Song, Luo, Lan, Zhao, Xiao & Zhou,
in Luo, Mao, Lan, Song, Zhao, Yu, Wang, Xiao, Zhou et Zhou, 2023.
DOI: 10.3897/zookeys.1185.105499
Abstract
Recently described cave species of the genus Triplophysa have been discovered in southwestern China, suggesting that the diversity of the genus is severely underestimated and that there may be many undescribed species. In this work, four new species of the genus Triplophysa are described from southwestern Guizhou Province, China, namely Triplophysa cehengensis Luo, Mao, Zhao, Xiao & Zhou, sp. nov. and Triplophysa rongduensis Mao, Zhao, Yu, Xiao & Zhou, sp. nov. from Rongdu Town, Ceheng County, Guizhou, Triplophysa panzhouensis Yu, Luo, Lan, Xiao & Zhou, sp. nov. from Hongguo Town, Panzhou City, Guizhou, and Triplophysa anlongensis Song, Luo, Lan, Zhao, Xiao & Zhou, sp. nov. from Xinglong Town, Anlong County, Guizhou. These four new species can be distinguished from all recognized congeners by a combination of morphological characteristics and significant genetic divergences. The discovery of these species increases the number of known cave species within the genus Triplophysa to 39, making the genus the second most diverse group of cave fishes in China after the golden-line fish genus Sinocyclocheilus. Based on the non-monophyletic relationships of the different watershed systems in the phylogenetic tree, this study also discusses the use of cave species of the genus Triplophysa to determine the possible historical connectivity of river systems.
Key words: Diversity, karst cave, morphology, new species, taxonomy, Triplophysa
Triplophysa cehengensis sp. nov. in life
A holotype GZNU20230214010 B paratype GZNU20230214011.
Triplophysa rongduensis sp. nov. in life, paratype GZNU20230106001
A left side view B right side view.
Triplophysa cehengensis Luo, Mao, Zhao, Xiao & Zhou, sp. nov.
Etymology: The specific epithet cehengensis is in reference to the type locality of the new species: Longjing Village, Rongdu Town, Ceheng County. We propose the common English name “Ceheng high-plateau loach” and the Chinese name “Cè Hēng Gāo Yuán Qīu (册亨高原鳅)”.
Triplophysa rongduensis Mao, Zhao, Yu, Xiao & Zhou, sp. nov.
Etymology: The specific epithet rongduensis is in reference to the type locality of the new species: Rongdu Town, Ceheng County, Guizhou Province, China. We propose the common English name “Rongdu high-plateau loach” and the Chinese name “Rǒng Dù Gāo Yuán Qīu (冗渡高原鳅).”
Triplophysa panzhouensis sp. nov. in life, paratype GZNU20230115001
A left side view B right side view.
Triplophysa anlongensis sp. nov. in life, paratype GZNU20230215022
A left side view B right side view.
Triplophysa panzhouensis Yu, Luo, Lan, Xiao & Zhou, sp. nov.
Etymology: The specific epithet panzhouensis is in reference to the type locality of the new species: Hongguo Town, Panzhou City, Guizhou Province, China. We propose the common English name “Panzhou high-plateau loach” and the Chinese name “Pán Zhõu Gāo Yuán Qīu (盘州高原鳅).”
Triplophysa anlongensis Lan, Song, Luo, Zhao, Xiao & Zhou, sp. nov.
Etymology: The specific epithet anlongensis is in reference to the type locality of the new species: NaNao Village, Xinglong Town, Anlong County, Guizhou Province, China. We propose the common English name “Anlong high-plateau loach” and the Chinese name “ān lóng Gāo Yuán Qīu (安龙高原鳅).”
Tao Luo, Ming-Le Mao, Chang-Ting Lan, Ling-Xing Song, Xin-Rui Zhao, Jing Yu, Xing-Liang Wang, Ning Xiao, Jia-Jun Zhou and Jiang Zhou. 2023. Four New hypogean Species of the Genus Triplophysa (Osteichthyes, Cypriniformes, Nemacheilidae) from Guizhou Province, Southwest China, based on molecular and morphological data. ZooKeys. 1185: 43-81. DOI: 10.3897/zookeys.1185.105499
Triplophysa cehengensis Luo, Mao, Zhao, Xiao & Zhou,
T. rongduensis Mao, Zhao, Yu, Xiao & Zhou,
T. panzhouensis Yu, Luo, Lan, Xiao & Zhou,
T. anlongensis Song, Luo, Lan, Zhao, Xiao & Zhou,
in Luo, Mao, Lan, Song, Zhao, Yu, Wang, Xiao, Zhou et Zhou, 2023.
DOI: 10.3897/zookeys.1185.105499
Abstract
Recently described cave species of the genus Triplophysa have been discovered in southwestern China, suggesting that the diversity of the genus is severely underestimated and that there may be many undescribed species. In this work, four new species of the genus Triplophysa are described from southwestern Guizhou Province, China, namely Triplophysa cehengensis Luo, Mao, Zhao, Xiao & Zhou, sp. nov. and Triplophysa rongduensis Mao, Zhao, Yu, Xiao & Zhou, sp. nov. from Rongdu Town, Ceheng County, Guizhou, Triplophysa panzhouensis Yu, Luo, Lan, Xiao & Zhou, sp. nov. from Hongguo Town, Panzhou City, Guizhou, and Triplophysa anlongensis Song, Luo, Lan, Zhao, Xiao & Zhou, sp. nov. from Xinglong Town, Anlong County, Guizhou. These four new species can be distinguished from all recognized congeners by a combination of morphological characteristics and significant genetic divergences. The discovery of these species increases the number of known cave species within the genus Triplophysa to 39, making the genus the second most diverse group of cave fishes in China after the golden-line fish genus Sinocyclocheilus. Based on the non-monophyletic relationships of the different watershed systems in the phylogenetic tree, this study also discusses the use of cave species of the genus Triplophysa to determine the possible historical connectivity of river systems.
Key words: Diversity, karst cave, morphology, new species, taxonomy, Triplophysa
Triplophysa cehengensis sp. nov. in life
A holotype GZNU20230214010 B paratype GZNU20230214011.
Triplophysa rongduensis sp. nov. in life, paratype GZNU20230106001
A left side view B right side view.
Triplophysa cehengensis Luo, Mao, Zhao, Xiao & Zhou, sp. nov.
Etymology: The specific epithet cehengensis is in reference to the type locality of the new species: Longjing Village, Rongdu Town, Ceheng County. We propose the common English name “Ceheng high-plateau loach” and the Chinese name “Cè Hēng Gāo Yuán Qīu (册亨高原鳅)”.
Triplophysa rongduensis Mao, Zhao, Yu, Xiao & Zhou, sp. nov.
Etymology: The specific epithet rongduensis is in reference to the type locality of the new species: Rongdu Town, Ceheng County, Guizhou Province, China. We propose the common English name “Rongdu high-plateau loach” and the Chinese name “Rǒng Dù Gāo Yuán Qīu (冗渡高原鳅).”
Triplophysa panzhouensis sp. nov. in life, paratype GZNU20230115001
A left side view B right side view.
Triplophysa anlongensis sp. nov. in life, paratype GZNU20230215022
A left side view B right side view.
Triplophysa panzhouensis Yu, Luo, Lan, Xiao & Zhou, sp. nov.
Etymology: The specific epithet panzhouensis is in reference to the type locality of the new species: Hongguo Town, Panzhou City, Guizhou Province, China. We propose the common English name “Panzhou high-plateau loach” and the Chinese name “Pán Zhõu Gāo Yuán Qīu (盘州高原鳅).”
Triplophysa anlongensis Lan, Song, Luo, Zhao, Xiao & Zhou, sp. nov.
Etymology: The specific epithet anlongensis is in reference to the type locality of the new species: NaNao Village, Xinglong Town, Anlong County, Guizhou Province, China. We propose the common English name “Anlong high-plateau loach” and the Chinese name “ān lóng Gāo Yuán Qīu (安龙高原鳅).”
Tao Luo, Ming-Le Mao, Chang-Ting Lan, Ling-Xing Song, Xin-Rui Zhao, Jing Yu, Xing-Liang Wang, Ning Xiao, Jia-Jun Zhou and Jiang Zhou. 2023. Four New hypogean Species of the Genus Triplophysa (Osteichthyes, Cypriniformes, Nemacheilidae) from Guizhou Province, Southwest China, based on molecular and morphological data. ZooKeys. 1185: 43-81. DOI: 10.3897/zookeys.1185.105499
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A new subtropical species of goby of the genus Luciogobius (Gobiidae) from southwestern JapanPISCESACTINOPTERYGIITELEOSTEINANSEI ISLANDSOSUMI LINEAbstractLuciogobius griseus n. sp., belonging to the Luciogobius platycephalus complex, is described on the basis of 40 specimens from the Nansei Islands, southwestern Japan (subtropical area). The new species is generally found in intertidal gravel sediments subjected to freshwater runoff from springs on coastal lines or river mouths and is characterized by the following combination of characters: total second dorsal-fin rays 9–12 (modally 11); total anal-fin rays usually 12–14 (modally 13); pectoral-fin rays 12–15 (modally 13); vertebrae 17 or 18 + 23 or 24 = 40–42 (18 + 23 = 41); uppermost 2–4 (2–3) rays on pectoral fin free; 8–12 pectoral-fin rays branched (uppermost free rays and sometimes lowermost ray unbranched); pectoral-fin membrane not strongly concave anteriorly (except for free rays); pelvic fins united, forming a disk; head relatively short, 13.9–20.8% of standard length (SL); relatively short pre-pelvic fin, length 14.4–22.1% of SL; relatively long pre-dorsal fin, length 68.9–72.9% of SL; relatively long pre-anal fin, length 63.5–67.7% of SL; relatively short pelvic fin, length 2.8–4.7% of SL; distance between posterior end of pelvic fin and anus relatively long, 32.0–36.4% of SL (aforementioned morphometrics each distinguishing L. griseus n. sp. from other species in the L. platycephalus complex); and fresh specimens with greenish dark brown or gray body. A key to the L. platycephalus complex is provided, together with limited descriptions and remarks on the other two members of the complex.
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Phylogenomics of the narrowly endemic Eurycheilichthys (Siluriformes: Loricariidae): Sympatric Species with Non-sister Relationships suggest mainly Allopatric Speciation
Armored catfishes of the genus Eurycheilichthys
in Delapieve, Rocha & Reis, 2023.
DOI: 10.1016/j.ympev.2023.107970
Highlights
• Phylogenomic inference for Eurycheilichthys based on ddRAD sequence data.
• Monophyly of most, but not all, morphospecies corroborated by genome-wide data.
• Most sympatric species are not sister lineages, suggesting allopatric diversification and secondary contact.
• Higher diversity among lineages in the Taquari-Antas basin indicates a more dynamic landscape.
• Eastern clade species should be target by future studies to assess the presence of cryptic species or hybridization.
Abstract
Armored catfishes of the genus Eurycheilichthys are endemic to Southern Brazil and Misiones (Argentina) comprising nine species of small size, with a high degree of sympatry and species diversity distributed in two river basins. Here we use new genome-wide data to infer a species phylogeny and test species boundaries for this poorly known group. We estimate 1) the phylogenetic relationships of the species of Eurycheilichthys based on 29,350 loci in 65 individuals of nine species plus outgroups, and 2) the population structure and differentiation based on 43,712 loci and 62 individuals to estimate how geography may have acted on speciation and formation of the sympatric species groups. Analyses support the monophyly of the genus and suggest two species-inclusive clades (East and West) with high support and very recently diverged species. Western clade contains E. limulus (from upper Jacuí River basin) that is sister to Western species of the Taquari-Antas basin plus E. paucidens. The Eastern clade contains E. pantherinus (from Uruguay River basin) sister to the Eastern species of the Taquari-Antas basin E. coryphaenus, plus the central-distributed species E. planus and E. vacariensis, and the more widely-distributed species E. luisae. Eurycheilichthys luisae is not monophyletic and may contain one or more cryptic species or hybrid individuals. A stronger diversity on structure of lineages on the Taquari-Antas, when compared to upper Uruguay and Jacuí River basins, and the fact that most of the sympatrically distributed taxa have non-sister relationships suggest a scenario of mainly allopatric speciation and may indicate a more dynamic landscape with headwater capture events among these tributaries.
Keywords: Neotropics, Biodiversity, Cascudinhos, ddRADseq, Phylogenetics
Maria Laura S. Delapieve, Luiz A. Rocha and Roberto E. Reis. 2023. Phylogenomics of the narrowly endemic Eurycheilichthys (Siluriformes: Loricariidae): Sympatric Species with Non-sister Relationships suggest mainly Allopatric Speciation. Molecular Phylogenetics and Evolution. 190, 107970. DOI: 10.1016/j.ympev.2023.107970
==========================
Armored catfishes of the genus Eurycheilichthys
in Delapieve, Rocha & Reis, 2023.
DOI: 10.1016/j.ympev.2023.107970
Highlights
• Phylogenomic inference for Eurycheilichthys based on ddRAD sequence data.
• Monophyly of most, but not all, morphospecies corroborated by genome-wide data.
• Most sympatric species are not sister lineages, suggesting allopatric diversification and secondary contact.
• Higher diversity among lineages in the Taquari-Antas basin indicates a more dynamic landscape.
• Eastern clade species should be target by future studies to assess the presence of cryptic species or hybridization.
Abstract
Armored catfishes of the genus Eurycheilichthys are endemic to Southern Brazil and Misiones (Argentina) comprising nine species of small size, with a high degree of sympatry and species diversity distributed in two river basins. Here we use new genome-wide data to infer a species phylogeny and test species boundaries for this poorly known group. We estimate 1) the phylogenetic relationships of the species of Eurycheilichthys based on 29,350 loci in 65 individuals of nine species plus outgroups, and 2) the population structure and differentiation based on 43,712 loci and 62 individuals to estimate how geography may have acted on speciation and formation of the sympatric species groups. Analyses support the monophyly of the genus and suggest two species-inclusive clades (East and West) with high support and very recently diverged species. Western clade contains E. limulus (from upper Jacuí River basin) that is sister to Western species of the Taquari-Antas basin plus E. paucidens. The Eastern clade contains E. pantherinus (from Uruguay River basin) sister to the Eastern species of the Taquari-Antas basin E. coryphaenus, plus the central-distributed species E. planus and E. vacariensis, and the more widely-distributed species E. luisae. Eurycheilichthys luisae is not monophyletic and may contain one or more cryptic species or hybrid individuals. A stronger diversity on structure of lineages on the Taquari-Antas, when compared to upper Uruguay and Jacuí River basins, and the fact that most of the sympatrically distributed taxa have non-sister relationships suggest a scenario of mainly allopatric speciation and may indicate a more dynamic landscape with headwater capture events among these tributaries.
Keywords: Neotropics, Biodiversity, Cascudinhos, ddRADseq, Phylogenetics
Maria Laura S. Delapieve, Luiz A. Rocha and Roberto E. Reis. 2023. Phylogenomics of the narrowly endemic Eurycheilichthys (Siluriformes: Loricariidae): Sympatric Species with Non-sister Relationships suggest mainly Allopatric Speciation. Molecular Phylogenetics and Evolution. 190, 107970. DOI: 10.1016/j.ympev.2023.107970
==========================
Ophichthus naevius • A New Snake Eel Species of the Genus Ophichthus (Anguilliformes: Ophichthidae) from the southeast Coast of India, Bay of Bengal with Taxonomic Account of Ophichthus chilkensis
Ophichthus naevius
Kodeeswaran, Kathirvelpandian, Mohapatra, Thangappan Kumar & Sarkar, 2023
DOI: 10.1111/jfb.15617
twitter.com/ParamasivamKod1
Abstract
A new species of the ophichthid eel of the family Ophichthidae is described based on five specimens collected from the Mudasalodai fish landing centre, Off Cuddalore coast, southeast coast of India, Bay of Bengal. Ophichthus naevius sp. nov. is distinguished from its congeners by having a unique colour pattern: dorsal body with dense of numerous dark spots or patches, ventral body pale yellowish green, dorsal fin origin just before pectoral fin tip, vertebral formula: 12–14/52–53/134–138, teeth on jaw uniserial and pointed. The study also reports the range extension and molecular evidence of Ophichthus chilkensis from south India. Molecular analyses were done for both species and their phylogenetic relationship suggests that the new species exhibit 10.2% genetic divergence with its' congener, O. sangjuensis followed by O. brevicaudatus (10.4%), and Ophichthus sp.1 (11.8%) also forms closest clade in both BI and ML Tree. Similarly, according to the topology of ML tree, the species O. chilkensis forms clade with Ophichthus sp. 5, O. remiger, O. frontalis, Ophichthus sp. 6 and O. rex. and suggests that would be the genetically closest congener.
Keywords: Molecular analyses, new species, Taxonomy
Ophichthus naevius sp. nov.
Paramasivam Kodeeswaran, Ayyathurai Kathirvelpandian, Anil Mohapatra, Thipramalai Thangappan Pillai Ajith Kumar and Uttam Kumar Sarkar. 2023. A New Snake Eel Species of the Genus Ophichthus (Anguilliformes: Ophichthidae) from the southeast Coast of India, Bay of Bengal with Taxonomic Account of Ophichthus chilkensis. Journal of Fish Biology. DOI: 10.1111/jfb.15617
twitter.com/ParamasivamKod1/status/1725420202308112754
==========================
Ophichthus naevius
Kodeeswaran, Kathirvelpandian, Mohapatra, Thangappan Kumar & Sarkar, 2023
DOI: 10.1111/jfb.15617
twitter.com/ParamasivamKod1
Abstract
A new species of the ophichthid eel of the family Ophichthidae is described based on five specimens collected from the Mudasalodai fish landing centre, Off Cuddalore coast, southeast coast of India, Bay of Bengal. Ophichthus naevius sp. nov. is distinguished from its congeners by having a unique colour pattern: dorsal body with dense of numerous dark spots or patches, ventral body pale yellowish green, dorsal fin origin just before pectoral fin tip, vertebral formula: 12–14/52–53/134–138, teeth on jaw uniserial and pointed. The study also reports the range extension and molecular evidence of Ophichthus chilkensis from south India. Molecular analyses were done for both species and their phylogenetic relationship suggests that the new species exhibit 10.2% genetic divergence with its' congener, O. sangjuensis followed by O. brevicaudatus (10.4%), and Ophichthus sp.1 (11.8%) also forms closest clade in both BI and ML Tree. Similarly, according to the topology of ML tree, the species O. chilkensis forms clade with Ophichthus sp. 5, O. remiger, O. frontalis, Ophichthus sp. 6 and O. rex. and suggests that would be the genetically closest congener.
Keywords: Molecular analyses, new species, Taxonomy
Ophichthus naevius sp. nov.
Paramasivam Kodeeswaran, Ayyathurai Kathirvelpandian, Anil Mohapatra, Thipramalai Thangappan Pillai Ajith Kumar and Uttam Kumar Sarkar. 2023. A New Snake Eel Species of the Genus Ophichthus (Anguilliformes: Ophichthidae) from the southeast Coast of India, Bay of Bengal with Taxonomic Account of Ophichthus chilkensis. Journal of Fish Biology. DOI: 10.1111/jfb.15617
twitter.com/ParamasivamKod1/status/1725420202308112754
==========================
Balitora anlongensis • the First Cavefish Species of the Genus Balitora (Cypriniformes: Balitoridae) from Guizhou Province, southwest China
Balitora anlongensis Luo, Chen, Zhao, Yu, Lan & Zhou,
in Luo, Chen, Zhao, Yu, Lan, Zhou, Xiao et Zhou, 2023.
DOI: 10.3897/zookeys.1185.108545
Abstract
This work describes a new species, Balitora anlongensis sp. nov., collected from a cave at Xinglong Town, Anlong County, Guzihou, China. Phylogenetic trees reconstructed based on two mitochondrial and three nuclear genes show that the new species represents an independent evolutionary lineage with large genetic differences, 7.1%–12.0% in mitochondrial gene cytochrome b and 9.2%–12.1% in cytochrome oxidase subunit 1, from congeners. Morphologically, the new species can be distinguished from the 18 species currently assigned to the genus Balitora by a combination of characters, most clearly by having two pairs of maxillary barbels; 8½ branched dorsal-fin rays; 5½ branched anal-fin rays; pectoral fin not reaching pelvic fin origin; dorsal-fin origin in front of pelvic fin origin; eye small (eye diameter approximately equal to outer maxillary barbel length); and fins lacking pigment in live fish. The new species represents the first record of Balitora inhabiting caves in China and increases the number of species in the genus Balitora in its present concept from 18 to 19. The study suggests that more evidence is needed to further clarify the taxonomic composition of the genus Balitora.
Key words: Nanpanjiang River, stone loach, taxonomy, phylogeny
Morphological characters of holotype GZNU20230215007 of Balitora anlongensis sp. nov. in preservative (10% formalin)
A lateral view B dorsal view C ventral view D ventral side view of head, and E dorsal side view of head. Photos from Tao Luo. Abbreviations: M, maxillary barbels; AN, anterior nostril.
Balitora anlongensis sp. nov. in life, paratypes GZNU20230106001 (photos A and B) and GZNU20230215014 (photo C)
A right-side view B ventral side view, and C dorsal view.
Photographs A, B were shot indoors at ~ 9:00 p.m. Photo C was taken in the cave at ~ 15:00 noon.
Balitora anlongensis Luo, Chen, Zhao, Yu, Lan & Zhou, sp. nov.
Diagnosis: Balitora anlongensis sp. nov. can be distinguished from other congeners by the following combination of characters: (1) two pairs of maxillary barbels; (2) dorsal fin rays iii, 8½; (3) pectoral fin viii, 11; (4) pelvic fin rays ii, 9; (5) anal fin rays iii, 5½; (6) lateral-line scales 66–68; (7) tip of pectoral fin not reaching to the pelvic fin origin; (8) dorsal fin origin anterior to the pelvic fin origin; (9) tip of the pelvic fin reaching to the anus; (10) eyes small, eye diameter equal to outer maxillary barbel length; (11) six to seven indistinctly separated transversely oval blotches on the dorsal side; and (12) each fin transparent and unpigmented in life.
Etymology: The specific epithet “anlongensis” is in reference to the type locality of the new species: NaNao Village, Xinglong Town, Anlong County, Guizhou Province, China. We propose the common English name “Anlong stone loach” and the Chinese name “ān lóng Pá Qīu (安龙爬鳅)”.
Tao Luo, Zhi-Xia Chen, Xin-Rui Zhao, Jing Yu, Chang-Ting Lan, Jia-Jun Zhou, Ning Xiao and Jiang Zhou. 2023. Balitora anlongensis, the First Cavefish Species of the Genus Balitora (Teleostei, Balitoridae) from Guizhou Province, southwest China. ZooKeys. 1185: 21-42. DOI: 10.3897/zookeys.1185.108545
==========================
Balitora anlongensis Luo, Chen, Zhao, Yu, Lan & Zhou,
in Luo, Chen, Zhao, Yu, Lan, Zhou, Xiao et Zhou, 2023.
DOI: 10.3897/zookeys.1185.108545
Abstract
This work describes a new species, Balitora anlongensis sp. nov., collected from a cave at Xinglong Town, Anlong County, Guzihou, China. Phylogenetic trees reconstructed based on two mitochondrial and three nuclear genes show that the new species represents an independent evolutionary lineage with large genetic differences, 7.1%–12.0% in mitochondrial gene cytochrome b and 9.2%–12.1% in cytochrome oxidase subunit 1, from congeners. Morphologically, the new species can be distinguished from the 18 species currently assigned to the genus Balitora by a combination of characters, most clearly by having two pairs of maxillary barbels; 8½ branched dorsal-fin rays; 5½ branched anal-fin rays; pectoral fin not reaching pelvic fin origin; dorsal-fin origin in front of pelvic fin origin; eye small (eye diameter approximately equal to outer maxillary barbel length); and fins lacking pigment in live fish. The new species represents the first record of Balitora inhabiting caves in China and increases the number of species in the genus Balitora in its present concept from 18 to 19. The study suggests that more evidence is needed to further clarify the taxonomic composition of the genus Balitora.
Key words: Nanpanjiang River, stone loach, taxonomy, phylogeny
Morphological characters of holotype GZNU20230215007 of Balitora anlongensis sp. nov. in preservative (10% formalin)
A lateral view B dorsal view C ventral view D ventral side view of head, and E dorsal side view of head. Photos from Tao Luo. Abbreviations: M, maxillary barbels; AN, anterior nostril.
Balitora anlongensis sp. nov. in life, paratypes GZNU20230106001 (photos A and B) and GZNU20230215014 (photo C)
A right-side view B ventral side view, and C dorsal view.
Photographs A, B were shot indoors at ~ 9:00 p.m. Photo C was taken in the cave at ~ 15:00 noon.
Balitora anlongensis Luo, Chen, Zhao, Yu, Lan & Zhou, sp. nov.
Diagnosis: Balitora anlongensis sp. nov. can be distinguished from other congeners by the following combination of characters: (1) two pairs of maxillary barbels; (2) dorsal fin rays iii, 8½; (3) pectoral fin viii, 11; (4) pelvic fin rays ii, 9; (5) anal fin rays iii, 5½; (6) lateral-line scales 66–68; (7) tip of pectoral fin not reaching to the pelvic fin origin; (8) dorsal fin origin anterior to the pelvic fin origin; (9) tip of the pelvic fin reaching to the anus; (10) eyes small, eye diameter equal to outer maxillary barbel length; (11) six to seven indistinctly separated transversely oval blotches on the dorsal side; and (12) each fin transparent and unpigmented in life.
Etymology: The specific epithet “anlongensis” is in reference to the type locality of the new species: NaNao Village, Xinglong Town, Anlong County, Guizhou Province, China. We propose the common English name “Anlong stone loach” and the Chinese name “ān lóng Pá Qīu (安龙爬鳅)”.
Tao Luo, Zhi-Xia Chen, Xin-Rui Zhao, Jing Yu, Chang-Ting Lan, Jia-Jun Zhou, Ning Xiao and Jiang Zhou. 2023. Balitora anlongensis, the First Cavefish Species of the Genus Balitora (Teleostei, Balitoridae) from Guizhou Province, southwest China. ZooKeys. 1185: 21-42. DOI: 10.3897/zookeys.1185.108545
==========================
Hyphessobrycon cantoi • A New Hyphessobrycon (Characiformes: Characidae) of the Hyphessobrycon heterorhabdus species-group from the lower Amazon Basin, Brazil
Hyphessobrycon cantoi
Faria, Guimarães, Rodrigues, Oliveira & Lima, 2021
DOI: 10.1590/1982-0224-2020-0102
ABSTRACT
A new species of Hyphessobrycon belonging to the Hyphessobrycon heterorhabdus species-group from the lower rio Tapajós, state of Pará, Brazil, is described. The new species is allocated into the Hyphessobrycon heterorhabdus species-group due to its color pattern, composed by an anteriorly well-defined, horizontally elongated humeral blotch that becomes diffuse and blurred posteriorly, where it overlaps with a conspicuous midlateral dark stripe that becomes blurred towards the caudal peduncle and the presence, in living specimens, of a tricolored longitudinal pattern composed by a dorsal red or reddish longitudinal stripe, a middle iridescent, golden or silvery longitudinal stripe, and a more ventrally-lying longitudinal dark pattern composed by the humeral blotch and dark midlateral stripe. It can be distinguished from all other species of the group by possessing humeral blotch with a straight or slightly rounded ventral profile, lacking a ventral expansion present in all other species of the group. The new species is also distinguished from Hyphessobrycon heterorhabdus by a 9.6% genetic distance in the cytochrome c oxidase I gene. The little morphological distinction of the new species when compared with its most similar congener, H. heterorhabdus, indicates that the new species is one of the first truly cryptic fish species described from the Amazon basin.
Keywords: Biodiversity; Cryptic Species; DNA Barcoding; Rio Amazonas; Rio Tapajós.
Hyphessobrycon cantoi.
Living specimen, Brazil, Pará, Santarém, stream tributary of lago Maicá (not preserved).
Hyphessobrycon cantoi, new species
Diagnosis. Hyphessobrycon cantoi can be distinguished from all congeners, except H. amapaensis, H. ericae, H. heterorhabdus, H. sateremawe and H. wosiackii, by the presence of an elongated, anteriorly well-defined humeral blotch that becomes progressively diffuse and blurred posteriorly, overlapping with a midlateral dark stripe. Hyphessobrycon cantoi can be distinguished from H. ericae and H. wosiackii by lacking a caudal peduncle blotch (vs. presence of a caudal peduncle blotch). Hyphessobrycon cantoi can be distinguished from H. amapaensis, H. heterorhabdus and H. sateremawe by lacking a ventral extension of the humeral blotch (vs. ventral extension of the humeral blotch present, although absence of ventral extension may occurs in specimens of H. amapaensis). Hyphessobrycon cantoi can be further distinguished from H. amapaensis by presenting a conspicuous midlateral dark stripe (vs. inconspicuous midlateral dark stripe) and by possessing a relatively thin red longitudinal stripe (vs. midlateral red stripe very thick and conspicuous). Hyphessobrycon cantoi can be also further distinguished from H. sateremawe by presenting a humeral blotch narrower, occupying vertical height equivalent to less than one scale row to middle of body (vs. humeral blotch and continuous midlateral stripe broad, occupying vertical height equivalent of two scale rows to middle of body). Hyphessobrycon cantoi is also distinguished from H. heterorhabdus by >9% of genetic distance in the cytochrome c oxidase I (COI) gene. Hyphessobrycon cantoi can be distinguished from H. heterorhabdus by 53-79 mutations and from H. ericae by 87 mutations in the COI gene (S3).
Etymology. The specific name is a homage to André Luiz C. Canto, curator of the fish collection of the Universidade Federal do Oeste do Pará (UFOPA), in recognition of his contribution to the knowledge of the fishes from the rio Tapajós basin. A genitive noun.
Tiago C. Faria, Karen L. A. Guimarães, Luís R. R. Rodrigues, Claudio Oliveira and Flávio C.T. Lima. 2021. A New Hyphessobrycon (Characiformes: Characidae) of the Hyphessobrycon heterorhabdus species-group from the lower Amazon Basin, Brazil. Neotrop. ichthyol. 19(1); DOI: 10.1590/1982-0224-2020-0102
==========================
Hyphessobrycon cantoi
Faria, Guimarães, Rodrigues, Oliveira & Lima, 2021
DOI: 10.1590/1982-0224-2020-0102
ABSTRACT
A new species of Hyphessobrycon belonging to the Hyphessobrycon heterorhabdus species-group from the lower rio Tapajós, state of Pará, Brazil, is described. The new species is allocated into the Hyphessobrycon heterorhabdus species-group due to its color pattern, composed by an anteriorly well-defined, horizontally elongated humeral blotch that becomes diffuse and blurred posteriorly, where it overlaps with a conspicuous midlateral dark stripe that becomes blurred towards the caudal peduncle and the presence, in living specimens, of a tricolored longitudinal pattern composed by a dorsal red or reddish longitudinal stripe, a middle iridescent, golden or silvery longitudinal stripe, and a more ventrally-lying longitudinal dark pattern composed by the humeral blotch and dark midlateral stripe. It can be distinguished from all other species of the group by possessing humeral blotch with a straight or slightly rounded ventral profile, lacking a ventral expansion present in all other species of the group. The new species is also distinguished from Hyphessobrycon heterorhabdus by a 9.6% genetic distance in the cytochrome c oxidase I gene. The little morphological distinction of the new species when compared with its most similar congener, H. heterorhabdus, indicates that the new species is one of the first truly cryptic fish species described from the Amazon basin.
Keywords: Biodiversity; Cryptic Species; DNA Barcoding; Rio Amazonas; Rio Tapajós.
Hyphessobrycon cantoi.
Living specimen, Brazil, Pará, Santarém, stream tributary of lago Maicá (not preserved).
Hyphessobrycon cantoi, new species
Diagnosis. Hyphessobrycon cantoi can be distinguished from all congeners, except H. amapaensis, H. ericae, H. heterorhabdus, H. sateremawe and H. wosiackii, by the presence of an elongated, anteriorly well-defined humeral blotch that becomes progressively diffuse and blurred posteriorly, overlapping with a midlateral dark stripe. Hyphessobrycon cantoi can be distinguished from H. ericae and H. wosiackii by lacking a caudal peduncle blotch (vs. presence of a caudal peduncle blotch). Hyphessobrycon cantoi can be distinguished from H. amapaensis, H. heterorhabdus and H. sateremawe by lacking a ventral extension of the humeral blotch (vs. ventral extension of the humeral blotch present, although absence of ventral extension may occurs in specimens of H. amapaensis). Hyphessobrycon cantoi can be further distinguished from H. amapaensis by presenting a conspicuous midlateral dark stripe (vs. inconspicuous midlateral dark stripe) and by possessing a relatively thin red longitudinal stripe (vs. midlateral red stripe very thick and conspicuous). Hyphessobrycon cantoi can be also further distinguished from H. sateremawe by presenting a humeral blotch narrower, occupying vertical height equivalent to less than one scale row to middle of body (vs. humeral blotch and continuous midlateral stripe broad, occupying vertical height equivalent of two scale rows to middle of body). Hyphessobrycon cantoi is also distinguished from H. heterorhabdus by >9% of genetic distance in the cytochrome c oxidase I (COI) gene. Hyphessobrycon cantoi can be distinguished from H. heterorhabdus by 53-79 mutations and from H. ericae by 87 mutations in the COI gene (S3).
Etymology. The specific name is a homage to André Luiz C. Canto, curator of the fish collection of the Universidade Federal do Oeste do Pará (UFOPA), in recognition of his contribution to the knowledge of the fishes from the rio Tapajós basin. A genitive noun.
Tiago C. Faria, Karen L. A. Guimarães, Luís R. R. Rodrigues, Claudio Oliveira and Flávio C.T. Lima. 2021. A New Hyphessobrycon (Characiformes: Characidae) of the Hyphessobrycon heterorhabdus species-group from the lower Amazon Basin, Brazil. Neotrop. ichthyol. 19(1); DOI: 10.1590/1982-0224-2020-0102
==========================
Amblyceps crassioris • A New sisoroid Catfish (Siluriformes: Amblycipitidae) from Odisha, India
Amblyceps crassioris
Vijayakrishnan & Jayasimhan, 2023
DOI: 10.1111/jfb.15599
facebook.com/Meenkaran
Abstract
Amblyceps crassioris, a new species of amblycipitid catfish, is described from the Mahanadi River basin in Odisha, India. The new species can be distinguished from its congeners in having a combination of the following characters: a deeply forked caudal fin, centrally projecting hooks on proximal lepidotrichia of median caudal-fin rays absent, jaws equal in length, lateral line absent, body depth at anus 15.1%–19.5% standard length (SL), caudal peduncle depth 13.0%–18.3% SL, adipose-fin base length 21.1%–27.1% SL, eye diameter 7.35%–14.1% head length and 38 total vertebrae.
Keywords: biogeography, cryptic diversity, Eastern Ghats, Mahanadi River, Sisoroidea
Cleared and stained caudal fin of Amblyceps sp.
(a) Amblyceps crassioris, paratype, showing absence of centrally projecting hooks (b) Amblyceps tenuisipinis showing poorly formed centrally projecting hooks and (c) Amblyceps arunachalense (Photo Credit : Achom Darshan) showing well-developed hooks on the proximal lepidotrichia of median caudal-fin rays.
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Amblyceps crassioris, a new species
Amblyceps crassioris habitat
photo by Abhisek Mishra
Balaji Vijayakrishnan and Praveenraj Jayasimhan. 2023. Amblyceps crassioris, A New sisoroid Catfish from Odisha, India (Siluriformes: Amblycipitidae). Journal of Fish Biology. DOI: 10.1111/jfb.15599
facebook.com/Meenkaran/posts/781103777364380
twitter.com/Meenkaran1/status/1727359672242590204
==========================
Amblyceps crassioris
Vijayakrishnan & Jayasimhan, 2023
DOI: 10.1111/jfb.15599
facebook.com/Meenkaran
Abstract
Amblyceps crassioris, a new species of amblycipitid catfish, is described from the Mahanadi River basin in Odisha, India. The new species can be distinguished from its congeners in having a combination of the following characters: a deeply forked caudal fin, centrally projecting hooks on proximal lepidotrichia of median caudal-fin rays absent, jaws equal in length, lateral line absent, body depth at anus 15.1%–19.5% standard length (SL), caudal peduncle depth 13.0%–18.3% SL, adipose-fin base length 21.1%–27.1% SL, eye diameter 7.35%–14.1% head length and 38 total vertebrae.
Keywords: biogeography, cryptic diversity, Eastern Ghats, Mahanadi River, Sisoroidea
Cleared and stained caudal fin of Amblyceps sp.
(a) Amblyceps crassioris, paratype, showing absence of centrally projecting hooks (b) Amblyceps tenuisipinis showing poorly formed centrally projecting hooks and (c) Amblyceps arunachalense (Photo Credit : Achom Darshan) showing well-developed hooks on the proximal lepidotrichia of median caudal-fin rays.
facebook.com/Meenkaran
Amblyceps crassioris, a new species
Amblyceps crassioris habitat
photo by Abhisek Mishra
Balaji Vijayakrishnan and Praveenraj Jayasimhan. 2023. Amblyceps crassioris, A New sisoroid Catfish from Odisha, India (Siluriformes: Amblycipitidae). Journal of Fish Biology. DOI: 10.1111/jfb.15599
facebook.com/Meenkaran/posts/781103777364380
twitter.com/Meenkaran1/status/1727359672242590204
==========================
Resolving Phylogenetic Relationships and Taxonomic Revision in the Pseudogastromyzon Genus (Cypriniformes: Gastromyzonidae): Molecular and Morphological Evidence for A New Genus, Labigastromyzon
in J. Chen, Y. Chen, Tang, Lei, Yan et Song, 2023.
DOI: 10.1111/1749-4877.12761
Researchgate.net/publication/373874401
Abstract
The Pseudogastromyzon genus, consisting of species predominantly distributed throughout southeastern China, has garnered increasing market attention in recent years due to its ornamental appeal. However, the overlapping diagnostic attributes render the commonly accepted criteria for interspecific identification unreliable, leaving the phylogenetic relationships among Pseudogastromyzon species unexplored. In the present study, we undertake molecular phylogenetic and morphological examinations of the Pseudogastromyzon genus. Our phylogenetic analysis of mitochondrial genes distinctly segregated Pseudogastromyzon species into two clades: the Pseudogastromyzon clade and the Labigastromyzon clade. A subsequent morphological assessment revealed that the primary dermal ridge (specifically, the second ridge) within the labial adhesive apparatus serves as an effective and precise interspecific diagnostic characteristic. Moreover, the distributional ranges of Pseudogastromyzon and Labigastromyzon are markedly distinct, exhibiting only a narrow area of overlap. Considering the morphological heterogeneity of the labial adhesive apparatus and the substantial division within the molecular phylogeny, we advocate for the elevation of the Labigastromyzon subgenus to the status of a separate genus. Consequently, we have ascertained the validity of the Pseudogastromyzon and Labigastromyzon species, yielding a total of six valid species. To facilitate future research, we present comprehensive descriptions of the redefined species and introduce novel identification keys.
Keywords: Labigastromyzon, mitochondrial genome, phylogeny, Pseudogastromyzon, taxonomy
Jingchen CHEN, Yiyu CHEN, Wenqiao TANG, Haotian LEI, Jinquan YAN and Xiaojing SONG. 2023. Resolving Phylogenetic Relationships and Taxonomic Revision in the Pseudogastromyzon (Cypriniformes, Gastromyzonidae) Genus: Molecular and Morphological Evidence for A New Genus, Labigastromyzon. Integrative Zoology. DOI: 10.1111/1749-4877.12761
Researchgate.net/publication/373874401_phylogenetic_relationships_and_taxonomic_revision_in_Pseudogastromyzon_et_Labigastromyzon
This research elucidates the marked geographical delineation between Pseudogastromyzon and Labigastromyzon genera, with a limited overlapping region. The evolution of labial structures from elementary to intricate morphologies aligns with mitochondrial genome phylogenetics. Notably, the labial adhesive apparatus in Pseudogastromyzon exhibits unimodal and bimodal morphotypes, enhancing the accuracy and efficiency of species identification within this genus.
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in J. Chen, Y. Chen, Tang, Lei, Yan et Song, 2023.
DOI: 10.1111/1749-4877.12761
Researchgate.net/publication/373874401
Abstract
The Pseudogastromyzon genus, consisting of species predominantly distributed throughout southeastern China, has garnered increasing market attention in recent years due to its ornamental appeal. However, the overlapping diagnostic attributes render the commonly accepted criteria for interspecific identification unreliable, leaving the phylogenetic relationships among Pseudogastromyzon species unexplored. In the present study, we undertake molecular phylogenetic and morphological examinations of the Pseudogastromyzon genus. Our phylogenetic analysis of mitochondrial genes distinctly segregated Pseudogastromyzon species into two clades: the Pseudogastromyzon clade and the Labigastromyzon clade. A subsequent morphological assessment revealed that the primary dermal ridge (specifically, the second ridge) within the labial adhesive apparatus serves as an effective and precise interspecific diagnostic characteristic. Moreover, the distributional ranges of Pseudogastromyzon and Labigastromyzon are markedly distinct, exhibiting only a narrow area of overlap. Considering the morphological heterogeneity of the labial adhesive apparatus and the substantial division within the molecular phylogeny, we advocate for the elevation of the Labigastromyzon subgenus to the status of a separate genus. Consequently, we have ascertained the validity of the Pseudogastromyzon and Labigastromyzon species, yielding a total of six valid species. To facilitate future research, we present comprehensive descriptions of the redefined species and introduce novel identification keys.
Keywords: Labigastromyzon, mitochondrial genome, phylogeny, Pseudogastromyzon, taxonomy
Jingchen CHEN, Yiyu CHEN, Wenqiao TANG, Haotian LEI, Jinquan YAN and Xiaojing SONG. 2023. Resolving Phylogenetic Relationships and Taxonomic Revision in the Pseudogastromyzon (Cypriniformes, Gastromyzonidae) Genus: Molecular and Morphological Evidence for A New Genus, Labigastromyzon. Integrative Zoology. DOI: 10.1111/1749-4877.12761
Researchgate.net/publication/373874401_phylogenetic_relationships_and_taxonomic_revision_in_Pseudogastromyzon_et_Labigastromyzon
This research elucidates the marked geographical delineation between Pseudogastromyzon and Labigastromyzon genera, with a limited overlapping region. The evolution of labial structures from elementary to intricate morphologies aligns with mitochondrial genome phylogenetics. Notably, the labial adhesive apparatus in Pseudogastromyzon exhibits unimodal and bimodal morphotypes, enhancing the accuracy and efficiency of species identification within this genus.
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Latest paper on the gymnotiform fauna of the triple border of Brazil, Colombia, and Peru!
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A new species of armored catfish of the genus Scobinancistrus (Loricariidae: Hypostominae) from the Xingu River basin, BrazilAUTHORSHIPSCIMAGO INSTITUTIONS RANKINGSAbstractA new species of Scobinancistrus from the Xingu River, Brazil, is described. It can be distinguished from its congeners by color pattern and a combination of non-exclusive characters: overall body covered by large yellow spaced blotches over a dark background (vs. small round and densely packed spots over light or dark background in S. pariolispos and S. aureatus); lack of orange to yellow/orange distal band on dorsal and caudal fins (vs. presence in S. aureatus), dorsal fin not reaching adipose-fin supporting plate when adpressed (vs. reaching the adipose-fin plate in S. pariolispos and S. aureatus). The new species is only known from a portion of the middle Xingu River, ranging from the Volta Grande do Xingu, an area under a strong anthropic impact due to the construction of the Belo Monte dam, to near the Iriri River confluence with the Xingu River. Aspects concerning the species’ threats and its conservation status are discussed.
Links for full paper https://ni.bio.br/1982-0224-2023-0038/… https://doi.org/10.1590/1982-0224-2023-0038
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Links for full paper https://ni.bio.br/1982-0224-2023-0038/… https://doi.org/10.1590/1982-0224-2023-0038
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Libys callolepis • The First Jurassic Coelacanth from Switzerland
Libys callolepis
Ferrante, Menkveld-Gfeller & Cavin, 2022
DOI: 10.1186/s13358-022-00257-z
Researchgate.net/publication/363791599
twitter.com/Lionel_Cavin
Abstract
Coelacanths form a clade of sarcopterygian fish represented today by a single genus, Latimeria. The fossil record of the group, which dates back to the Early Devonian, is sparse. In Switzerland, only Triassic sites in the east and southeast of the country have yielded fossils of coelacanths. Here, we describe and study the very first coelacanth of the Jurassic period (Toarcian stage) from Switzerland. The unique specimen, represented by a sub-complete individual, possesses morphological characteristics allowing assignment to the genus Libys (e.g., sensory canals opening through a large groove crossed by pillars), a marine coelacanth previously known only in the Late Jurassic of Germany. Morphological characters are different enough from the type species, Libys polypterus, to erect a new species of Libys named Libys callolepis sp. nov. The presence of Libys callolepis sp. nov. in Lower Jurassic beds extends the stratigraphic range of the genus Libys by about 34 million years, but without increasing considerably its geographic distribution. Belonging to the modern family Latimeriidae, the occurrence of Libys callolepis sp. nov. heralds a long period, up to the present day, of coelacanth genera with very long stratigraphic range and reduced morphological disparity, which have earned them the nickname of ‘living fossils’.
Keywords: Sarcopterygii, Actinistia, Libys, New species, Mesozoic, Toarcian, Morphology
Skeleton of Libys callolepis sp. nov. on the part (holotype, NMBE 5034073).
A Photos with osteological details: 1, denticles on the proximal fin rays of the caudal fin. 2, Postparietal shield with the otic sensory canal opening as a deep groove crossed by pillars (white arrowhead). 3, Posterior parietal and the supraorbitals with their pillars (white arrowhead). 4, Consolidated snout with the anterior opening for the rostral organ (white arrowhead). 5, Teeth on the prearticular. B Semi-interpretative line drawing of the specimen
Libys callolepis sp. nov.
Diagnosis: Libys species with the postparietal shield about half the length of the parietonasal shield (the parietonasal is then proportionally shorter than in the type species). The teeth covering the prearticular are very small, and rounded and smooth. Between 41–47 neural arches. Fin rays are slender than in the type species and then not expanded. The scales are strongly ornamented with irregularly sized and elongated round-to-ovoid ridges disposed along a longitudinal axis.
Etymology: From the ancient Greek καλός, kalós, (‘beautiful’, ‘nice’) and λεπίς, lepís, (‘scale’) in reference to the nicely ornamented scales of the species, which differentiates it from the type species.
Holotype and only known specimen: NMBE 5034072 and 5034073, a sub-complete specimen preserved in right lateral view as part and counterpart. Most of the bones, including the scales on the body, are preserved in anatomical position and only the bones of the cheek and the jaw are missing. The specimen is kept in the collections of the Natural History Museum Bern (Canton of Bern, Switzerland).
Horizon and type locality: Toarcian (Lower Jurassic), Creux de l’Ours section, locality of Les Pueys near the Teysachaux summit (Canton of Fribourg, Switzerland).
Skeleton of Libys callolepis sp. nov. on the counterpart (holotype, NMBE 5034072).
A Photos with osteological details: 1, articular head of the scapulocoracoid. 2, Scales on the flank immediately beneath the first anterior dorsal fin. 3, Scales of the lateral line showing the ornamental pattern with the larger central tubercles (white arrowheads point, showed only on one scale). 4, Scales on the ventral flank from the pelvic to the anal fin. 5, Axial mesomere (white arrowhead) surrounded by some fin rays of the anal fin. 6, Axial mesomeres (white arrowhead) partially covered by sediment in the pelvic fin. B Semi-interpretative line drawing of the specimen
Christophe Ferrante, Ursula Menkveld-Gfeller and Lionel Cavin. 2022. The First Jurassic Coelacanth from Switzerland. Swiss Journal of Palaeontology. 141: 15. DOI: 10.1186/s13358-022-00257-z
Researchgate.net/publication/363791599_The_first_Jurassic_coelacanth_from_Switzerland
twitter.com/Lionel_Cavin/status/1575729513513684993
==========================
Libys callolepis
Ferrante, Menkveld-Gfeller & Cavin, 2022
DOI: 10.1186/s13358-022-00257-z
Researchgate.net/publication/363791599
twitter.com/Lionel_Cavin
Abstract
Coelacanths form a clade of sarcopterygian fish represented today by a single genus, Latimeria. The fossil record of the group, which dates back to the Early Devonian, is sparse. In Switzerland, only Triassic sites in the east and southeast of the country have yielded fossils of coelacanths. Here, we describe and study the very first coelacanth of the Jurassic period (Toarcian stage) from Switzerland. The unique specimen, represented by a sub-complete individual, possesses morphological characteristics allowing assignment to the genus Libys (e.g., sensory canals opening through a large groove crossed by pillars), a marine coelacanth previously known only in the Late Jurassic of Germany. Morphological characters are different enough from the type species, Libys polypterus, to erect a new species of Libys named Libys callolepis sp. nov. The presence of Libys callolepis sp. nov. in Lower Jurassic beds extends the stratigraphic range of the genus Libys by about 34 million years, but without increasing considerably its geographic distribution. Belonging to the modern family Latimeriidae, the occurrence of Libys callolepis sp. nov. heralds a long period, up to the present day, of coelacanth genera with very long stratigraphic range and reduced morphological disparity, which have earned them the nickname of ‘living fossils’.
Keywords: Sarcopterygii, Actinistia, Libys, New species, Mesozoic, Toarcian, Morphology
Skeleton of Libys callolepis sp. nov. on the part (holotype, NMBE 5034073).
A Photos with osteological details: 1, denticles on the proximal fin rays of the caudal fin. 2, Postparietal shield with the otic sensory canal opening as a deep groove crossed by pillars (white arrowhead). 3, Posterior parietal and the supraorbitals with their pillars (white arrowhead). 4, Consolidated snout with the anterior opening for the rostral organ (white arrowhead). 5, Teeth on the prearticular. B Semi-interpretative line drawing of the specimen
Libys callolepis sp. nov.
Diagnosis: Libys species with the postparietal shield about half the length of the parietonasal shield (the parietonasal is then proportionally shorter than in the type species). The teeth covering the prearticular are very small, and rounded and smooth. Between 41–47 neural arches. Fin rays are slender than in the type species and then not expanded. The scales are strongly ornamented with irregularly sized and elongated round-to-ovoid ridges disposed along a longitudinal axis.
Etymology: From the ancient Greek καλός, kalós, (‘beautiful’, ‘nice’) and λεπίς, lepís, (‘scale’) in reference to the nicely ornamented scales of the species, which differentiates it from the type species.
Holotype and only known specimen: NMBE 5034072 and 5034073, a sub-complete specimen preserved in right lateral view as part and counterpart. Most of the bones, including the scales on the body, are preserved in anatomical position and only the bones of the cheek and the jaw are missing. The specimen is kept in the collections of the Natural History Museum Bern (Canton of Bern, Switzerland).
Horizon and type locality: Toarcian (Lower Jurassic), Creux de l’Ours section, locality of Les Pueys near the Teysachaux summit (Canton of Fribourg, Switzerland).
Skeleton of Libys callolepis sp. nov. on the counterpart (holotype, NMBE 5034072).
A Photos with osteological details: 1, articular head of the scapulocoracoid. 2, Scales on the flank immediately beneath the first anterior dorsal fin. 3, Scales of the lateral line showing the ornamental pattern with the larger central tubercles (white arrowheads point, showed only on one scale). 4, Scales on the ventral flank from the pelvic to the anal fin. 5, Axial mesomere (white arrowhead) surrounded by some fin rays of the anal fin. 6, Axial mesomeres (white arrowhead) partially covered by sediment in the pelvic fin. B Semi-interpretative line drawing of the specimen
Christophe Ferrante, Ursula Menkveld-Gfeller and Lionel Cavin. 2022. The First Jurassic Coelacanth from Switzerland. Swiss Journal of Palaeontology. 141: 15. DOI: 10.1186/s13358-022-00257-z
Researchgate.net/publication/363791599_The_first_Jurassic_coelacanth_from_Switzerland
twitter.com/Lionel_Cavin/status/1575729513513684993
==========================
Labeo mbimbii & L. manasseeae • Two New Labeo (Cypriniformes: Cyprinidae: Labeoninae) Endemic to the Lulua River in the Democratic Republic of Congo (Kasai Ecoregion); a Hotspot of Fish Diversity in the Congo Basin
Labeo mbimbii & L. manasseeae
Liyandja & Stiassny, 2023
DOI: 10.1206/3999.1
URI: hdl.handle.net/2246/7321
Researchgate.net/publication/370855834
Abstract
Labeo mbimbii, n. sp., and Labeo manasseeae, n. sp., two small-bodied Labeo species, are described from the lower and middle reaches of the Lulua River (Kasai ecoregion, Congo basin) in the Democratic Republic of Congo. The two new species are members of the L. forskalii species group and are genetically distinct from all other species of that clade. Morphologically they can be distinguished from central African L. forskalii group congeners except L. dhonti, L. lukulae, L. luluae, L. parvus, L. quadribarbis, and L. simpsoni in the possession of 29 or fewer (vs. 30 or more) vertebrae and from those congeners by a wider interpectoral, among other features.
The two new species are endemic to the Lulua River and, although overlapping in geographical range and most meristic and morphometric measures, are readily differentiated by differing numbers of fully developed supraneural bones, predorsal vertebrae, snout morphology, and additional osteological features. The description of these two species brings the total of Labeo species endemic to the Lulua basin to three. The third endemic species, L. luluae, was previously known only from the juvenile holotype, but numerous additional specimens have now been identified. The cooccurrence of 14 Labeo species in the Lulua River, three of which are endemic, highlights this system as a hotspot of Labeo diversity in the Congo basin and across the continent.
Keywords: Labeo mbimbii, Labeo manasseeae, Labeo, Classification, Cyprinida, Congo (Democratic Republic), Congo, Classification, Fishes
Labeo mbimbii, n. sp. Holotype (AMNH 277862, AMCC 249232):
A. lateral view, immediately postmortem; B. in preservation, lateral view; C. ventral view; and D. dorsal view. Scale bar = 1 cm.
Labeo manasseeae, n. sp. Holotype (AMNH 269110, AMCC 249240):
A. immediately postmortem; B. in preservation, lateral view; C. ventral view; and D. dorsal view. Scale bar = 1 cm
Labeo mbimbii, n. sp.
Labeo manasseeae, n. sp.
Tobit L.D. Liyandja and Melanie L.J. Stiassny. 2023. Description of Two New Labeo (Labeoninae; Cyprinidae) Endemic to the Lulua River in the Democratic Republic of Congo (Kasai Ecoregion); a Hotspot of Fish Diversity in the Congo Basin. American Museum Novitates. (3999); 1-22. DOI: 10.1206/3999.1 URI: hdl.handle.net/2246/7321
Researchgate.net/publication/370855834_Description_of_two_new_Labeo_endemic_to_the_Lulua_River_in_DR_Congo
==========================
Labeo mbimbii & L. manasseeae
Liyandja & Stiassny, 2023
DOI: 10.1206/3999.1
URI: hdl.handle.net/2246/7321
Researchgate.net/publication/370855834
Abstract
Labeo mbimbii, n. sp., and Labeo manasseeae, n. sp., two small-bodied Labeo species, are described from the lower and middle reaches of the Lulua River (Kasai ecoregion, Congo basin) in the Democratic Republic of Congo. The two new species are members of the L. forskalii species group and are genetically distinct from all other species of that clade. Morphologically they can be distinguished from central African L. forskalii group congeners except L. dhonti, L. lukulae, L. luluae, L. parvus, L. quadribarbis, and L. simpsoni in the possession of 29 or fewer (vs. 30 or more) vertebrae and from those congeners by a wider interpectoral, among other features.
The two new species are endemic to the Lulua River and, although overlapping in geographical range and most meristic and morphometric measures, are readily differentiated by differing numbers of fully developed supraneural bones, predorsal vertebrae, snout morphology, and additional osteological features. The description of these two species brings the total of Labeo species endemic to the Lulua basin to three. The third endemic species, L. luluae, was previously known only from the juvenile holotype, but numerous additional specimens have now been identified. The cooccurrence of 14 Labeo species in the Lulua River, three of which are endemic, highlights this system as a hotspot of Labeo diversity in the Congo basin and across the continent.
Keywords: Labeo mbimbii, Labeo manasseeae, Labeo, Classification, Cyprinida, Congo (Democratic Republic), Congo, Classification, Fishes
Labeo mbimbii, n. sp. Holotype (AMNH 277862, AMCC 249232):
A. lateral view, immediately postmortem; B. in preservation, lateral view; C. ventral view; and D. dorsal view. Scale bar = 1 cm.
Labeo manasseeae, n. sp. Holotype (AMNH 269110, AMCC 249240):
A. immediately postmortem; B. in preservation, lateral view; C. ventral view; and D. dorsal view. Scale bar = 1 cm
Labeo mbimbii, n. sp.
Labeo manasseeae, n. sp.
Tobit L.D. Liyandja and Melanie L.J. Stiassny. 2023. Description of Two New Labeo (Labeoninae; Cyprinidae) Endemic to the Lulua River in the Democratic Republic of Congo (Kasai Ecoregion); a Hotspot of Fish Diversity in the Congo Basin. American Museum Novitates. (3999); 1-22. DOI: 10.1206/3999.1 URI: hdl.handle.net/2246/7321
Researchgate.net/publication/370855834_Description_of_two_new_Labeo_endemic_to_the_Lulua_River_in_DR_Congo
==========================
A new species of Trimma of the T. taylori species group (Teleostei: Gobiidae) from the Red Sea, Indian Ocean PISCESTAXONOMYPYGMYGOBYCORAL REEF GOBIESSAUDI ARABIACORAL ECOSYSTEMS AbstractA new species of Trimma is described from the Red Sea along the Saudi Arabian coast. Specimens and/or photographs of this species are available from the Egyptian Red Sea to Eritrea. These specimens, formerly identified as T. taylori, differ from all other samples from the Indo-Pacific currently identified as T. taylori in having 9 and 8–9 dorsal- and anal-fin rays respectively (vs. usually 10 and 10 rays), 13 pectoral-fin rays (vs. usually 14 rays), and cycloid scales covering the entire predorsal region from the upper base of the pectoral fin anterior to a convex line posterodorsally to just lateral to the base of the sixth first dorsal-fin spine (vs. predorsal region mostly or entirely covered with ctenoid scales). In addition, specimens from the Red Sea form a monophyletic lineage in a Maximum Likelihood analysis of the COI gene. In this tree, the new species is the sister group to a clade composed of three lineages. One is composed of specimens from the Maldives, which is the sister group of a single available specimen from the Seychelles. These two together are the sister group of specimens of a widespread western Pacific clade.
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Aquatic Conservation: Marine and Freshwater Ecosystems
RESEARCH ARTICLE
Open Access
Alternative conservation outcomes from aquatic fauna translocations: Losing and saving the Running River rainbowfish
Karl Moy, Jason Schaffer, Michael P. Hammer, Catherine R. M. Attard, Luciano B. Beheregaray, Richard Duncan, Mark Lintermans, Culum Brown, Peter J. Unmack
First published: 16 October 2023
https://doi.org/10.1002/aqc.4023
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1 INTRODUCTIONThe translocation of alien species is a major threat to many ecosystems worldwide (Vitousek et al., 1997; Clavero & García-Berthou, 2005; Gallardo et al., 2016). Globally, the rate of translocations has been increasing (Seebens et al., 2017), with alien species currently present on every continent (Prins & Gordon, 2014). Although there has been considerable research examining the adverse effects of alien species (McNeely, 2001; Prins & Gordon, 2014), translocations can also be an effective tool for conservation and management (Minckley, 1995; Tuberville et al., 2005; IUCN/SSC, 2013). Translocation has become a key tool for conserving freshwater fishes, using both wild and captive-bred fishes (Minckley, 1995; Lintermans, 2013a; Lintermans et al., 2015). When referring to different types of conservation translocations, this article follows the definitions provided by the International Union for Conservation of Nature Species Survival Commission (IUCN/SSC, 2013).
Most early conservation translocations of fish have involved large-bodied threatened species that were often potential angling targets (Minckley & Deacon, 1991; Lintermans et al., 2015). However, the practice has also been applied to smaller threatened fishes (Minckley & Deacon, 1991; Hammer et al., 2013; Lintermans et al., 2015; Tatár et al., 2016). The continued existence of certain species, such as the Pedder galaxias (Galaxias pedderensis) is solely the result of conservation translocations (Chilcott et al., 2013), whereas the conservation status of several Critically Endangered species, such as the red-finned blue-eye (Scaturiginichthys vermeilipinnis; Kerezsy & Fensham, 2013) and several other galaxiid species (Koster, 2003; Hardie, Barmuta & White, 2006; Ayres, Nicol & Raadik, 2012) have benefited substantially from translocations.
A review of factors influencing the success of freshwater fish reintroductions reported that second to addressing the cause of initial decline, habitat-related factors were the greatest predictors of reintroduction success (Cochran-Biederman et al., 2015). The importance of suitable habitat in determining the success or failure of conservation introductions is echoed by studies of invasive fish species, which have found that if the habitat characteristics of the receiving environment are suitable then an invasion is likely to succeed, regardless of other factors (Moyle & Light, 1996a; Moyle & Light, 1996b; Harris, 2013). That an introduction is likely to fail in the absence of suitable habitat seems straightforward; however, some reintroductions may fail even in the presence of adequate habitat (Barlow, Hogan & Rodger, 1987; Leggett & Merrick, 1997).
Out of all failed conservation translocations of fish, 71% used captive-reared fish (Cochran-Biederman et al., 2015). Captive-reared fish are often raised under conditions that are vastly different from the environment into which they are released (Brown, Davidson & Laland, 2003). Consequently, captive-reared fish often exhibit behaviours that are detrimental to their survival in the wild, and as a result often suffer from high mortality rates once released (Brown & Day, 2002; Ebner, Thiem & Lintermans, 2007; Sparrevohn & Støttrup, 2007), which is a prevalent problem across fauna groups (Berger-Tal, Blumstein & Swaisgood, 2020). The behavioural impacts of captive rearing have been known for some time (Brown & Day, 2002), with captive-reared fish showing deficiencies in key behaviours such as predator recognition and avoidance (Alvarez & Nicieza, 2003; Ebner, Thiem & Lintermans, 2007) and foraging skills (Brown & Laland, 2002; Brown, Davidson & Laland, 2003). Studies on the success of conservation introductions of freshwater fishes within Australia (Ebner, Thiem & Lintermans, 2007; Ebner, Johnston & Lintermans, 2009; Brown et al., 2012) and abroad (Alvarez & Nicieza, 2003) suggest that predation and competition are likely to play a major role in translocation success. Brown, Davidson & Laland (2003) showed that environmental enrichment and exposure to live foods resulted in fish being better able to handle novel prey items. Meanwhile, several studies have shown that repeated exposure to predators, or their stimulus (e.g. scent or pictures), will improve the predator avoidance behaviours of captive-bred fish (Brown, 2003a; Vilhunen, 2006; Hutchison et al., 2012; Abudayah & Mathis, 2016). As a result, research and implementation of environmental enrichment and predator training of captive-reared fish is becoming more commonplace (Vilhunen, 2006; Hammer et al., 2012; Roberts et al., 2014; Lintermans et al., 2015).
Most research investigating methods to improve the survival of captive-reared fishes has taken place overseas, although some recent research has been conducted in Australia (Hutchison et al., 2012). In both cases, the research investigating introduction success has focused almost entirely on large-bodied, predatory, recreationally important species, such as brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) (Brown & Smith, 1998; Alvarez & Nicieza, 2003; Brockmark, Adriaenssens & Johnsson, 2010), or percichthyids (Ebner, Thiem & Lintermans, 2007; Ebner & Thiem, 2009; Hutchison et al., 2012). However, of the 17 Australian species used in conservation introductions documented by Lintermans et al. (2015), 10 were small-bodied species. Small-bodied species usually have vastly different requirements compared with large-bodied species, and a conservation measure that works well for large species may not be as effective for smaller species (e.g. growing them to a large size to prevent predation).
1.1 Study organism backgroundThe extinctions and declines of native fishes resulting from hybridization with alien species have been well documented throughout Europe and North America (Hitt et al., 2003; Rosenfield & Kodric-Brown, 2003; Meldgaard et al., 2007; Ludwig et al., 2009). Compared with other countries, introgressive hybridization with alien species has not typically been considered a threat to Australia’s native biodiversity (Hitt et al., 2003; Meldgaard et al., 2007; Ludwig et al., 2009) because most alien species have originated from other continents with biota that are taxonomically distant (Lintermans, 2013a). However, high levels of genetic structuring between populations as well as many new cryptic species were identified by recent broadscale genetic studies of Australian freshwater fishes (Hammer et al., 2007; Raadik, 2014; Shelley et al., 2018). Accordingly, introgressive hybridization caused by translocations of ‘native’ species outside their natural range, or from one part of a species range to another, has more recently been recognized as a threat to conservation for Australian freshwater fishes (Lintermans et al., 2005; Harris, 2013; Couch et al., 2016).
Endemic to Australia and New Guinea, the family Melanotaeniidae, or rainbowfishes, contains more than 110 species with multiple undescribed taxa (Unmack, Allen & Johnson, 2013). The genus Melanotaenia is by far the most numerous and widespread in Australia, occurring throughout the northern half of the continent and into south-eastern regions (Unmack, Allen & Johnson, 2013). There are several ‘lineages’ within the genus, and species within the same lineage rarely co-occur (Unmack, Allen & Johnson, 2013). In 2016, the Australian Society for Fish Biology (ASFB) listed four Melanotaenia species as Vulnerable, Endangered, or Critically Endangered, owing to introgressive hybridization with a widespread member of the genus (Lintermans, 2016), with a subsequent International Union for Conservation of Nature (IUCN) assessment confirming their threatened status (Hammer, Unmack & Brown, 2019b).
One of the species listed by the ASFB and the IUCN was the Running River rainbowfish (RRR Melanotaenia sp.). This species was first recorded in 1981 as a phenotypically unique population of rainbowfish from the usual native eastern rainbowfish (Melanotaenia splendida splendida) found in most rivers in the region (Martin & Barclay, 2016). Further collections across the region suggested that there was a complex of different rainbowfish populations, the taxonomy of which was unclear (Martin & Barclay, 2016). As part of a broader rainbowfish research project, fieldwork was conducted across the Burdekin River basin in August 2015 to try to resolve the taxonomic status of the various rainbowfish populations native to the region. During this fieldwork it was discovered that eastern rainbowfish had colonized the reach of Running River containing RRR, as well as being established in large numbers further upstream at Hidden Valley (Unmack & Hammer, 2015), an area previously lacking any rainbowfish (Martin & Barclay, 2016). It is unclear whether this represents a new translocation, or whether it represents downstream dispersal from earlier recorded translocated populations above Paluma Dam (although recent searches above Paluma Dam have failed to find any rainbowfish) (Martin & Barclay, 2016). Subsequent genetic and morphological examination supports the recognition of RRR as a separate species (P. Unmack, M. Hammer, G. Allen, unpublished data). As currently recognized, RRR is restricted to 13 km of Running River between two gorges (Figure 1). Running River is a major tributary to the Burdekin River, one of Australia’s larger river basins, situated on the north-eastern coast of Queensland (Pusey, Arthington & Read, 1998). The lower gorge prevents the upstream movement of eastern rainbowfish, whereas the upper gorge prevents the movement of RRR further upstream.
FIGURE 1
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Map of the study area showing the location of Puzzle and Deception creeks and their positions relative to Running River and its gorges. Purple arrows indicate the range of Running River rainbowfish, whereas orange arrows indicate the range of the eastern rainbowfish (Melanotaenia splendida). Created by AWC Spatial Officer Tani Cooper, and used with permission from the Australian Wildlife Conservancy.Once eastern rainbowfish had been detected in Running River above the upper gorge in 2015 it was realized that RRR was at risk of extinction via hybridization, as no members of the Australis lineage (Unmack, Allen & Johnson, 2013) of rainbowfishes are ever found in sympatry. At this point it was apparent that this population was distinct and worth conserving, but its taxonomic status would not be clear until genetic work had been conducted. Initially, 52 live wild fish were collected and then brought back to the University of Canberra as an insurance population. As this research lacked any formal funding, crowdfunding was initiated via the University of Canberra Foundation to cover the costs of genotyping potential broodstock, and keeping, breeding, and shipping the fish, and used internal University of Canberra funding to fund a postgraduate research project. Funds were sought by directly contacting various aquarium societies, primarily from North America, Australia, and Europe, as well as being solicited from members of the Australia New Guinea Fishes Association during presentations and in their journal Fishes of Sahul. In addition, we put out calls for donations via social media in various Australian native fish-related Facebook groups and in the aquarium magazine Amazonas. There is tremendous worldwide interest in rainbowfishes from aquarium hobbyists, as they are brightly coloured and easy to keep and breed. Many aquarium hobbyists, clubs, and businesses have a strong conservation ethos and are enthusiastic about supporting projects like ours by donating money. Once preliminary data on the taxonomy of rainbowfishes in the Burdekin River basin had been collected it became clear that RRR was a unique taxon from the Australis lineage and action was needed to save it.
The only conservation options available for RRR were either to hold the fish in captivity for the long term or to find locations where they could be translocated to, as it would take a massive effort to remove the eastern rainbowfish from upper Running River and then restore RRR in their native range. Maintaining the species in wild habitats was the most feasible option, thus the next challenge was to determine whether any suitable sites for translocation might exist.
The eastern rainbowfish is a capable disperser, occupying most habitats throughout its range, unless there are significant barriers to prevent movement, and thus finding habitats where it is absent is unusual. The region around Running River is seasonally arid and most small creeks in the region do not hold water permanently. The middle to lower section of Running River has two larger tributaries, Deception Creek and Puzzle Creek, which are located on Mount Zero–Taravale (Figure 1), covered by two pastoral leases owned and managed by the Australian Wildlife Conservancy (AWC, a not-for-profit conservation organization). Both creeks have sections that flow through gorges or rocky reaches that hold permanent water, and both were reported to have fishes of unknown species present (T. White, manager of the AWC Mount Zero–Taravale Sanctuary). Both creeks were sampled in February 2016, with Deception Creek having a large population of spangled perch (Leipotherapon unicolor), as well as a few purple spotted gudgeon (Mogurnda sp.), whereas Puzzle Creek had the same species, but the uppermost section above a waterfall only contained an abundant population of purple spotted gudgeon. Deception Creek flows into Running River below the lower gorge, with eastern rainbowfish native to its lower reaches. One medium-sized waterfall was located on Deception Creek approximately 12 km upstream from the confluence with Running River. Puzzle Creek flows into Running River in the middle of the upper gorge, which historically probably lacked rainbowfish; in addition, it has several major waterfalls of 10–20 m in height present along its course. As both creeks lacked rainbowfish they were considered suitable long-term translocation sites. This was an extraordinarily fortuitous situation given the lack of permanent streams in the area and the lack of eastern rainbowfish in both these streams. Any translocations into other rivers would have had impacts on native rainbowfish populations located in downstream reaches, whereas the eastern rainbowfish in lower Running River already had a potential influx of RRR from upstream.
As small-bodied freshwater fishes commonly have a high risk of extinction (Reynolds, Webb & Hawkins, 2005; Olden, Hogan & Zanden, 2007; Kopf, Shaw & Humphries, 2017; Lintermans et al., 2020), there is a need for a better understanding of the factors influencing, and methods for improving, the survival of captive-bred small-bodied freshwater fishes once released, to reduce the chance of failure. One example of this type of failure is the previous attempts to return Melanotaenia eachamensis (Lake Eacham rainbowfish) to Lake Eacham after they were extirpated owing to the introduction of other fishes (Barlow, Hogan & Rodger, 1987). A captive breeding programme was established (Barlow, Hogan & Rodger, 1987) that produced 3,000 fish, which were then released into the lake; however, subsequent surveys failed to detect any survivors (Brown et al., 2012). Subsequent research showed that captive rainbowfish can behave very differently from wild fish (Brown & Warburton, 1997; Brown & Warburton, 1999a; Kydd & Brown, 2009). This highlights the complexity that can be involved in obtaining successful reintroduction outcomes.
The main goals of the present study were to initiate a conservation programme for a recently recognized, undescribed, small-bodied rainbowfish, the Running River rainbowfish (RRR, Melanotaenia sp.). This was achieved through the design and implementation of a conservation strategy that used captive breeding and translocations to conserve the species and to evaluate the success of the strategy to inform future efforts. The study also documented the history of the species, the discovery of the translocation of eastern rainbowfish, and how crowdfunding was used to support the project. This article reports on the results of experiments conducted to examine the role of predator training on translocation success. However, these can be difficult to assess because of the limited replication, small sample sizes, and perturbations caused by weather events.
2 METHODS2.1 Captive breedingIn 2015, 52 RRR were collected from Running River and transported to the University of Canberra. Broodstock were genotyped using single nucleotide polymorphisms (SNPs) based on DNA from fin clips and compared with wild fish that had been collected and preserved in liquid nitrogen in 1997 (18 years earlier), to ensure genetic purity. These fish were set up as 26 breeding pairs and used as broodstock for Deception Creek releases. In February 2016 additional wild fish were collected, with 32 fish genotyped and added as broodstock for Puzzle Creek releases. Fish were spawned in 17 groups of two males and two females. Some breeding groups had extra individuals added such that half the breeding groups consisted of five, six, or seven individuals. From these 26 pairs the target was to produce 110 offspring from each breeding group to ensure that each group made an equal contribution to the next generation. A target of 260 offspring was set for the 17 breeding groups. Approximately 6,900 fish were produced at the University of Canberra, 2,700 in the first round of breeding for Deception Creek and 4,200 in the second round of breeding for Puzzle Creek. Eggs were collected on synthetic wool mops placed into breeding tanks. After 2 days of spawning, the mops were transferred to small fish tanks (40 × 20 × 20 cm) and the juvenile fish were raised for approximately 2 months before being transferred to larger tanks (91 × 35 × 45 cm). Breeding and rearing tanks had painted sides and bottom and a sponge filter. Larvae were started on a diet of live vinegar eels (Turbatrix aceti), and as they grew larger moved onto a diet of juvenile brine shrimp (Artemia sp.) over the course of about a week, together with commercial flake food.
Once large enough for transport, the fish were air-freighted to James Cook University (JCU) Townsville and distributed evenly into 10 outdoor rearing ponds (108 cm in diameter and 36 cm deep, 330 L) to grow out. At JCU, the fish were fed with commercially available flake food three times a day and a mixture of frozen brine shrimp and blood worms (Chironomidae) once a day. All rearing ponds contained several large river stones and plastic mesh 50 × 100 cm with holes of 2.5 cm in diameter, which was contorted into different shapes and added to provide cover. This was to encourage natural behaviours such as using cover to escape threats, establishing and holding territories, and foraging, which have previously been found to result in improved survival rates (Brown, Davidson & Laland, 2003; Roberts et al., 2014). Although there were differences in the shape and size of the rocks, all the ponds were arranged in a similar pattern.
2.2 Predator trainingRelease sites in Deception Creek were known to contain a potential predator, the spangled perch. To test the impact of predator training, half of the rearing ponds were exposed to an adult spangled perch of approximately 15 cm in length placed in a 25 × 25 cm ‘mesh box’ made from plastic 2.5-cm mesh within the outdoor pond. RRR were able to swim freely in and out of the mesh box. In addition to providing the predator, a cutaneous alarm cue was also provided, which is often released when the skin of a fish is damaged and can be used in associative learning (Brown, 2003b; Brown & Chivers, 2007; Abudayah & Mathis, 2016). To obtain this alarm cue one RRR was euthanized (with an overdose of clove oil) per week of training, crushed up, mixed with water, and sieved to remove larger fragments. This solution was then frozen in an ice-cube tray and one cube was added at the same time as the spangled perch in the hope that juvenile RRR would associate the olfactory cue of dead or injured conspecifics with the stimulus of a spangled perch. The spangled perch was left in the rearing pond for 15 min per day for 7 days immediately before the fish were released into the wild.
2.3 Release sitesDeception Creek, which flows into Running River just below the lowermost gorge, and Puzzle Creek, which flows into Running River just above the uppermost gorge, were identified as the best potential translocation sites (Figure 1). Both creeks contained barriers to the upstream dispersal of rainbowfish (Figure 1) and already had resident fish fauna, meaning that the potential impacts on invertebrates and frogs of introducing a new fish species was minimal. Throughout most of the year Deception Creek consists of disconnected pools without flow, whereas Puzzle Creek flows for most of the year but with reduced/disconnected pools during periods of low rainfall. Purple spotted gudgeon was found in both creeks, whereas spangled perch was found throughout Deception Creek and in reaches below the release sites in Puzzle Creek. Although both species have the potential to prey upon small fishes, spangled perch grows to a much larger size than purple spotted gudgeon and are more active hunters (Pusey, Kennard & Arthington, 2004). Therefore, as the predation pressure on small fishes in Deception Creek was likely to be higher than that in Puzzle Creek, releases into Deception Creek were used to assess the effect of predator training on translocation success.
In an attempt to isolate the effects of predator training, the release sites within Deception Creek were paired based on similarities between habitat variables, with one site randomly selected to receive trained fish and with the other site receiving untrained fish. Puzzle Creek release sites were also assessed, but owing to the lower number of accessible pools, habitat assessments were only used to identify suitable release sites. The habitat variables examined were pool length, average pool width, substrate composition, average depth, deepest point, and riparian cover. Pool length was measured from the uppermost water edge to the farthest downstream water edge. Average pool width was calculated by taking three measurements at 25%, 50%, and 75% of the total length of the pool using a tape measure. A transect comprising five sample points was taken along each width measurement at 0% (+25 cm), 25%, 50%, 75%, and 100% (−25 cm) of the channel width. At each sample point, depth, substrate composition, macrophyte cover, and leaf litter were measured. Macrophyte cover, substrate, and leaf litter were all considered independent of one another. Macrophyte cover was defined as all emergent and submerged vegetation within the quadrat. Riparian cover was defined as the percentage of the bank covered by vegetation. Riparian cover was estimated by eye to the nearest 5%, whereas depth was measured using a metal ruler. All other variables were measured using a 50 × 50 cm quadrat.
Release pools were paired based on similar size, riparian cover, and substrate, in that order, with one pool randomly assigned to trained or untrained fish. As there were limits to the number of fish that could be produced, the 2,500 that were bred were divided into groups of 250 for release. This number was chosen to balance the number of release sites against the number of fish in each release.
2.4 Release and monitoringTen releases of 250 fish were performed across 10 release sites in Deception Creek between 2 November 2016 and 13 January 2017. Releases were made in groups of 250 to provide five replicates of each treatment (trained and untrained), as grow-out facilities consisted of 10 ponds. At release, the fish were approximately 3 cm in total length, on average, but varied from approximately 2 to 5 cm. Deception Creek releases occurred once every week or so; however, there was no assigned order for which releases happened when, owing to logistical constraints regarding predator avoidance training. Fish were transported from rearing ponds at JCU to their release sites in 20-L plastic buckets. Buckets were filled to one-third full and water was dosed with sea salt at 2.6 g L−1 and API Stress Coat® (Mars Fishcare, Inc., Chalfont, PA, USA), dosed at 0.8 ml L−1. Fish were delivered to their release site on the same day as collection from the rearing ponds in all but one case, which was hampered by heavy rainfall. In this instance, fish were held in buckets for 2 days with a daily water change, before delivery to their release site. Fish were held instream at the release site overnight in a holding net with dimensions of 1 × 1 × 1 m made from shade cloth and polyvinyl chloride (PVC) pipe. This allowed the fish to acclimatize to water conditions without any predation pressure. The following day the fish were released into the pool by gently up-ending the holding net.
After release, snorkel surveys were used to estimate the abundance of spangled perch and RRR in each pool. Snorkel surveys were chosen as the survey method needed to be non-destructive and non-intrusive. A small pilot study was conducted early on, comparing the detection rates among snorkel surveys, bait traps, and baited remote underwater video; however, the latter two methods did not detect a single RRR (K. Moy, unpublished data). Owing to logistical constraints, surveys occurred somewhat opportunistically. However, at least one survey was undertaken in the first week following release and this was often followed by other surveys up to 56 days after release. Forty-one surveys across five untrained and two trained release sites were made between 2 November 2016 and 5 January 2017. A large rainfall event (over 200 ml across 4 days at the nearest rainfall gauge) occurred in early January 2017, which caused flooding and restored flow to the channel, reconnecting the release pools before the predator training experiment in Deception Creek could be completed. This prevented any survey data being collected for the final three releases, which were all of trained fish. Snorkel surveys consisted of three passes: along the left bank, then the right bank, and with a final pass down the centre of the pool. The researcher kept a steady pace to prevent any double counting of fish, and on a waterproof notepad recorded a tally of the total number seen as well as the maximum seen at any one time, with a separate count for larvae. Spangled perch were also recorded in this way to estimate predator density. Follow-up surveys were undertaken for all sites in Deception Creek in May and October 2017.
After the first field season, the extent of fish occurrence throughout each drainage was mapped by walking along the creek, upstream and downstream from the uppermost and lowermost pools, respectively, and stopping at each pool encountered for 5 min to observe the presence or absence of rainbowfish. If no rainbowfish were observed within 5 min, the researcher moved to a different region of the pool and continued to observe for a further 5 min. If no rainbowfish were observed, the next pool downstream or upstream was also checked. This was repeated until three pools in a row were found without rainbowfish. This was carried out for Deception Creek in May and October 2017 and in April 2018. An attempt was made to map the extent of RRR in Deception Creek after the large rainfall event in early January 2017, following the same protocol above, but was hampered by low visibility owing to the increased turbidity.
Four releases, each consisting of 375 untrained fish, were made into four sites across Puzzle Creek in May 2017 in the same manner as those made into Deception Creek. Although the fish released into Puzzle Creek were the same size as those released into Deception Creek, only 1,500 of the originally intended 4,000 fish were released because of attrition in the rearing ponds. Owing to funding and weather constraints on fieldwork, no monitoring was undertaken in the weeks immediately after release for the Puzzle Creek releases. The planned monitoring of Puzzle Creek in October 2017 was prevented by a large rainfall event, but a survey of all release sites following the same protocol described above took place in May 2018. Distribution mapping for Puzzle Creek took place in May 2018 following the same protocol used for Deception Creek. Research was conducted under the University of Canberra Animal Ethics Committee approval CEAE 16-03.
2.5 AnalysisTwo-sample Student’s t-tests were used to test for differences in abundance in Deception Creek following release for trained versus untrained fish sites, paired by habitat variables, whereas an independent-samples Student’s t-test was used to look for differences in density between releases made before and after flooding. For observations not made in the month immediately after release, measures of abundance from the surveys were converted into measures of density by dividing the abundance by the length of the pool. Two-sample Student’s t-tests were used to determine differences in density between trained and untrained release sites within Deception Creek from data collected during May and October (approximately 6 and 8 months from release).
3 RESULTS3.1 CrowdfundingA total of AU$26,465 was raised from donations made by individuals (AU$4,435), companies (AU$1,150), and aquarium clubs (AU$20,880), with donations received from Australia, USA, Canada, Switzerland, and Germany. The largest donation was AU$10,000 from the Aquarium Society of Victoria. Most donations from aquarium clubs were solicited through personal contacts. Without these funds the project would have been impossible and RRR would be close to extinction. Crowdfunding covered all of the DNA sequencing costs, fish food, and live fish shipping, which cost approximately AU$12,000 in total. The bulk of the remaining funds were used over subsequent years to continue monitoring the wild and translocated populations, including further genetic monitoring.
3.2 HabitatIn October 2016, release sites in Deception Creek varied between 100 and 280 m in length and between 8 and 14 m in width. The average depth varied between 42 and 113 cm, whereas the deepest points ranged from 1.65 to 3.00 m. Riparian cover ranged from 60% to 99%. Substrate was dominated by sand (45%–95%), followed by boulder (0%–26%), bedrock (0%–24%), and cobble (0%–17%). On average, aquatic plants (macrophytes and charophytes) covered approximately 40% of the substrate, whereas leaf litter covered approximately 25% of the substrate. Release sites within Puzzle Creek were between 150 and 265 m in length and between 9.9 and 22.4 m in width, with the average depth ranging between 84 and 125 cm, and with the deepest points ranging from 1.70 to 2.75 m. Riparian cover varied between 95% and 80%, whereas the average substrate was dominated by sand (40%–60%), followed by bedrock (3%–43%), cobble (7%–32%), and boulder (2%–7%). On average, aquatic macrophytes and charophytes covered 20% of the substrate, whereas leaf litter covered 20% of the substrate.
3.3 Predator effectsThere was no significant difference in abundance or density of adult fish between trained and untrained release sites at any point after release (Table 1). Of the seven releases in Deception Creek before flooding, fish failed to become established at only one site following the release of untrained fish. This site was surveyed five times from 2–31 days after release without a single RRR observed, and was similar to other sites in every way. At the remaining sites the abundance of released fish appeared to decline continuously over the 56-day monitoring period for both treatments at sites where samples were collected for more than 2 weeks following release (Figure 2). However, linear regression analysis did not provide statistical support for this decline (t = 0.27, P = 0.788), although this could have been the result of the low detection power caused by small sample sizes and variation in detectability. Increasing numbers of detected fish at some sites over the first few days after release (Figure 2) were probably the result of fish becoming more familiar with their new environment.
TABLE 1. Statistical output comparing trained and untrained releases of fish. A Welch’s t-test (W) compared the total observed abundance at 2–3 weeks from release, whereas a paired Student’s t-test (P) compared the density of adults at 6 and 11 months from release. The standard error (SE) was calculated from 11 abundance observations between two sites that all fell within 4 days of one another, converted to a percentage and then applied to all samples.
t-testTrained ± SE)Untrained ± SETPdfAdults
2–3 weeksW85.7 ± 18.8538.25 ± 8.42−1.600.2601.85
6 monthsP1.3 ± 0.301.86 ± 0.41−2.140.1004
11 monthsP2.0 ± 0.451.58 ± 0.35−0.650.5544
Juveniles
6 monthsP0.2 ± 0.040.36 ± 0.07−1.220.2914
11 monthsP1.3 ± 0.281.06 ± 0.21−0.670.5424
All rainbowfish
6 monthsP1.5 ± 0.442.22 ± 0.49−2.880.0454
11 monthsP3.1 ± 0.622.97 ± 0.590.110.9204
FIGURE 2
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Abundance of released Running River rainbowfish over time during the first field season in Deception Creek for trained and untrained fish. Different markers represent different release sites. Note, the number of released fish cannot increase, as fish were only released once into each site.Regression analysis found no significant link between predator density and RRR abundance or density for any survey season (Table 2). This was the case even when the analysis was broken up into different size classes for both RRR and spangled perch. Although these results were not statistically significant, there was a positive correlation between adult RRR density and the density of all spangled perch (Appendix S1).
TABLE 2. Statistical output from linear regression analysis testing predator density as a predictor of rainbowfish abundance in the first month, and density at 6 and 11 months after release.
TPRdf2–3 weeks0.5270.621−0.1375
6 months−0.0140.989−0.1258
11 months1.5450.1610.1338Fry of RRR were detected within the first field season at four sites (two trained and two untrained) 30–40 days after release. In May 2017, both juveniles and adults that were too small to have been the released fish were detected at all sites. When the total density of RRR – including fry and juveniles – was compared, untrained release sites had significantly higher densities than trained release sites at 6 months after release, but at no other time (Table 1). No significant difference in RRR density was found between releases that took place before or after the flooding that occurred between the May (t = −1.91, P = 0.09) and October (t = 0.557, P = 0.59) surveys.
Unfortunately, only one survey of Puzzle Creek was made after release, as all other attempts were prevented by heavy rain and flooding. Flooding occurred between the release and the survey, and as a result the data from the Puzzle Creek survey were not analysed.
Anecdotal observations in Deception Creek made in the hours and days immediately after release suggest that there may have been some behavioural differences between trained and untrained fish. In both pre-flood releases, the trained fish shoaled together close to the point of release and found a shallow, sandy area out of the reach of larger spangled perch and remained there for around 6 days before dispersing more widely. In contrast, untrained fish were often observed swimming near the surface in open water and swimming towards the spangled perch, which were trying to eat them, before eventually finding shallow areas in which to hide.
3.4 DispersalWhen flooding occurred in Deception Creek the RRR moved between release sites, invalidating any comparisons between treatment pools. Ten days after flooding in Deception Creek, one individual RRR was recorded in an ephemeral gully stream 660 m upstream from Deception Creek and approximately 24 m higher in elevation than the nearest release site. The movements of fish from their uppermost and lowermost release sites in both systems are summarized in Table 3. The population in Deception Creek spread upstream and downstream much faster than the fish in Puzzle Creek (Table 3). In 1 year, RRR from Puzzle Creek dispersed a total of 460 m upstream, 200 m less than the distance covered by a fish from Deception Creek in 10 days. In Deception Creek there was a large increase in the distance spread downstream between October 2017 and April 2018 (Table 3). The maximum distance of spread downstream in Deception Creek in April 2018 could not be determined because of time constraints and limited access to that portion of the creek.
TABLE 3. Upstream and downstream movements of Running River rainbowfish from their release sites in Deception and Puzzle creeks over time.
Time since releaseDistance (elevation)
UpstreamDownstreamDeception Creek May 20176 months1.9 km (31 m)1.3 km (46 m)
Deception Creek October 201711 months2.4 km (39 m)2.7 km (62 m)
Deception Creek April 201817 months2.5 km (41 m)>6.3 km (>171 m)
Puzzle Creek May 201812 months0.46 km (9 m)1.33 km (30 m)4 DISCUSSION4.1 SummaryThis study documents efforts to conserve a Critically Endangered species threatened by the establishment of an alien species. This was achieved by translocating captive-bred offspring to two unoccupied creeks isolated by large waterfalls. The conservation actions to save the RRR were an outstanding success, given that they persist in the wild adjacent to their native range, and the research and monitoring accompanying the translocation releases aims to draw lessons on techniques and habitat selection for similar future projects. Additionally, it provides insights into the rate that rainbowfish may spread through a system.
4.2 Predator trainingAlthough the small sample sizes in this experiment meant that only major differences could be detected, the data presented here do not support the hypothesis that predator training (exposure to predators prior to release) or predation pressure influenced the introduction success in RRR. Although the only unsuccessful release was of untrained fish, all other releases of untrained fish were successful, suggesting that predator-naive fish are still capable of becoming established in the right circumstances. As rainbowfish are known to use social learning (Brown & Warburton, 1999b), and as experienced fish from other releases were observed at post-flood release sites, it is likely that post-flood releases were less affected by predation encounters than pre-flood releases. Introductions into Puzzle Creek were made during a high-flow event and yet still established a sustaining population, so it is likely that the post-flood releases in Deception Creek survived to reproduction. Few released fish, if any, were present at release sites 6 months later, as most fish observed were smaller than the individuals released, and thus it was likely that most of the fish observed were spawned in the wild. Therefore, owing to the high fecundity of rainbowfishes (Milton & Arthington, 1984; Pusey et al., 2001), differences in rainbowfish density would not be expected at 6 or 11 months after the releases. As the rainfall, flow regime, habitat, vegetation, and resident fish biota of Puzzle Creek were different from that of Deception Creek, and Puzzle Creek was only surveyed once, the conclusions that can be drawn from this translocation are limited. It can, however, be said that predation and competition with purple spotted gudgeon and flooding during introduction did not prevent RRR from becoming established.
Although unquantified, the anecdotal observations made in the hours and days immediately after the Deception Creek releases followed the findings of Brown & Warburton (1999a), where naive rainbowfish were less able to evade danger than experienced ones. One reason that predation may not have had a significant impact is that neither spangled perch nor purple spotted gudgeon are primarily piscivorous (Pusey, Kennard & Arthington, 2004). The presence of a more specialized piscivore, such as the mouth almighty (Glossamia aprion), might have produced a different outcome. The mouth almighty has been implicated in the extirpation of the Lake Eacham rainbowfish (M. eachamensis) from Lake Eacham (Barlow, Hogan & Rodger, 1987), and it is not unreasonable that a similarly proficient piscivore could have adverse impacts on an introduction of small-bodied fish if they did not possess the ability to recognize or escape predators (Brown & Warburton, 1997).
4.3 Translocation successThe RRR releases were an uncommon success for Australian freshwater fish conservation translocations, which could be explained by several factors that were likely to be working in unison. First, eggs were observed within the overnight instream holding pen at some sites before the fish were released the following morning. The use of well-conditioned, sexually mature fish under conditions favourable for spawning allows them to do so on the first day, which has obvious benefits when trying to establish a new population. Second, the fish were given a soft release (with a gradual transition from captivity to nature) to allow them to adjust to the water parameters of the receiving site and recover from handling or transport stress. It has been known for some time that handling and transport not only causes stress and in turn reduced survival rates in fishes, but that the effects can linger for some time afterwards (Hattingh, Le Roux Fourie & van Vuren, 1975; Iversen, Finstad & Nilssen, 1998). However, the approach is not commonly used in fish releases and may therefore be one area in which future fish releases could improve. This soft-release approach had the added effect of allowing fish to reproduce in a protected area for a short time.
4.4 DispersalAlthough there is a paucity of information regarding the movements of Australian small-bodied freshwater fishes, studies on ephemeral waterholes (Kerezsy et al., 2013) and genetics (Unmack, Allen & Johnson, 2013) suggest that some of these species are capable of dispersing great distances. The study of dispersal in small-bodied fishes has often been hampered by their size and the consequent limitations in employing individually tagged fish (Allan et al., 2018). However, these releases in a stream of low turbidity, where snorkelling could be used as a monitoring method, provided a unique opportunity to understand the rate at which rainbowfishes may spread throughout a previously unoccupied waterway. Puzzle Creek flows more frequently than Deception Creek, suggesting that expansion throughout Puzzle Creek could occur much faster. Although fewer fish were stocked into Puzzle Creek, the fecundity of the species should have counteracted any effect that this may have had on dispersal, meaning it was reasonable to assume that RRR would spread through Puzzle Creek at a similar if not faster rate. Contrary to what might have been expected, the RRR dispersed throughout Deception Creek faster than Puzzle Creek.
One possible explanation is that although the same number of fish per pool were released into Puzzle Creek, these pools were much larger and better connected than those in Deception Creek, resulting in lower densities of adult fish. This may have been exacerbated by flooding at the time of release, which may have encouraged dispersal. Some locations that fish dispersed to will not provide long-term habitat during dry periods, and it is almost certain that many fish died after dispersal in Deception Creek, as many individuals were observed occupying more temporary habitats (e.g. the individuals observed within the ephemeral gully). In Deception Creek, however, opportunities to disperse were less frequent and were initially limited, restricting released fish to their release sites where they increased in population size, thereby increasing the success of subsequent dispersal. The site fidelity of translocated individuals is consistently lower than that of wild individuals across most faunal groups (Clarke & Schedvin, 1997; Tuberville et al., 2005), including fish (Ebner & Thiem, 2009). Immediate dispersal from the point of release may increase the likelihood of translocation failure, as individuals may disperse to suboptimal habitats, encounter predators in unfamiliar environments, become so thinly distributed that Allee effects increase, and so forth. In some instances, ‘penning’, whereby translocated organisms are kept in pens at the release site for several days or weeks before being allowed to roam free, has been an effective method of increasing site fidelity and the overall success of establishment (Tuberville et al., 2005). It is possible that during periods of low flow, disconnected pools acted in a similar fashion, forcing fish to develop some site fidelity with their new habitat and allowing them to increase in number, thereby increasing the number of fish that dispersed when it became possible to do so.
4.5 Lessons learnedTranslocations are becoming an increasingly important conservation tool the world over, especially for small-bodied fishes. The findings of this study are discussed in the context of Australia; however, the issues faced here are likely to be relevant globally. Despite its importance in formulating effective conservation translocation plans, there are few studies incorporating robust follow-up monitoring on Australian native fish releases (Lintermans, 2013b) or survival in the weeks immediately after release. A recent review of threatened species monitoring in Australia found significant deficiencies for all vertebrate faunal groups (Scheele et al., 2019), as well as for freshwater fishes specifically (Lintermans & Robinson, 2018). In the present study, monitoring showed that the failed release had failed within 2 days of the release. External factors and small sample sizes that are typical of conservation translocations make it difficult to assess adequately the effect of predator training on post-release survival. Our anecdotal observations of different behaviours immediately after release suggest that this would be a fruitful area for further investigation (Berger-Tal, Blumstein & Swaisgood, 2020). Given the length of time required to examine long-term survival, we recommend that future studies focus on behavioural deficiencies occurring in the immediate period after release. Owing to its low cost and support from laboratory-based experiments (Vilhunen, 2006; Hutchison et al., 2012), we recommend the continued implementation of predator training in release programmes.
Anecdotal observations from successful releases indicated that the captive-reared fish introduced to Deception Creek gradually decreased in abundance over time. Natural processes such as predation and finding suitable resources, combined with the behavioural deficiencies of captive-reared fish, made such declines likely. However, upon release the fish were able to reproduce during periods of low flow and elevated temperatures, which are ideal spawning conditions for the other rainbowfish species in northern Queensland (Pusey et al., 2001), allowing the population to grow quickly and overcome initial declines. This suggests that the time of year that a release takes place may play an important role in determining whether or not it is successful. Owing to constraints on funding and time, it was not possible to obtain detailed information on the initial population growth for fish in Puzzle Creek in the first months after release. In contrast to Deception Creek, fish were released into Puzzle Creek at a time when conditions were not ideal for reproduction (e.g. with cooler temperatures, going into winter), and yet this still resulted in the successful establishment of a new population, highlighting that ideal conditions are not always necessary for establishment, at least in rainbowfishes.
Successful conservation introductions of Australian small-bodied freshwater fishes often take place in areas with no potential predators or competitors present, often to avoid non-native species that could prevent them from becoming established (Ayres, Nicol & Raadik, 2012; Chilcott et al., 2013). One of the main reasons for this is that predation or competition from alien species is often seen as a major cause of the decline of a species (Cadwallader, 1996; Lintermans, 2000; Morgan et al., 2003), and therefore conservation introductions are unlikely to succeed in locations where these alien predators or competitors are still present. Although negative interactions with alien species are the leading cause of decline in animal species globally (Clavero & García-Berthou, 2005; Bellard, Cassey & Blackburn, 2016; Allek et al., 2018), conservation introductions of RRR have shown that a complete lack of other species is not required. Studies on captive-reared fish have shown a rapid loss of behavioural traits, such as a loss of predator recognition (Alvarez & Nicieza, 2003) and a reduced competitive ability (Rhodes & Quinn, 1998), suggesting that the recovery or adequate conservation of a species will be detrimentally affected if the species is maintained away from all predators and competitors. We would suggest that when conservation introductions are required, and predation is not an overwhelming threat (e.g. when suitable shelter from predators is available), effort should be made to include a mix of predator-free and predator/competitor-present release sites or a staged release similar to that described by Robinson & Ward (2011).
Conservation translocations for RRR contrast with those of larger-bodied, long-lived species. Unlike releases for larger species (Minckley, 1995; Harig, Fausch & Young, 2000; Ebner, Johnston & Lintermans, 2009; Lintermans, 2013c), it was possible to determine whether or not these releases were successful over a much shorter time period, much like other small-bodied fish translocations (Minckley, 1995). This can probably be explained by two factors: first, the RRR were released into habitats free of the cause of decline (introgression/hybridization); and second, like most small-bodied species RRR reach maturity at a much younger age (e.g. 1 year in rainbowfish; Milton & Arthington, 1984), compared with large-bodied species (e.g. 3–4 years in the Macquarie perch, Macquaria australasica; Appleford, Anderson & Gooley, 1998). This means that released fish can reproduce in a relatively short period of time, so even if released fish exhibit behavioural deficiencies that inhibit long-term survival, wild-spawned fish free of these deficiencies will rapidly be present (Alvarez & Nicieza, 2003). However, it is also worth noting that a shorter lifespan poses an extra risk. Although it has already been noted that the conservation benefits of captive maintenance for a species may be limited (Philippart, 1995; Snyder et al., 1996; Araki, Cooper & Blouin, 2007; Attard et al., 2016), the short lifespans and generation times of most small-bodied species mean that the adverse effects of captive maintenance will take effect more quickly, and that stochastic events such as a reproductive failure can extinguish annual species rapidly.
This research has established two factors important for the continued management and conservation of small-bodied fish species: (i) that they may easily establish new populations when the dominant threat is removed and suitable habitat is available; and (ii) that conservation translocations for small-bodied fish species can be carried out on a moderately sized budget of AU$10,000–20,000. Most small-bodied species are less likely to be intentionally translocated outside their natural range, compared with large-bodied species (Rahel, 2004; Hunt & Jones, 2017), and are more likely to enter a new area through other pathways such as bait-bucket translocations and stocking contamination (Ludwig & Leitch, 1996; Lintermans, 2004; Rahel, 2004). Given the number of widespread species complexes of small-bodied species in Australia (Page, Sharma & Hughes, 2004; Hammer et al., 2007; Raadik, 2014; Hammer et al., 2019a), the chance of an accidental translocation resulting in establishment, hybridization, and subsequent introgression is quite high. However, the ease with which populations may be established is also beneficial for the establishment of refuge populations used for conservation, assuming suitable refuge habitat is available.
Rainbowfish species with broad distributions (e.g. the eastern rainbowfish and the western rainbowfish) possess many traits that allow them to establish new populations quickly, and as a result the number of rainbowfish species threatened by translocation is likely to increase in the future. Many small-bodied species in Australia are likely to face the same challenges. To date, Australia can claim that it has experienced very few freshwater fish extinctions, with the limited examples being of undescribed taxa (Unmack, 2001; Faulks, Gilligan & Beheregaray, 2010), but this is unlikely to remain the case in the future unless appropriate management measures are taken. To prevent future declines and extinctions, careful management and continued robust monitoring will be required. The establishment of conservation populations for small-bodied species should be more easily achieved, as they are easier to breed or translocate and have early maturity, but this effort requires a small but important investment of funds towards the conservation of smaller native fish.
ACKNOWLEDGEMENTSWe have been fortunate to draw on a wide variety of support to help make this project possible. First, none of this would have been possible without the incredible generosity from rainbowfish people around the world; the support from everyone for the crowdfunding portion of the project has been amazing. The non-profit Australian Wildlife Conservancy provided extensive access, accommodation, and assistance, which was essential; thanks specifically to Tim and Bree White, Eridani Mulder, and John Kanowski. In the race to save this fish from extinction, Diversity Arrays Technology, based at the University of Canberra, have provided all the genetic data on their fast track to provide information as quickly as possible. The project has benefited greatly from our research team examining broader rainbowfish systematic research: Keith Martin (who was the initial cause of all this, with his incessant poking around in nooks and crannies for interesting rainbowfishes), Mark Adams, and Gerry Allen. Many others provided valuable contributions. From the University of Canberra: Michael Jones, Rod Yeo, Arthur Georges, and Bernd Gruber. From James Cook University: Damien Burrows. From Flinders University: ‘Yuma’ Sandoval-Castillo. From Queensland Fisheries: Steven Brooks. Open access publishing facilitated by University of Canberra, as part of the Wiley - University of Canberra agreement via the Council of Australian University Librarians.
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RESEARCH ARTICLE
Open Access
Alternative conservation outcomes from aquatic fauna translocations: Losing and saving the Running River rainbowfish
Karl Moy, Jason Schaffer, Michael P. Hammer, Catherine R. M. Attard, Luciano B. Beheregaray, Richard Duncan, Mark Lintermans, Culum Brown, Peter J. Unmack
First published: 16 October 2023
https://doi.org/10.1002/aqc.4023
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- The translocation of species outside their natural range is a threat to aquatic biodiversity globally, especially freshwater fishes, as most are not only susceptible to predation and competition but readily hybridize with congeners.
- Running River rainbowfish (RRR, Melanotaenia sp.) is a narrow-ranged, small-bodied freshwater fish that recently became threatened and was subsequently listed as Critically Endangered, owing to introgressive hybridization and competition following the translocation of a congeneric species, the eastern rainbowfish (Melanotaenia splendida).
- To conserve RRR, wild fish were taken into captivity, genetically confirmed as pure representatives, and successfully bred. As the threat of introgression with translocated eastern rainbowfish could not be mitigated, a plan was devised to translocate captive raised RRR into unoccupied habitats within their native catchment, upstream of natural barriers. The translocation plan involved careful site selection and habitat assessment, predator training (exposure to predators prior to release), soft release (with a gradual transition from captivity to nature), and post-release monitoring, and this approach was ultimately successful.
- Two populations of RRR were established in two previously unoccupied streams above waterfalls with a combined stream length of 18 km. Post-release monitoring was affected by floods and low sample sizes, but suggested that predation and time of release are important factors to consider in similar conservation recovery programmes for small-bodied, short-lived fishes.
1 INTRODUCTIONThe translocation of alien species is a major threat to many ecosystems worldwide (Vitousek et al., 1997; Clavero & García-Berthou, 2005; Gallardo et al., 2016). Globally, the rate of translocations has been increasing (Seebens et al., 2017), with alien species currently present on every continent (Prins & Gordon, 2014). Although there has been considerable research examining the adverse effects of alien species (McNeely, 2001; Prins & Gordon, 2014), translocations can also be an effective tool for conservation and management (Minckley, 1995; Tuberville et al., 2005; IUCN/SSC, 2013). Translocation has become a key tool for conserving freshwater fishes, using both wild and captive-bred fishes (Minckley, 1995; Lintermans, 2013a; Lintermans et al., 2015). When referring to different types of conservation translocations, this article follows the definitions provided by the International Union for Conservation of Nature Species Survival Commission (IUCN/SSC, 2013).
Most early conservation translocations of fish have involved large-bodied threatened species that were often potential angling targets (Minckley & Deacon, 1991; Lintermans et al., 2015). However, the practice has also been applied to smaller threatened fishes (Minckley & Deacon, 1991; Hammer et al., 2013; Lintermans et al., 2015; Tatár et al., 2016). The continued existence of certain species, such as the Pedder galaxias (Galaxias pedderensis) is solely the result of conservation translocations (Chilcott et al., 2013), whereas the conservation status of several Critically Endangered species, such as the red-finned blue-eye (Scaturiginichthys vermeilipinnis; Kerezsy & Fensham, 2013) and several other galaxiid species (Koster, 2003; Hardie, Barmuta & White, 2006; Ayres, Nicol & Raadik, 2012) have benefited substantially from translocations.
A review of factors influencing the success of freshwater fish reintroductions reported that second to addressing the cause of initial decline, habitat-related factors were the greatest predictors of reintroduction success (Cochran-Biederman et al., 2015). The importance of suitable habitat in determining the success or failure of conservation introductions is echoed by studies of invasive fish species, which have found that if the habitat characteristics of the receiving environment are suitable then an invasion is likely to succeed, regardless of other factors (Moyle & Light, 1996a; Moyle & Light, 1996b; Harris, 2013). That an introduction is likely to fail in the absence of suitable habitat seems straightforward; however, some reintroductions may fail even in the presence of adequate habitat (Barlow, Hogan & Rodger, 1987; Leggett & Merrick, 1997).
Out of all failed conservation translocations of fish, 71% used captive-reared fish (Cochran-Biederman et al., 2015). Captive-reared fish are often raised under conditions that are vastly different from the environment into which they are released (Brown, Davidson & Laland, 2003). Consequently, captive-reared fish often exhibit behaviours that are detrimental to their survival in the wild, and as a result often suffer from high mortality rates once released (Brown & Day, 2002; Ebner, Thiem & Lintermans, 2007; Sparrevohn & Støttrup, 2007), which is a prevalent problem across fauna groups (Berger-Tal, Blumstein & Swaisgood, 2020). The behavioural impacts of captive rearing have been known for some time (Brown & Day, 2002), with captive-reared fish showing deficiencies in key behaviours such as predator recognition and avoidance (Alvarez & Nicieza, 2003; Ebner, Thiem & Lintermans, 2007) and foraging skills (Brown & Laland, 2002; Brown, Davidson & Laland, 2003). Studies on the success of conservation introductions of freshwater fishes within Australia (Ebner, Thiem & Lintermans, 2007; Ebner, Johnston & Lintermans, 2009; Brown et al., 2012) and abroad (Alvarez & Nicieza, 2003) suggest that predation and competition are likely to play a major role in translocation success. Brown, Davidson & Laland (2003) showed that environmental enrichment and exposure to live foods resulted in fish being better able to handle novel prey items. Meanwhile, several studies have shown that repeated exposure to predators, or their stimulus (e.g. scent or pictures), will improve the predator avoidance behaviours of captive-bred fish (Brown, 2003a; Vilhunen, 2006; Hutchison et al., 2012; Abudayah & Mathis, 2016). As a result, research and implementation of environmental enrichment and predator training of captive-reared fish is becoming more commonplace (Vilhunen, 2006; Hammer et al., 2012; Roberts et al., 2014; Lintermans et al., 2015).
Most research investigating methods to improve the survival of captive-reared fishes has taken place overseas, although some recent research has been conducted in Australia (Hutchison et al., 2012). In both cases, the research investigating introduction success has focused almost entirely on large-bodied, predatory, recreationally important species, such as brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) (Brown & Smith, 1998; Alvarez & Nicieza, 2003; Brockmark, Adriaenssens & Johnsson, 2010), or percichthyids (Ebner, Thiem & Lintermans, 2007; Ebner & Thiem, 2009; Hutchison et al., 2012). However, of the 17 Australian species used in conservation introductions documented by Lintermans et al. (2015), 10 were small-bodied species. Small-bodied species usually have vastly different requirements compared with large-bodied species, and a conservation measure that works well for large species may not be as effective for smaller species (e.g. growing them to a large size to prevent predation).
1.1 Study organism backgroundThe extinctions and declines of native fishes resulting from hybridization with alien species have been well documented throughout Europe and North America (Hitt et al., 2003; Rosenfield & Kodric-Brown, 2003; Meldgaard et al., 2007; Ludwig et al., 2009). Compared with other countries, introgressive hybridization with alien species has not typically been considered a threat to Australia’s native biodiversity (Hitt et al., 2003; Meldgaard et al., 2007; Ludwig et al., 2009) because most alien species have originated from other continents with biota that are taxonomically distant (Lintermans, 2013a). However, high levels of genetic structuring between populations as well as many new cryptic species were identified by recent broadscale genetic studies of Australian freshwater fishes (Hammer et al., 2007; Raadik, 2014; Shelley et al., 2018). Accordingly, introgressive hybridization caused by translocations of ‘native’ species outside their natural range, or from one part of a species range to another, has more recently been recognized as a threat to conservation for Australian freshwater fishes (Lintermans et al., 2005; Harris, 2013; Couch et al., 2016).
Endemic to Australia and New Guinea, the family Melanotaeniidae, or rainbowfishes, contains more than 110 species with multiple undescribed taxa (Unmack, Allen & Johnson, 2013). The genus Melanotaenia is by far the most numerous and widespread in Australia, occurring throughout the northern half of the continent and into south-eastern regions (Unmack, Allen & Johnson, 2013). There are several ‘lineages’ within the genus, and species within the same lineage rarely co-occur (Unmack, Allen & Johnson, 2013). In 2016, the Australian Society for Fish Biology (ASFB) listed four Melanotaenia species as Vulnerable, Endangered, or Critically Endangered, owing to introgressive hybridization with a widespread member of the genus (Lintermans, 2016), with a subsequent International Union for Conservation of Nature (IUCN) assessment confirming their threatened status (Hammer, Unmack & Brown, 2019b).
One of the species listed by the ASFB and the IUCN was the Running River rainbowfish (RRR Melanotaenia sp.). This species was first recorded in 1981 as a phenotypically unique population of rainbowfish from the usual native eastern rainbowfish (Melanotaenia splendida splendida) found in most rivers in the region (Martin & Barclay, 2016). Further collections across the region suggested that there was a complex of different rainbowfish populations, the taxonomy of which was unclear (Martin & Barclay, 2016). As part of a broader rainbowfish research project, fieldwork was conducted across the Burdekin River basin in August 2015 to try to resolve the taxonomic status of the various rainbowfish populations native to the region. During this fieldwork it was discovered that eastern rainbowfish had colonized the reach of Running River containing RRR, as well as being established in large numbers further upstream at Hidden Valley (Unmack & Hammer, 2015), an area previously lacking any rainbowfish (Martin & Barclay, 2016). It is unclear whether this represents a new translocation, or whether it represents downstream dispersal from earlier recorded translocated populations above Paluma Dam (although recent searches above Paluma Dam have failed to find any rainbowfish) (Martin & Barclay, 2016). Subsequent genetic and morphological examination supports the recognition of RRR as a separate species (P. Unmack, M. Hammer, G. Allen, unpublished data). As currently recognized, RRR is restricted to 13 km of Running River between two gorges (Figure 1). Running River is a major tributary to the Burdekin River, one of Australia’s larger river basins, situated on the north-eastern coast of Queensland (Pusey, Arthington & Read, 1998). The lower gorge prevents the upstream movement of eastern rainbowfish, whereas the upper gorge prevents the movement of RRR further upstream.
FIGURE 1
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Map of the study area showing the location of Puzzle and Deception creeks and their positions relative to Running River and its gorges. Purple arrows indicate the range of Running River rainbowfish, whereas orange arrows indicate the range of the eastern rainbowfish (Melanotaenia splendida). Created by AWC Spatial Officer Tani Cooper, and used with permission from the Australian Wildlife Conservancy.Once eastern rainbowfish had been detected in Running River above the upper gorge in 2015 it was realized that RRR was at risk of extinction via hybridization, as no members of the Australis lineage (Unmack, Allen & Johnson, 2013) of rainbowfishes are ever found in sympatry. At this point it was apparent that this population was distinct and worth conserving, but its taxonomic status would not be clear until genetic work had been conducted. Initially, 52 live wild fish were collected and then brought back to the University of Canberra as an insurance population. As this research lacked any formal funding, crowdfunding was initiated via the University of Canberra Foundation to cover the costs of genotyping potential broodstock, and keeping, breeding, and shipping the fish, and used internal University of Canberra funding to fund a postgraduate research project. Funds were sought by directly contacting various aquarium societies, primarily from North America, Australia, and Europe, as well as being solicited from members of the Australia New Guinea Fishes Association during presentations and in their journal Fishes of Sahul. In addition, we put out calls for donations via social media in various Australian native fish-related Facebook groups and in the aquarium magazine Amazonas. There is tremendous worldwide interest in rainbowfishes from aquarium hobbyists, as they are brightly coloured and easy to keep and breed. Many aquarium hobbyists, clubs, and businesses have a strong conservation ethos and are enthusiastic about supporting projects like ours by donating money. Once preliminary data on the taxonomy of rainbowfishes in the Burdekin River basin had been collected it became clear that RRR was a unique taxon from the Australis lineage and action was needed to save it.
The only conservation options available for RRR were either to hold the fish in captivity for the long term or to find locations where they could be translocated to, as it would take a massive effort to remove the eastern rainbowfish from upper Running River and then restore RRR in their native range. Maintaining the species in wild habitats was the most feasible option, thus the next challenge was to determine whether any suitable sites for translocation might exist.
The eastern rainbowfish is a capable disperser, occupying most habitats throughout its range, unless there are significant barriers to prevent movement, and thus finding habitats where it is absent is unusual. The region around Running River is seasonally arid and most small creeks in the region do not hold water permanently. The middle to lower section of Running River has two larger tributaries, Deception Creek and Puzzle Creek, which are located on Mount Zero–Taravale (Figure 1), covered by two pastoral leases owned and managed by the Australian Wildlife Conservancy (AWC, a not-for-profit conservation organization). Both creeks have sections that flow through gorges or rocky reaches that hold permanent water, and both were reported to have fishes of unknown species present (T. White, manager of the AWC Mount Zero–Taravale Sanctuary). Both creeks were sampled in February 2016, with Deception Creek having a large population of spangled perch (Leipotherapon unicolor), as well as a few purple spotted gudgeon (Mogurnda sp.), whereas Puzzle Creek had the same species, but the uppermost section above a waterfall only contained an abundant population of purple spotted gudgeon. Deception Creek flows into Running River below the lower gorge, with eastern rainbowfish native to its lower reaches. One medium-sized waterfall was located on Deception Creek approximately 12 km upstream from the confluence with Running River. Puzzle Creek flows into Running River in the middle of the upper gorge, which historically probably lacked rainbowfish; in addition, it has several major waterfalls of 10–20 m in height present along its course. As both creeks lacked rainbowfish they were considered suitable long-term translocation sites. This was an extraordinarily fortuitous situation given the lack of permanent streams in the area and the lack of eastern rainbowfish in both these streams. Any translocations into other rivers would have had impacts on native rainbowfish populations located in downstream reaches, whereas the eastern rainbowfish in lower Running River already had a potential influx of RRR from upstream.
As small-bodied freshwater fishes commonly have a high risk of extinction (Reynolds, Webb & Hawkins, 2005; Olden, Hogan & Zanden, 2007; Kopf, Shaw & Humphries, 2017; Lintermans et al., 2020), there is a need for a better understanding of the factors influencing, and methods for improving, the survival of captive-bred small-bodied freshwater fishes once released, to reduce the chance of failure. One example of this type of failure is the previous attempts to return Melanotaenia eachamensis (Lake Eacham rainbowfish) to Lake Eacham after they were extirpated owing to the introduction of other fishes (Barlow, Hogan & Rodger, 1987). A captive breeding programme was established (Barlow, Hogan & Rodger, 1987) that produced 3,000 fish, which were then released into the lake; however, subsequent surveys failed to detect any survivors (Brown et al., 2012). Subsequent research showed that captive rainbowfish can behave very differently from wild fish (Brown & Warburton, 1997; Brown & Warburton, 1999a; Kydd & Brown, 2009). This highlights the complexity that can be involved in obtaining successful reintroduction outcomes.
The main goals of the present study were to initiate a conservation programme for a recently recognized, undescribed, small-bodied rainbowfish, the Running River rainbowfish (RRR, Melanotaenia sp.). This was achieved through the design and implementation of a conservation strategy that used captive breeding and translocations to conserve the species and to evaluate the success of the strategy to inform future efforts. The study also documented the history of the species, the discovery of the translocation of eastern rainbowfish, and how crowdfunding was used to support the project. This article reports on the results of experiments conducted to examine the role of predator training on translocation success. However, these can be difficult to assess because of the limited replication, small sample sizes, and perturbations caused by weather events.
2 METHODS2.1 Captive breedingIn 2015, 52 RRR were collected from Running River and transported to the University of Canberra. Broodstock were genotyped using single nucleotide polymorphisms (SNPs) based on DNA from fin clips and compared with wild fish that had been collected and preserved in liquid nitrogen in 1997 (18 years earlier), to ensure genetic purity. These fish were set up as 26 breeding pairs and used as broodstock for Deception Creek releases. In February 2016 additional wild fish were collected, with 32 fish genotyped and added as broodstock for Puzzle Creek releases. Fish were spawned in 17 groups of two males and two females. Some breeding groups had extra individuals added such that half the breeding groups consisted of five, six, or seven individuals. From these 26 pairs the target was to produce 110 offspring from each breeding group to ensure that each group made an equal contribution to the next generation. A target of 260 offspring was set for the 17 breeding groups. Approximately 6,900 fish were produced at the University of Canberra, 2,700 in the first round of breeding for Deception Creek and 4,200 in the second round of breeding for Puzzle Creek. Eggs were collected on synthetic wool mops placed into breeding tanks. After 2 days of spawning, the mops were transferred to small fish tanks (40 × 20 × 20 cm) and the juvenile fish were raised for approximately 2 months before being transferred to larger tanks (91 × 35 × 45 cm). Breeding and rearing tanks had painted sides and bottom and a sponge filter. Larvae were started on a diet of live vinegar eels (Turbatrix aceti), and as they grew larger moved onto a diet of juvenile brine shrimp (Artemia sp.) over the course of about a week, together with commercial flake food.
Once large enough for transport, the fish were air-freighted to James Cook University (JCU) Townsville and distributed evenly into 10 outdoor rearing ponds (108 cm in diameter and 36 cm deep, 330 L) to grow out. At JCU, the fish were fed with commercially available flake food three times a day and a mixture of frozen brine shrimp and blood worms (Chironomidae) once a day. All rearing ponds contained several large river stones and plastic mesh 50 × 100 cm with holes of 2.5 cm in diameter, which was contorted into different shapes and added to provide cover. This was to encourage natural behaviours such as using cover to escape threats, establishing and holding territories, and foraging, which have previously been found to result in improved survival rates (Brown, Davidson & Laland, 2003; Roberts et al., 2014). Although there were differences in the shape and size of the rocks, all the ponds were arranged in a similar pattern.
2.2 Predator trainingRelease sites in Deception Creek were known to contain a potential predator, the spangled perch. To test the impact of predator training, half of the rearing ponds were exposed to an adult spangled perch of approximately 15 cm in length placed in a 25 × 25 cm ‘mesh box’ made from plastic 2.5-cm mesh within the outdoor pond. RRR were able to swim freely in and out of the mesh box. In addition to providing the predator, a cutaneous alarm cue was also provided, which is often released when the skin of a fish is damaged and can be used in associative learning (Brown, 2003b; Brown & Chivers, 2007; Abudayah & Mathis, 2016). To obtain this alarm cue one RRR was euthanized (with an overdose of clove oil) per week of training, crushed up, mixed with water, and sieved to remove larger fragments. This solution was then frozen in an ice-cube tray and one cube was added at the same time as the spangled perch in the hope that juvenile RRR would associate the olfactory cue of dead or injured conspecifics with the stimulus of a spangled perch. The spangled perch was left in the rearing pond for 15 min per day for 7 days immediately before the fish were released into the wild.
2.3 Release sitesDeception Creek, which flows into Running River just below the lowermost gorge, and Puzzle Creek, which flows into Running River just above the uppermost gorge, were identified as the best potential translocation sites (Figure 1). Both creeks contained barriers to the upstream dispersal of rainbowfish (Figure 1) and already had resident fish fauna, meaning that the potential impacts on invertebrates and frogs of introducing a new fish species was minimal. Throughout most of the year Deception Creek consists of disconnected pools without flow, whereas Puzzle Creek flows for most of the year but with reduced/disconnected pools during periods of low rainfall. Purple spotted gudgeon was found in both creeks, whereas spangled perch was found throughout Deception Creek and in reaches below the release sites in Puzzle Creek. Although both species have the potential to prey upon small fishes, spangled perch grows to a much larger size than purple spotted gudgeon and are more active hunters (Pusey, Kennard & Arthington, 2004). Therefore, as the predation pressure on small fishes in Deception Creek was likely to be higher than that in Puzzle Creek, releases into Deception Creek were used to assess the effect of predator training on translocation success.
In an attempt to isolate the effects of predator training, the release sites within Deception Creek were paired based on similarities between habitat variables, with one site randomly selected to receive trained fish and with the other site receiving untrained fish. Puzzle Creek release sites were also assessed, but owing to the lower number of accessible pools, habitat assessments were only used to identify suitable release sites. The habitat variables examined were pool length, average pool width, substrate composition, average depth, deepest point, and riparian cover. Pool length was measured from the uppermost water edge to the farthest downstream water edge. Average pool width was calculated by taking three measurements at 25%, 50%, and 75% of the total length of the pool using a tape measure. A transect comprising five sample points was taken along each width measurement at 0% (+25 cm), 25%, 50%, 75%, and 100% (−25 cm) of the channel width. At each sample point, depth, substrate composition, macrophyte cover, and leaf litter were measured. Macrophyte cover, substrate, and leaf litter were all considered independent of one another. Macrophyte cover was defined as all emergent and submerged vegetation within the quadrat. Riparian cover was defined as the percentage of the bank covered by vegetation. Riparian cover was estimated by eye to the nearest 5%, whereas depth was measured using a metal ruler. All other variables were measured using a 50 × 50 cm quadrat.
Release pools were paired based on similar size, riparian cover, and substrate, in that order, with one pool randomly assigned to trained or untrained fish. As there were limits to the number of fish that could be produced, the 2,500 that were bred were divided into groups of 250 for release. This number was chosen to balance the number of release sites against the number of fish in each release.
2.4 Release and monitoringTen releases of 250 fish were performed across 10 release sites in Deception Creek between 2 November 2016 and 13 January 2017. Releases were made in groups of 250 to provide five replicates of each treatment (trained and untrained), as grow-out facilities consisted of 10 ponds. At release, the fish were approximately 3 cm in total length, on average, but varied from approximately 2 to 5 cm. Deception Creek releases occurred once every week or so; however, there was no assigned order for which releases happened when, owing to logistical constraints regarding predator avoidance training. Fish were transported from rearing ponds at JCU to their release sites in 20-L plastic buckets. Buckets were filled to one-third full and water was dosed with sea salt at 2.6 g L−1 and API Stress Coat® (Mars Fishcare, Inc., Chalfont, PA, USA), dosed at 0.8 ml L−1. Fish were delivered to their release site on the same day as collection from the rearing ponds in all but one case, which was hampered by heavy rainfall. In this instance, fish were held in buckets for 2 days with a daily water change, before delivery to their release site. Fish were held instream at the release site overnight in a holding net with dimensions of 1 × 1 × 1 m made from shade cloth and polyvinyl chloride (PVC) pipe. This allowed the fish to acclimatize to water conditions without any predation pressure. The following day the fish were released into the pool by gently up-ending the holding net.
After release, snorkel surveys were used to estimate the abundance of spangled perch and RRR in each pool. Snorkel surveys were chosen as the survey method needed to be non-destructive and non-intrusive. A small pilot study was conducted early on, comparing the detection rates among snorkel surveys, bait traps, and baited remote underwater video; however, the latter two methods did not detect a single RRR (K. Moy, unpublished data). Owing to logistical constraints, surveys occurred somewhat opportunistically. However, at least one survey was undertaken in the first week following release and this was often followed by other surveys up to 56 days after release. Forty-one surveys across five untrained and two trained release sites were made between 2 November 2016 and 5 January 2017. A large rainfall event (over 200 ml across 4 days at the nearest rainfall gauge) occurred in early January 2017, which caused flooding and restored flow to the channel, reconnecting the release pools before the predator training experiment in Deception Creek could be completed. This prevented any survey data being collected for the final three releases, which were all of trained fish. Snorkel surveys consisted of three passes: along the left bank, then the right bank, and with a final pass down the centre of the pool. The researcher kept a steady pace to prevent any double counting of fish, and on a waterproof notepad recorded a tally of the total number seen as well as the maximum seen at any one time, with a separate count for larvae. Spangled perch were also recorded in this way to estimate predator density. Follow-up surveys were undertaken for all sites in Deception Creek in May and October 2017.
After the first field season, the extent of fish occurrence throughout each drainage was mapped by walking along the creek, upstream and downstream from the uppermost and lowermost pools, respectively, and stopping at each pool encountered for 5 min to observe the presence or absence of rainbowfish. If no rainbowfish were observed within 5 min, the researcher moved to a different region of the pool and continued to observe for a further 5 min. If no rainbowfish were observed, the next pool downstream or upstream was also checked. This was repeated until three pools in a row were found without rainbowfish. This was carried out for Deception Creek in May and October 2017 and in April 2018. An attempt was made to map the extent of RRR in Deception Creek after the large rainfall event in early January 2017, following the same protocol above, but was hampered by low visibility owing to the increased turbidity.
Four releases, each consisting of 375 untrained fish, were made into four sites across Puzzle Creek in May 2017 in the same manner as those made into Deception Creek. Although the fish released into Puzzle Creek were the same size as those released into Deception Creek, only 1,500 of the originally intended 4,000 fish were released because of attrition in the rearing ponds. Owing to funding and weather constraints on fieldwork, no monitoring was undertaken in the weeks immediately after release for the Puzzle Creek releases. The planned monitoring of Puzzle Creek in October 2017 was prevented by a large rainfall event, but a survey of all release sites following the same protocol described above took place in May 2018. Distribution mapping for Puzzle Creek took place in May 2018 following the same protocol used for Deception Creek. Research was conducted under the University of Canberra Animal Ethics Committee approval CEAE 16-03.
2.5 AnalysisTwo-sample Student’s t-tests were used to test for differences in abundance in Deception Creek following release for trained versus untrained fish sites, paired by habitat variables, whereas an independent-samples Student’s t-test was used to look for differences in density between releases made before and after flooding. For observations not made in the month immediately after release, measures of abundance from the surveys were converted into measures of density by dividing the abundance by the length of the pool. Two-sample Student’s t-tests were used to determine differences in density between trained and untrained release sites within Deception Creek from data collected during May and October (approximately 6 and 8 months from release).
3 RESULTS3.1 CrowdfundingA total of AU$26,465 was raised from donations made by individuals (AU$4,435), companies (AU$1,150), and aquarium clubs (AU$20,880), with donations received from Australia, USA, Canada, Switzerland, and Germany. The largest donation was AU$10,000 from the Aquarium Society of Victoria. Most donations from aquarium clubs were solicited through personal contacts. Without these funds the project would have been impossible and RRR would be close to extinction. Crowdfunding covered all of the DNA sequencing costs, fish food, and live fish shipping, which cost approximately AU$12,000 in total. The bulk of the remaining funds were used over subsequent years to continue monitoring the wild and translocated populations, including further genetic monitoring.
3.2 HabitatIn October 2016, release sites in Deception Creek varied between 100 and 280 m in length and between 8 and 14 m in width. The average depth varied between 42 and 113 cm, whereas the deepest points ranged from 1.65 to 3.00 m. Riparian cover ranged from 60% to 99%. Substrate was dominated by sand (45%–95%), followed by boulder (0%–26%), bedrock (0%–24%), and cobble (0%–17%). On average, aquatic plants (macrophytes and charophytes) covered approximately 40% of the substrate, whereas leaf litter covered approximately 25% of the substrate. Release sites within Puzzle Creek were between 150 and 265 m in length and between 9.9 and 22.4 m in width, with the average depth ranging between 84 and 125 cm, and with the deepest points ranging from 1.70 to 2.75 m. Riparian cover varied between 95% and 80%, whereas the average substrate was dominated by sand (40%–60%), followed by bedrock (3%–43%), cobble (7%–32%), and boulder (2%–7%). On average, aquatic macrophytes and charophytes covered 20% of the substrate, whereas leaf litter covered 20% of the substrate.
3.3 Predator effectsThere was no significant difference in abundance or density of adult fish between trained and untrained release sites at any point after release (Table 1). Of the seven releases in Deception Creek before flooding, fish failed to become established at only one site following the release of untrained fish. This site was surveyed five times from 2–31 days after release without a single RRR observed, and was similar to other sites in every way. At the remaining sites the abundance of released fish appeared to decline continuously over the 56-day monitoring period for both treatments at sites where samples were collected for more than 2 weeks following release (Figure 2). However, linear regression analysis did not provide statistical support for this decline (t = 0.27, P = 0.788), although this could have been the result of the low detection power caused by small sample sizes and variation in detectability. Increasing numbers of detected fish at some sites over the first few days after release (Figure 2) were probably the result of fish becoming more familiar with their new environment.
TABLE 1. Statistical output comparing trained and untrained releases of fish. A Welch’s t-test (W) compared the total observed abundance at 2–3 weeks from release, whereas a paired Student’s t-test (P) compared the density of adults at 6 and 11 months from release. The standard error (SE) was calculated from 11 abundance observations between two sites that all fell within 4 days of one another, converted to a percentage and then applied to all samples.
t-testTrained ± SE)Untrained ± SETPdfAdults
2–3 weeksW85.7 ± 18.8538.25 ± 8.42−1.600.2601.85
6 monthsP1.3 ± 0.301.86 ± 0.41−2.140.1004
11 monthsP2.0 ± 0.451.58 ± 0.35−0.650.5544
Juveniles
6 monthsP0.2 ± 0.040.36 ± 0.07−1.220.2914
11 monthsP1.3 ± 0.281.06 ± 0.21−0.670.5424
All rainbowfish
6 monthsP1.5 ± 0.442.22 ± 0.49−2.880.0454
11 monthsP3.1 ± 0.622.97 ± 0.590.110.9204
FIGURE 2
Open in figure viewerPowerPoint
Abundance of released Running River rainbowfish over time during the first field season in Deception Creek for trained and untrained fish. Different markers represent different release sites. Note, the number of released fish cannot increase, as fish were only released once into each site.Regression analysis found no significant link between predator density and RRR abundance or density for any survey season (Table 2). This was the case even when the analysis was broken up into different size classes for both RRR and spangled perch. Although these results were not statistically significant, there was a positive correlation between adult RRR density and the density of all spangled perch (Appendix S1).
TABLE 2. Statistical output from linear regression analysis testing predator density as a predictor of rainbowfish abundance in the first month, and density at 6 and 11 months after release.
TPRdf2–3 weeks0.5270.621−0.1375
6 months−0.0140.989−0.1258
11 months1.5450.1610.1338Fry of RRR were detected within the first field season at four sites (two trained and two untrained) 30–40 days after release. In May 2017, both juveniles and adults that were too small to have been the released fish were detected at all sites. When the total density of RRR – including fry and juveniles – was compared, untrained release sites had significantly higher densities than trained release sites at 6 months after release, but at no other time (Table 1). No significant difference in RRR density was found between releases that took place before or after the flooding that occurred between the May (t = −1.91, P = 0.09) and October (t = 0.557, P = 0.59) surveys.
Unfortunately, only one survey of Puzzle Creek was made after release, as all other attempts were prevented by heavy rain and flooding. Flooding occurred between the release and the survey, and as a result the data from the Puzzle Creek survey were not analysed.
Anecdotal observations in Deception Creek made in the hours and days immediately after release suggest that there may have been some behavioural differences between trained and untrained fish. In both pre-flood releases, the trained fish shoaled together close to the point of release and found a shallow, sandy area out of the reach of larger spangled perch and remained there for around 6 days before dispersing more widely. In contrast, untrained fish were often observed swimming near the surface in open water and swimming towards the spangled perch, which were trying to eat them, before eventually finding shallow areas in which to hide.
3.4 DispersalWhen flooding occurred in Deception Creek the RRR moved between release sites, invalidating any comparisons between treatment pools. Ten days after flooding in Deception Creek, one individual RRR was recorded in an ephemeral gully stream 660 m upstream from Deception Creek and approximately 24 m higher in elevation than the nearest release site. The movements of fish from their uppermost and lowermost release sites in both systems are summarized in Table 3. The population in Deception Creek spread upstream and downstream much faster than the fish in Puzzle Creek (Table 3). In 1 year, RRR from Puzzle Creek dispersed a total of 460 m upstream, 200 m less than the distance covered by a fish from Deception Creek in 10 days. In Deception Creek there was a large increase in the distance spread downstream between October 2017 and April 2018 (Table 3). The maximum distance of spread downstream in Deception Creek in April 2018 could not be determined because of time constraints and limited access to that portion of the creek.
TABLE 3. Upstream and downstream movements of Running River rainbowfish from their release sites in Deception and Puzzle creeks over time.
Time since releaseDistance (elevation)
UpstreamDownstreamDeception Creek May 20176 months1.9 km (31 m)1.3 km (46 m)
Deception Creek October 201711 months2.4 km (39 m)2.7 km (62 m)
Deception Creek April 201817 months2.5 km (41 m)>6.3 km (>171 m)
Puzzle Creek May 201812 months0.46 km (9 m)1.33 km (30 m)4 DISCUSSION4.1 SummaryThis study documents efforts to conserve a Critically Endangered species threatened by the establishment of an alien species. This was achieved by translocating captive-bred offspring to two unoccupied creeks isolated by large waterfalls. The conservation actions to save the RRR were an outstanding success, given that they persist in the wild adjacent to their native range, and the research and monitoring accompanying the translocation releases aims to draw lessons on techniques and habitat selection for similar future projects. Additionally, it provides insights into the rate that rainbowfish may spread through a system.
4.2 Predator trainingAlthough the small sample sizes in this experiment meant that only major differences could be detected, the data presented here do not support the hypothesis that predator training (exposure to predators prior to release) or predation pressure influenced the introduction success in RRR. Although the only unsuccessful release was of untrained fish, all other releases of untrained fish were successful, suggesting that predator-naive fish are still capable of becoming established in the right circumstances. As rainbowfish are known to use social learning (Brown & Warburton, 1999b), and as experienced fish from other releases were observed at post-flood release sites, it is likely that post-flood releases were less affected by predation encounters than pre-flood releases. Introductions into Puzzle Creek were made during a high-flow event and yet still established a sustaining population, so it is likely that the post-flood releases in Deception Creek survived to reproduction. Few released fish, if any, were present at release sites 6 months later, as most fish observed were smaller than the individuals released, and thus it was likely that most of the fish observed were spawned in the wild. Therefore, owing to the high fecundity of rainbowfishes (Milton & Arthington, 1984; Pusey et al., 2001), differences in rainbowfish density would not be expected at 6 or 11 months after the releases. As the rainfall, flow regime, habitat, vegetation, and resident fish biota of Puzzle Creek were different from that of Deception Creek, and Puzzle Creek was only surveyed once, the conclusions that can be drawn from this translocation are limited. It can, however, be said that predation and competition with purple spotted gudgeon and flooding during introduction did not prevent RRR from becoming established.
Although unquantified, the anecdotal observations made in the hours and days immediately after the Deception Creek releases followed the findings of Brown & Warburton (1999a), where naive rainbowfish were less able to evade danger than experienced ones. One reason that predation may not have had a significant impact is that neither spangled perch nor purple spotted gudgeon are primarily piscivorous (Pusey, Kennard & Arthington, 2004). The presence of a more specialized piscivore, such as the mouth almighty (Glossamia aprion), might have produced a different outcome. The mouth almighty has been implicated in the extirpation of the Lake Eacham rainbowfish (M. eachamensis) from Lake Eacham (Barlow, Hogan & Rodger, 1987), and it is not unreasonable that a similarly proficient piscivore could have adverse impacts on an introduction of small-bodied fish if they did not possess the ability to recognize or escape predators (Brown & Warburton, 1997).
4.3 Translocation successThe RRR releases were an uncommon success for Australian freshwater fish conservation translocations, which could be explained by several factors that were likely to be working in unison. First, eggs were observed within the overnight instream holding pen at some sites before the fish were released the following morning. The use of well-conditioned, sexually mature fish under conditions favourable for spawning allows them to do so on the first day, which has obvious benefits when trying to establish a new population. Second, the fish were given a soft release (with a gradual transition from captivity to nature) to allow them to adjust to the water parameters of the receiving site and recover from handling or transport stress. It has been known for some time that handling and transport not only causes stress and in turn reduced survival rates in fishes, but that the effects can linger for some time afterwards (Hattingh, Le Roux Fourie & van Vuren, 1975; Iversen, Finstad & Nilssen, 1998). However, the approach is not commonly used in fish releases and may therefore be one area in which future fish releases could improve. This soft-release approach had the added effect of allowing fish to reproduce in a protected area for a short time.
4.4 DispersalAlthough there is a paucity of information regarding the movements of Australian small-bodied freshwater fishes, studies on ephemeral waterholes (Kerezsy et al., 2013) and genetics (Unmack, Allen & Johnson, 2013) suggest that some of these species are capable of dispersing great distances. The study of dispersal in small-bodied fishes has often been hampered by their size and the consequent limitations in employing individually tagged fish (Allan et al., 2018). However, these releases in a stream of low turbidity, where snorkelling could be used as a monitoring method, provided a unique opportunity to understand the rate at which rainbowfishes may spread throughout a previously unoccupied waterway. Puzzle Creek flows more frequently than Deception Creek, suggesting that expansion throughout Puzzle Creek could occur much faster. Although fewer fish were stocked into Puzzle Creek, the fecundity of the species should have counteracted any effect that this may have had on dispersal, meaning it was reasonable to assume that RRR would spread through Puzzle Creek at a similar if not faster rate. Contrary to what might have been expected, the RRR dispersed throughout Deception Creek faster than Puzzle Creek.
One possible explanation is that although the same number of fish per pool were released into Puzzle Creek, these pools were much larger and better connected than those in Deception Creek, resulting in lower densities of adult fish. This may have been exacerbated by flooding at the time of release, which may have encouraged dispersal. Some locations that fish dispersed to will not provide long-term habitat during dry periods, and it is almost certain that many fish died after dispersal in Deception Creek, as many individuals were observed occupying more temporary habitats (e.g. the individuals observed within the ephemeral gully). In Deception Creek, however, opportunities to disperse were less frequent and were initially limited, restricting released fish to their release sites where they increased in population size, thereby increasing the success of subsequent dispersal. The site fidelity of translocated individuals is consistently lower than that of wild individuals across most faunal groups (Clarke & Schedvin, 1997; Tuberville et al., 2005), including fish (Ebner & Thiem, 2009). Immediate dispersal from the point of release may increase the likelihood of translocation failure, as individuals may disperse to suboptimal habitats, encounter predators in unfamiliar environments, become so thinly distributed that Allee effects increase, and so forth. In some instances, ‘penning’, whereby translocated organisms are kept in pens at the release site for several days or weeks before being allowed to roam free, has been an effective method of increasing site fidelity and the overall success of establishment (Tuberville et al., 2005). It is possible that during periods of low flow, disconnected pools acted in a similar fashion, forcing fish to develop some site fidelity with their new habitat and allowing them to increase in number, thereby increasing the number of fish that dispersed when it became possible to do so.
4.5 Lessons learnedTranslocations are becoming an increasingly important conservation tool the world over, especially for small-bodied fishes. The findings of this study are discussed in the context of Australia; however, the issues faced here are likely to be relevant globally. Despite its importance in formulating effective conservation translocation plans, there are few studies incorporating robust follow-up monitoring on Australian native fish releases (Lintermans, 2013b) or survival in the weeks immediately after release. A recent review of threatened species monitoring in Australia found significant deficiencies for all vertebrate faunal groups (Scheele et al., 2019), as well as for freshwater fishes specifically (Lintermans & Robinson, 2018). In the present study, monitoring showed that the failed release had failed within 2 days of the release. External factors and small sample sizes that are typical of conservation translocations make it difficult to assess adequately the effect of predator training on post-release survival. Our anecdotal observations of different behaviours immediately after release suggest that this would be a fruitful area for further investigation (Berger-Tal, Blumstein & Swaisgood, 2020). Given the length of time required to examine long-term survival, we recommend that future studies focus on behavioural deficiencies occurring in the immediate period after release. Owing to its low cost and support from laboratory-based experiments (Vilhunen, 2006; Hutchison et al., 2012), we recommend the continued implementation of predator training in release programmes.
Anecdotal observations from successful releases indicated that the captive-reared fish introduced to Deception Creek gradually decreased in abundance over time. Natural processes such as predation and finding suitable resources, combined with the behavioural deficiencies of captive-reared fish, made such declines likely. However, upon release the fish were able to reproduce during periods of low flow and elevated temperatures, which are ideal spawning conditions for the other rainbowfish species in northern Queensland (Pusey et al., 2001), allowing the population to grow quickly and overcome initial declines. This suggests that the time of year that a release takes place may play an important role in determining whether or not it is successful. Owing to constraints on funding and time, it was not possible to obtain detailed information on the initial population growth for fish in Puzzle Creek in the first months after release. In contrast to Deception Creek, fish were released into Puzzle Creek at a time when conditions were not ideal for reproduction (e.g. with cooler temperatures, going into winter), and yet this still resulted in the successful establishment of a new population, highlighting that ideal conditions are not always necessary for establishment, at least in rainbowfishes.
Successful conservation introductions of Australian small-bodied freshwater fishes often take place in areas with no potential predators or competitors present, often to avoid non-native species that could prevent them from becoming established (Ayres, Nicol & Raadik, 2012; Chilcott et al., 2013). One of the main reasons for this is that predation or competition from alien species is often seen as a major cause of the decline of a species (Cadwallader, 1996; Lintermans, 2000; Morgan et al., 2003), and therefore conservation introductions are unlikely to succeed in locations where these alien predators or competitors are still present. Although negative interactions with alien species are the leading cause of decline in animal species globally (Clavero & García-Berthou, 2005; Bellard, Cassey & Blackburn, 2016; Allek et al., 2018), conservation introductions of RRR have shown that a complete lack of other species is not required. Studies on captive-reared fish have shown a rapid loss of behavioural traits, such as a loss of predator recognition (Alvarez & Nicieza, 2003) and a reduced competitive ability (Rhodes & Quinn, 1998), suggesting that the recovery or adequate conservation of a species will be detrimentally affected if the species is maintained away from all predators and competitors. We would suggest that when conservation introductions are required, and predation is not an overwhelming threat (e.g. when suitable shelter from predators is available), effort should be made to include a mix of predator-free and predator/competitor-present release sites or a staged release similar to that described by Robinson & Ward (2011).
Conservation translocations for RRR contrast with those of larger-bodied, long-lived species. Unlike releases for larger species (Minckley, 1995; Harig, Fausch & Young, 2000; Ebner, Johnston & Lintermans, 2009; Lintermans, 2013c), it was possible to determine whether or not these releases were successful over a much shorter time period, much like other small-bodied fish translocations (Minckley, 1995). This can probably be explained by two factors: first, the RRR were released into habitats free of the cause of decline (introgression/hybridization); and second, like most small-bodied species RRR reach maturity at a much younger age (e.g. 1 year in rainbowfish; Milton & Arthington, 1984), compared with large-bodied species (e.g. 3–4 years in the Macquarie perch, Macquaria australasica; Appleford, Anderson & Gooley, 1998). This means that released fish can reproduce in a relatively short period of time, so even if released fish exhibit behavioural deficiencies that inhibit long-term survival, wild-spawned fish free of these deficiencies will rapidly be present (Alvarez & Nicieza, 2003). However, it is also worth noting that a shorter lifespan poses an extra risk. Although it has already been noted that the conservation benefits of captive maintenance for a species may be limited (Philippart, 1995; Snyder et al., 1996; Araki, Cooper & Blouin, 2007; Attard et al., 2016), the short lifespans and generation times of most small-bodied species mean that the adverse effects of captive maintenance will take effect more quickly, and that stochastic events such as a reproductive failure can extinguish annual species rapidly.
This research has established two factors important for the continued management and conservation of small-bodied fish species: (i) that they may easily establish new populations when the dominant threat is removed and suitable habitat is available; and (ii) that conservation translocations for small-bodied fish species can be carried out on a moderately sized budget of AU$10,000–20,000. Most small-bodied species are less likely to be intentionally translocated outside their natural range, compared with large-bodied species (Rahel, 2004; Hunt & Jones, 2017), and are more likely to enter a new area through other pathways such as bait-bucket translocations and stocking contamination (Ludwig & Leitch, 1996; Lintermans, 2004; Rahel, 2004). Given the number of widespread species complexes of small-bodied species in Australia (Page, Sharma & Hughes, 2004; Hammer et al., 2007; Raadik, 2014; Hammer et al., 2019a), the chance of an accidental translocation resulting in establishment, hybridization, and subsequent introgression is quite high. However, the ease with which populations may be established is also beneficial for the establishment of refuge populations used for conservation, assuming suitable refuge habitat is available.
Rainbowfish species with broad distributions (e.g. the eastern rainbowfish and the western rainbowfish) possess many traits that allow them to establish new populations quickly, and as a result the number of rainbowfish species threatened by translocation is likely to increase in the future. Many small-bodied species in Australia are likely to face the same challenges. To date, Australia can claim that it has experienced very few freshwater fish extinctions, with the limited examples being of undescribed taxa (Unmack, 2001; Faulks, Gilligan & Beheregaray, 2010), but this is unlikely to remain the case in the future unless appropriate management measures are taken. To prevent future declines and extinctions, careful management and continued robust monitoring will be required. The establishment of conservation populations for small-bodied species should be more easily achieved, as they are easier to breed or translocate and have early maturity, but this effort requires a small but important investment of funds towards the conservation of smaller native fish.
ACKNOWLEDGEMENTSWe have been fortunate to draw on a wide variety of support to help make this project possible. First, none of this would have been possible without the incredible generosity from rainbowfish people around the world; the support from everyone for the crowdfunding portion of the project has been amazing. The non-profit Australian Wildlife Conservancy provided extensive access, accommodation, and assistance, which was essential; thanks specifically to Tim and Bree White, Eridani Mulder, and John Kanowski. In the race to save this fish from extinction, Diversity Arrays Technology, based at the University of Canberra, have provided all the genetic data on their fast track to provide information as quickly as possible. The project has benefited greatly from our research team examining broader rainbowfish systematic research: Keith Martin (who was the initial cause of all this, with his incessant poking around in nooks and crannies for interesting rainbowfishes), Mark Adams, and Gerry Allen. Many others provided valuable contributions. From the University of Canberra: Michael Jones, Rod Yeo, Arthur Georges, and Bernd Gruber. From James Cook University: Damien Burrows. From Flinders University: ‘Yuma’ Sandoval-Castillo. From Queensland Fisheries: Steven Brooks. Open access publishing facilitated by University of Canberra, as part of the Wiley - University of Canberra agreement via the Council of Australian University Librarians.
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Rineloricaria cachivera • A New Species of rheophilic Armored Catfish of Rineloricaria (Siluriformes: Loricariidae) from the Vaupés River, Amazonas Basin, Colombia
Rineloricaria cachivera
Urbano-Bonilla, Londoño-Burbano & Carvalho, 2023
DOI: 10.1111/jfb.15500
Abstract
A new rheophilic species of the genus Rineloricaria is described for the Amazon basin in Colombia. Rineloricaria cachivera n. sp. differs from its congeners by having anterior to the first predorsal plate, an inconspicuous saddle-like mark; the presence of dark, diffuse blotches, present as unified dark colouration along most of the dorsal portion of the head, without bands or spots on the head; a long snout that occupies more than half the head length (HL), between 58.0% and 66.3% HL; a naked portion on the cleithral area from the border of lower lip reaching the origin of pectoral fin; and by having five series of lateral plates in longitudinal rows below the dorsal fin. The new species is morphologically similar to Rineloricaria daraha; however, it can be distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long finger papillae). An identification key to the Rineloricaria species of the Amazon River basin in Colombia is provided. The new species is herein categorized as Least Concern, following the IUCN criteria.
Keywords: endemism, Loricariinae, river, rapids, species, diversity, taxonomy
Paratypes of Rineloricaria cachivera n. sp.
(a) Unpreserved specimen, río Vaupés at Resguardo Trubón. (b-c) MPUJ 14481, 114.4 mm standard length (LS), río Vaupés at Laguna Arcoiris small rocky bottom isolated lagoon from the river, Comunidad de Matapí, Mitú, Vaupés, Colombia.
Habitat of Rineloricaria cachivera n. sp.
(a) Tapira-Llerao sacred rock, (b) Raudal the Tapira-Llerao (Holotype) upstream of the Matapi indigenous community, (c) Laguna Arcoiris “small lagoon isolated from the raudal La Mojarra (paratype) upstream from the indigenous community of Matapi, (d) Raudal in the indigenous community of Trubón (paratype), and (e, f) petroglyphs in the cachiveras of the Vaupés River “Sacred sites” upstream of the Matapí indigenous community.
Rineloricaria cachivera new species
Etymology: The specific name cachivera refers to a flow of water that runs violently between the rocks. In the cosmology of the indigenous peoples of the Vaupés, the waters of its rivers are inhabited by various supernatural creatures that must be venerated, consulted, and appeased in the rituals of the shamans; these creatures live and guard mainly the cachiveras of the rivers where humans are more fragile and face the greatest danger (Schultes & Raffauf, 2004) (e.g., Figure 4e,f). The species was named in memory of Javier Alejandro Maldonado-Ocampo “Nano,” who collected the new species in the cachivera of “Trubón” and “La Mojarra”; in the latter, on March 2, 2019, Nano stayed forever swimming in peace and happy with the rheophilic fish of the cachiveras of the Vaupés River.
Alexander Urbano-Bonilla, Alejandro Londoño-Burbano and Tiago P. Carvalho. 2023. A New Species of rheophilic Armored Catfish of Rineloricaria (Siluriformes: Loricariidae) from the Vaupés River, Amazonas Basin, Colombia. Journal of Fish Biology. DOI: 10.1111/jfb.15500
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Rineloricaria cachivera
Urbano-Bonilla, Londoño-Burbano & Carvalho, 2023
DOI: 10.1111/jfb.15500
Abstract
A new rheophilic species of the genus Rineloricaria is described for the Amazon basin in Colombia. Rineloricaria cachivera n. sp. differs from its congeners by having anterior to the first predorsal plate, an inconspicuous saddle-like mark; the presence of dark, diffuse blotches, present as unified dark colouration along most of the dorsal portion of the head, without bands or spots on the head; a long snout that occupies more than half the head length (HL), between 58.0% and 66.3% HL; a naked portion on the cleithral area from the border of lower lip reaching the origin of pectoral fin; and by having five series of lateral plates in longitudinal rows below the dorsal fin. The new species is morphologically similar to Rineloricaria daraha; however, it can be distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long finger papillae). An identification key to the Rineloricaria species of the Amazon River basin in Colombia is provided. The new species is herein categorized as Least Concern, following the IUCN criteria.
Keywords: endemism, Loricariinae, river, rapids, species, diversity, taxonomy
Paratypes of Rineloricaria cachivera n. sp.
(a) Unpreserved specimen, río Vaupés at Resguardo Trubón. (b-c) MPUJ 14481, 114.4 mm standard length (LS), río Vaupés at Laguna Arcoiris small rocky bottom isolated lagoon from the river, Comunidad de Matapí, Mitú, Vaupés, Colombia.
Habitat of Rineloricaria cachivera n. sp.
(a) Tapira-Llerao sacred rock, (b) Raudal the Tapira-Llerao (Holotype) upstream of the Matapi indigenous community, (c) Laguna Arcoiris “small lagoon isolated from the raudal La Mojarra (paratype) upstream from the indigenous community of Matapi, (d) Raudal in the indigenous community of Trubón (paratype), and (e, f) petroglyphs in the cachiveras of the Vaupés River “Sacred sites” upstream of the Matapí indigenous community.
Rineloricaria cachivera new species
Etymology: The specific name cachivera refers to a flow of water that runs violently between the rocks. In the cosmology of the indigenous peoples of the Vaupés, the waters of its rivers are inhabited by various supernatural creatures that must be venerated, consulted, and appeased in the rituals of the shamans; these creatures live and guard mainly the cachiveras of the rivers where humans are more fragile and face the greatest danger (Schultes & Raffauf, 2004) (e.g., Figure 4e,f). The species was named in memory of Javier Alejandro Maldonado-Ocampo “Nano,” who collected the new species in the cachivera of “Trubón” and “La Mojarra”; in the latter, on March 2, 2019, Nano stayed forever swimming in peace and happy with the rheophilic fish of the cachiveras of the Vaupés River.
Alexander Urbano-Bonilla, Alejandro Londoño-Burbano and Tiago P. Carvalho. 2023. A New Species of rheophilic Armored Catfish of Rineloricaria (Siluriformes: Loricariidae) from the Vaupés River, Amazonas Basin, Colombia. Journal of Fish Biology. DOI: 10.1111/jfb.15500
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Opistognathus ctenion (Perciformes, Opistognathidae): a new jawfish from southern Japan
Kyoji Fujiwara, Hiroyuki Motomura, Gento ShinoharaAbstractOpistognathus ctenion sp. nov. (Perciformes: Opistognathidae) is described on the basis of three specimens (17.3–30.6 mm in standard length) collected from the Osumi and Ryukyu islands, southern Japan in depths of 35–57 m. Although most similar to Opistognathus triops, recently described from Tonga and Vanuatu, the new species differs in mandibular pore arrangement, dorsal- and caudal-fin coloration, fewer gill rakers, and lacks blotches or stripes on the snout, suborbital region and both jaws.
Key wordsActinopterygii, dredge, new species, Osumi Islands, Ryukyu Islands, taxonomy
IntroductionOpistognathus Cuvier, 1816 is the most speciose genus of jawfishes (Perciformes: Opistognathidae), being distributed worldwide in tropical and temperate regions, except for the eastern Atlantic Ocean and Mediterranean Sea (Smith-Vaniz 2023); most species of Opistognathus occur in the Indo-West Pacific. A recent review of the genus by Smith-Vaniz (2023) recognized 60 valid species, 18 being new, and additional new species of Opistognathus were predicted. To date, valid species of Opistognathus total 91 overall (Smith-Vaniz 2023).
Examination of specimens in the Kagoshima University Museum, Japan (KAUM) and the National Museum of Nature and Science, Japan (NSMT) revealed an unidentified species of Opistognathus, collected in 35–57 m depth off the Osumi and Ryukyu islands, southern Japan. In common with the majority of species of Opistognathus, the number of known examples of the present species is small, due to difficulties in collecting, attributed to their small body size and cryptic habitat [for details see Smith-Vaniz (2023)]. Notwithstanding, the species is clearly distinct, having a unique combination of meristic characters and fresh coloration, and is here formally described as a new to science.
Material and methodsMorphological observationCounts and measurements followed Smith-Vaniz (2023). Standard length (SL) was measured to the nearest 0.1 mm. Other measurements were made to the nearest 0.01 mm using needle-point calipers under a dissecting microscope (ZEISS Stemi DV4). Counts of vertebrae and fin rays, plus dorsal- and anal-fin pterygiophores, were examined from radiographs. Further osteological characters were investigated by computed tomography (CT) scanning using inspeXio SMX-225CR FPD HR Plus (Shimadzu, Kyoto) at 100 kV and 120 μA at a resolution of 18 μm, and three-dimensional reconstruction images produced by the rendering software VGSTUDIO MAX ver. 3.3 (Volume Graphics, Nagoya).
Preparation of figuresPhotographs of preserved specimens were taken with a Nikon D850 camera using an internal focus bracketing function; sets of multifocal images were then collated into a composite image, using Adobe Photoshop. The distribution map was prepared using GMT ver. 5.3.1, with data from GSHHG (Wessel and Smith 1996). The names and grouping of islands in southern Japan (belonging to Kagoshima and Okinawa prefectures) follow Motomura and Matsunuma (2022: fig. 5.2).
Comparative dataMorphological characters of comparative species of Opistognathus are cited from Smith-Vaniz (2023).
Results and discussion Opistognathus ctenion sp. nov.https://zoobank.org/66D79DFB-6CAA-4E18-A766-B2F117333C13
Figs 1, 2, 3, 4, 5, 6; Table 1 New English name: Japanese Whitespotted Jawfish New standard Japanese name: Shiratama-agoamadaiType materialHolotype. KAUM–I. 174226, 30.6 mm SL, off Mage-shima Island, Osumi Islands, Kagoshima, Japan, 35 m depth, dredge, 29 Sept. 2022, K. Kubota. Paratypes. KAUM–I. 174227, 26.2 mm SL, collected with holotype; NSMT-P 130174, 17.3 mm SL, southwest of Nagannu Island, Kerama Islands, southern Ryukyu Islands, Okinawa, Japan (26°14′33"N, 127°31′19"E–26°14′30"N, 127°31′24"E), 53–57 m depth, dredge operated by R/V Toyoshio-maru (Hiroshima University), 19 May 2017, G. Shinohara.
DiagnosisA species of Opistognathus distinguished from congeners by the following combination of characters: posterior end of upper jaw rigid, without flexible lamina; dorsal-fin rays XI, 16–18; anterior dorsal-fin spines very stout and straight, and their distal ends not transversely forked; anal-fin rays II, 17; gill rakers 6 or 7 + 13 or 14 = 20 or 21; vertebrae 10 + 22 = 32; longitudinal scale rows c. 40–50; lateral line terminating below 4th–6th soft ray of dorsal fin; 4th and 5th mandibular pore positions usually included 2 and 6–7 pores, respectively; body scales absent anterior to vertical below 4th or 5th dorsal-fin spine; vomerine teeth 2; body reddish-brown with 3 or 4 longitudinal rows of c. 8–10 whitish blotches; cheek and opercle with five or six whitish blotches; snout, suborbital region, and both jaws without blotches or stripes; spinous dorsal fin with ocellus between 2nd to 5th spines; dorsal-fin soft-rayed portion with two reddish-orange stripes; pectoral-fin base with one or two whitish blotches; caudal fin uniformly faint orange or reddish-yellow.
DescriptionGeneral appearance of type specimens as in Figs 1, 2 and 3. Lateral line system and osteological features of the holotype are given in Figs 4 and 5, respectively. Lateral line system and scale descriptions based on KAUM–I. 174226, 174227 (not available for NSMT-P 130174 due to poor specimen condition). Counts and measurements of type specimens are given in Table 1.
Table 1.
Download as
CSV
XLSXCounts and measurements of Opistognathus ctenion.
HolotypeParatypeParatype
KAUM–I. 174226KAUM–I. 174227NSMT-P 130174
Standard length (mm; SL)30.626.217.3
Counts
Dorsal-fin raysXI, 16XI, 18XI, 18
Anal-fin raysII, 17II, 17II, 17
Total pectoral-fin rays19 (left) / 19 (right)19 / 1919 / –
Pelvic-fin raysI, 5I, 5I, 5
Procurrent caudal-fin rays5 + 55 + 5–
Branched caudal-fin rays12––
Segmented caudal-fin rays8 + 8 = 168 + 8 = 168 + 8 = 16
Longitudinal scale rowsc. 40–50c. 40–50–
Vertebrae10 + 22 = 3210 + 22 = 3210 + 22 = 32
Gill rakers7 + 13 / 7 + 14 = 20 / 216 + 14 / 6 + 14 = 20 / 20– / 7 + 14 = 21
Measurements (% SL)
Pre-dorsal-fin length32.332.535.1
Pre-anal-fin length63.359.765.1
Dorsal-fin base length62.963.559.8
Anal-fin base length34.337.034.2
Pelvic-fin length22.621.121.7
Caudal-fin length20.923.222.2
Body depth15.316.010.3
Caudal-peduncle depth7.98.06.5
Head length32.331.934.3
Postorbital length19.820.519.1
Upper-jaw length17.417.217.4
Postorbital-jaw length6.85.54.3
Orbit diameter10.010.511.2
As % of head length
Postorbital length61.364.255.6
Upper-jaw length53.953.850.8
Postorbital-jaw length21.217.312.5
Orbit diameter30.932.832.7– indicates no data due to poor condition.
Figure 1. Holotype of Opistognathus ctenion (KAUM–I. 174226, 30.6 mm SL, off Mage-shima island, Osumi Islands, Kagoshima, Japan) A fresh and B preserved specimens photographed by KAUM and K. Fujiwara, respectively C X-ray image, photographed by K. Fujiwara.
Figure 2. Fresh coloration of two paratypes (A, C KAUM–I. 174226, 30.6 mm SL B, D KAUM–I. 174227, 26.2 mm SL) of Opistognathus ctenion, photographed by KAUM A, B lateral views C, D dorsal views.
Figure 3. Small paratype of Opistognathus ctenion (NSMT-P 130174, 17.3 mm SL) A fresh and B preserved specimens, photographed by G. Shinohara and K. Fujiwara, respectively.
Figure 4. Head of holotype of Opistognathus ctenion (KAUM–I. 174226, 30.6 mm SL), showing cephalic sensory pores (left column cyanine blue stain; right column solid yellow). Photographed by K. Fujiwara.
Figure 5. Three-dimensional reconstruction of head and anterior body in Opistognathus ctenion (KAUM–I. 174226, 30.6 mm SL), based on CT scanning. Photographed by G. Shinohara and K. Fujiwara. Abbreviations: ACh, anterior ceratohyal; Ana, anguloarticular; Bh, basihyal; Br, branchiostegal rays; Bsph, basisphenoid; Cl, cleithrum; Cor, coracoid; De, dentary; DHh, dorsal hypohyal; DPcl, dorsal postcleithrum; Ect, ectopterygoid; Ent, entopterygoid; Epoc, epiotic; Exoc, exoccipital; Fr, frontal; Hy, hyomandibular; Ih, interhyal, IO1 to IO5, 1st to 5th infraorbitals, respectively; Iop, interopercle; LE, lateral ethmoid; Met, metapterygoid; Mx, maxilla; Na, nasal; Op, opercle; Pa, parietal; Pal, palatine; PecR, pectoral radial; Pmx, premaxilla; Pop, preopercle; Psph, parasphenoid; Pt, posttemporal; Pte, pterotic; Q, quadrate; Ra, retroarticular; Sc, scapula; Scl, supracleithrum; Smx, supramaxilla; Soc, supraoccipital; Sop, subopercle; Sph, sphenotic; Ste, supratemporal; Sym, symplectic; Ur, urohyal; V1, 1st vertebral centrum; Vo, vomer; and VPcl, ventral postcleithrum. Asterisks indicate poorly resolved features.
Head and body. Body elongate, compressed anteriorly, progressively more compressed posteriorly. Anus situated just before anal-fin origin. Head cylindrical, its profile rounded. Eyes somewhat large, located dorsolaterally. Anterior nostril a short membranous tube with a tiny tentacle on posterior rim, when depressed not reaching posterior nostril; situated about mid-way between posterior nostril and dorsal margin of upper lip. Posterior nostril opening elliptical. Mouth terminal, obliquely inclined anterodorsally, forming angle of c. 20° with body axis. Anterior tip of upper jaw slightly before vertical through lower-jaw tip. Posterior margins of preopercle and opercle indistinct, covered with skin and generally rounded with slightly elongated flap on upper part, respectively. Gill opening wide, its uppermost point slightly below horizontal through dorsal margin of orbit in lateral view.
Lateral line system. Cephalic sensory pores moderately developed, covering most of head except for lower part of cheek and area adjacent to dorsal-fin origin. Mandibular pore positions 1 and 2 each with a single similarly-sized pore; position 3 with a single pore (largest size of mandibular pores); positions 4 and 5 with 1 (only left side of KAUM–I. 174227) or 2 and 6 or 7 pores, respectively. Lateral-line pores moderate, mostly in single series above and below embedded lateral-line tubes. Lateral line ending below 4th (KAUM–I. 174226) or 6th (KAUM–I. 174226) soft rays of dorsal-fin rays.
Scales. Scales mostly missing, scaled area and scale counts estimated from scale pockets. Lateral surface of body and belly scaled, except above and slightly below lateral line, area anterior to vertical below 4th (KAUM–I. 174227) or 5th (KAUM–I. 174226) dorsal-fin spine, pectoral-fin base, and chest. Head region and bases of vertical fins completely naked.
Fins. Dorsal fin moderately low, its profile relatively uniform except for anterior part and slightly notched junction of spinous and segmented rays; 1st dorsal-fin spine distinctly short, its base located between uppermost point of gill opening and posteriormost tip of flap on opercle; all dorsal rays branched distally. Anal fin of similar height to dorsal fin, its origin vertically level with base of 1st (KAUM–I. 174226) or 2nd (KAUM–I. 174227, NSMT-P 130174) dorsal-fin soft ray; last anal-fin ray close to caudal-fin base and vertically level with last dorsal-fin ray; all fin rays branched distally. Pelvic-fin origin anterior to vertical through dorsal-fin origin; first ray of pelvic fin robust, not tightly bound to second ray; membrane between first and second rays incised distally; second ray longest, innermost 3 rays branched. Pectoral-fin base below 2nd and 3rd dorsal-fin spine bases. Caudal fin rounded posteriorly.
Osteological features. Nasal short, tube-like. Vomer rhombic, with two tiny conical teeth anteriorly. Lateral ethmoid somewhat broad, articulating with 1st infraorbital and palatine ventrally. Palatine robust anteriorly, tapering posteriorly, without teeth. Infraorbitals relatively slender, comprising 5 elements, including dermosphenotic; 1st infraorbital longest, 3rd with suborbital shelf, 5th (= dermosphenotic) firmly attached to sphenotic. Basisphenoid crescentic. Frontal tapering anteriorly, 6 large dorsal openings for sensory canal from anteriormost tip to lateral aspect. Left and right parietals separated by supraoccipital. Anterior and posterior tips of supraoccipital strongly pointed. Sphenotic not expanded. Supratemporals associated with parietal and pterotic.
Premaxilla with a single row of conical teeth, except for posterior end. Maxilla long, posteriorly broadly expanded with slightly rounded corners. Supramaxilla small, on upper posterior end of maxilla. Dentary with a single row of conical teeth; 5 large ventral openings (including on posterior tip) from mandibular sensory canal. Anguloarticular large, its anterior projection fitting into dentary notch; coronoid process strongly pointed, directed anterodorsally. Retroarticular small, on ventroposterior corner of anguloarticular. Hyomandibular broadly attached to sphenotic and pterotic. Ectopterygoid and symplectic slender. Entopterygoid forming a large shelf. Metapterygoid and quadrate present but poorly resolved, Opercle with 2 strong and 1 weak ridge. Preopercle with 5 large openings from preopercular sensory canal. Subopercle small, its anterior tip pointed. Interopercle triangular, size similar to subopercle. Six long recurved branchiostegal rays.
Posttemporal L-shaped, forked, dorsal limb articulating with epiotic, an opening on posterior corner. Supracleithrum rod-like. Cleithrum with a large dorsal blade, receiving supracleithrum. Dorsal postcleithrum rectangular, articulating with cleithrum and scapula. Ventral postcleithrum long, narrow. Scapula widely separated from coracoid. Pectoral-fin radials comprising 4 elements, lowermost distinctly largest. Supraneural bone absent. Anterior dorsal- and anal fin interdigitation patterns //1/1+1/1/ and //1+1/1/1/1/, respectively.
ColorationFresh coloration of holotype and KAUM–I. 174227. Head ground color reddish-brown dorsally, reddish-white ventrally. Iris generally reddish-brown, except for whitish area ventrally, with four faint dark red lines radiating from pupil. Two faint dark-red oblique lines, extending from just behind eye to middle of nape and upper part of cheek, respectively. Five or six whitish blotches on cheek and opercle. Floor of mouth entirely white No blotches or stripes on snout, suborbital region, and both jaws. Body reddish-brown, with 3 or 4 longitudinal rows of c. 8–10 whitish blotches of size distinctly smaller than blotches on head region; upper one or two rows and anterior part of lower two rows of blotches somewhat indistinct. Two whitish blotches on pectoral-fin base, lower blotch distinctly the larger. Dorsal- and anal-fin bases edged with dark reddish-brown, anterior edge of former extending slightly below lateral line (sometimes interrupted by body ground color). Spinous dorsal fin greenish- or yellowish-brown; an ocellus between 2nd to 5th spines, 4–6 white spots forming a longitudinal row just behind ocellus. Soft-rayed part of dorsal fin and anal fin hyaline or faint reddish-brown, with two and one reddish-orange stripes, respectively; upper stripe of former through distal edge, remaining stripes at c. 1/3 height of both fins. Pelvic-fin rays whitish and membrane hyaline with melanophores. Pectoral and caudal fins uniformly faint orange or reddish-yellow.
Fresh coloration of NSMT-P 130174. Generally similar to other type specimens, with the following differences. Head and body yellow. Whitish blotches on body more distinct. A whitish blotch on pectoral-fin base. Vertical fins faintly yellow (details of pigmentation patterns not visible), an ocellus on spinous dorsal fin. Pelvic fins white.
Color in alcohol. Head and body generally blackish-gray. Ventral part of head and belly white. Whitish blotches on cheek, opercle, and pectoral-fin base (in fresh condition) faded, traces of blotches on body represented by non-pigmented areas. Spinous dorsal fin generally blackish-gray, an ocellus apparent (with hyaline white edge), but longitudinal row of white spots faded. Soft-rayed part of dorsal and anal fins hyaline, reddish-orange stripes (in fresh condition) retained as blackish-gray stripes. Pelvic-fin rays white, membrane hyaline with melanophores. Pectoral and caudal fins uniformly translucent white.
Distribution and habitatCurrently known only from the Osumi and Ryukyu islands, southern Japan in depths of 35–57 m (Fig. 6). The Ryukyu specimen (NSMT-P 130174) was collected from a sandy gravel bottom.
Figure 6. Distributional records of Opistognathus ctenion.
EtymologyThe specific name is a noun in apposition derived from the Greek diminutive κτενίον, meaning “a small comb”. It refers to the low gill raker numbers in the new species, one of the lowest recorded for Indo-Pacific species of Opistognathus (see below).
ComparisonsOpistognathus ctenion keys out to couplet 25 in Smith-Vaniz’s (2023) key to species of Opistognathus (including all valid species known from the Indo-West Pacific to date). The new species is most similar to the allopatric Opistognathus triops Smith-Vaniz, 2023 in having the following characters: posterior end of upper jaw rigid, without flexible lamina; dorsal-fin rays XI, 16–18; anal-fin rays II, 17; vertebrae 10 + 22 = 32; longitudinal scale rows c. 40–50; body scales absent anterior to vertical below 4th or 5th dorsal-fin spine; vomerine teeth 2; lateral line terminating below 4th–6th soft ray of dorsal fin; and spinous dorsal fin with an ocellus between 2nd to 5th spines. However, O. ctenion differs distinctly from O. triops in having fewer gill rakers (6 or 7 + 13 or 14 = 20 or 21 in O. ctenion vs 8 or 9 + 16–18 = 24–27 in O. triops), usually 2 and 6 or 7 pores included in the 4th and 5th mandibular pore positions, respectively (vs 1 and 2–4 pores, respectively), two reddish-orange stripes on the soft-rayed part of the dorsal fin (vs three broken brown stripes), a uniformly faint orange or reddish-yellow caudal fin (vs hyaline with three brown bars), and no blotches or stripes on the snout, suborbital region, and both jaws (vs 4 or 5 brown lines radiating from orbit). In addition, O. ctenion apparently occupies a slightly deeper water habitat than O. triops (currently known from 35–57 m depth vs 12–32 m depth).
The total of 20 or 21 gill rakers in O. ctenion is one of the lowest among the Indo-Pacific species of Opistognathus, with only two species sharing similar counts [viz., Opistognathus albomaculatus Smith-Vaniz, 2023 with 19–22 gill rakers; and Opistognathus reticulatus (McKay, 1969) with 21–23; see Smith-Vaniz (2023: table 12)]. Although O. ctenion is unlikely to be misidentified as O. reticulatus due to significant differences in body color, it is somewhat similar to O. albomaculatus in sharing whitish blotches on the body. However, the former can be easily distinguished from O. albomaculatus by the ocellus on the spinous dorsal fin (vs a striped pattern in O. albomaculatus). Dorsal- and anal-fin ray, and caudal vertebral numbers, as well as vomerine teeth condition, are also useful for distinguishing between the two species (viz., XI, 16–18 and II, 17, respectively in O. ctenion vs X, 19–21 and II, 18–20 in O. albomaculatus; 22 vs 23–25; and two teeth present vs teeth absent).
AcknowledgmentsWe are especially grateful to K. Kubota (Kagoshima University), S. Ohtsuka and Y. Kondo (Hiroshima University), Captain K. Nakaguchi and the crew of the R/V Toyoshio-maru for their assistance in collecting the specimens of the new species; S. Nomura, T. Kutsuna and Y. Shigeta (NSMT) for their efforts on proper maintenance of micro-CT scanner and software in Research Wing, Tsukuba District; G. S. Hardy (Ngunguru, New Zealand) for reading the manuscript and providing help with English; W. Smith-Vaniz (Florida Museum of Natural History) for reading the manuscript and providing valuable comments.
Additional informationConflict of interestThe authors have declared that no competing interests exist.
Ethical statementNo ethical statement was reported.
FundingThis study was supported in part by a Grant-in-Aid from the Japan Society for the Promotion of Science for JSPS Fellows to KF (PD: 22J01404); JSPS KAKENHI Grant Numbers 20H03311 and 21H03651, the JSPS Core-to-Core CREPSUM JPJSCCB20200009, and the “Establishment of Glocal Research and Education Network in the Amami Islands” project of Kagoshima University adopted by the Ministry of Education, Culture, Sports, Science and Technology, Japan to HM; and the Integrated Research Program “Geological, Biological, and Anthropological Histories in Relation to the Kuroshio Current” of the National Museum of Nature and Science, Tsukuba (2016–2021) and JSPS KAKENHI Grant Number JP21K01009 to GS.
Author contributionsK.F. was responsible for the study design, generation and analysis of the data, and wrote the original draft manuscript. H.M. and G.S. were responsible for field work, generation and analysis of data, and review and editing of the manuscript. All authors read the manuscript and approved the final version.
Author ORCIDsKyoji Fujiwara https://orcid.org/0000-0001-7577-8333
Hiroyuki Motomura https://orcid.org/0000-0002-7448-2482
Gento Shinohara https://orcid.org/0000-0002-8071-9239
Data availabilityAll of the data that support the findings of this study are available in the main text.
References
Kyoji Fujiwara, Hiroyuki Motomura, Gento ShinoharaAbstractOpistognathus ctenion sp. nov. (Perciformes: Opistognathidae) is described on the basis of three specimens (17.3–30.6 mm in standard length) collected from the Osumi and Ryukyu islands, southern Japan in depths of 35–57 m. Although most similar to Opistognathus triops, recently described from Tonga and Vanuatu, the new species differs in mandibular pore arrangement, dorsal- and caudal-fin coloration, fewer gill rakers, and lacks blotches or stripes on the snout, suborbital region and both jaws.
Key wordsActinopterygii, dredge, new species, Osumi Islands, Ryukyu Islands, taxonomy
IntroductionOpistognathus Cuvier, 1816 is the most speciose genus of jawfishes (Perciformes: Opistognathidae), being distributed worldwide in tropical and temperate regions, except for the eastern Atlantic Ocean and Mediterranean Sea (Smith-Vaniz 2023); most species of Opistognathus occur in the Indo-West Pacific. A recent review of the genus by Smith-Vaniz (2023) recognized 60 valid species, 18 being new, and additional new species of Opistognathus were predicted. To date, valid species of Opistognathus total 91 overall (Smith-Vaniz 2023).
Examination of specimens in the Kagoshima University Museum, Japan (KAUM) and the National Museum of Nature and Science, Japan (NSMT) revealed an unidentified species of Opistognathus, collected in 35–57 m depth off the Osumi and Ryukyu islands, southern Japan. In common with the majority of species of Opistognathus, the number of known examples of the present species is small, due to difficulties in collecting, attributed to their small body size and cryptic habitat [for details see Smith-Vaniz (2023)]. Notwithstanding, the species is clearly distinct, having a unique combination of meristic characters and fresh coloration, and is here formally described as a new to science.
Material and methodsMorphological observationCounts and measurements followed Smith-Vaniz (2023). Standard length (SL) was measured to the nearest 0.1 mm. Other measurements were made to the nearest 0.01 mm using needle-point calipers under a dissecting microscope (ZEISS Stemi DV4). Counts of vertebrae and fin rays, plus dorsal- and anal-fin pterygiophores, were examined from radiographs. Further osteological characters were investigated by computed tomography (CT) scanning using inspeXio SMX-225CR FPD HR Plus (Shimadzu, Kyoto) at 100 kV and 120 μA at a resolution of 18 μm, and three-dimensional reconstruction images produced by the rendering software VGSTUDIO MAX ver. 3.3 (Volume Graphics, Nagoya).
Preparation of figuresPhotographs of preserved specimens were taken with a Nikon D850 camera using an internal focus bracketing function; sets of multifocal images were then collated into a composite image, using Adobe Photoshop. The distribution map was prepared using GMT ver. 5.3.1, with data from GSHHG (Wessel and Smith 1996). The names and grouping of islands in southern Japan (belonging to Kagoshima and Okinawa prefectures) follow Motomura and Matsunuma (2022: fig. 5.2).
Comparative dataMorphological characters of comparative species of Opistognathus are cited from Smith-Vaniz (2023).
Results and discussion Opistognathus ctenion sp. nov.https://zoobank.org/66D79DFB-6CAA-4E18-A766-B2F117333C13
Figs 1, 2, 3, 4, 5, 6; Table 1 New English name: Japanese Whitespotted Jawfish New standard Japanese name: Shiratama-agoamadaiType materialHolotype. KAUM–I. 174226, 30.6 mm SL, off Mage-shima Island, Osumi Islands, Kagoshima, Japan, 35 m depth, dredge, 29 Sept. 2022, K. Kubota. Paratypes. KAUM–I. 174227, 26.2 mm SL, collected with holotype; NSMT-P 130174, 17.3 mm SL, southwest of Nagannu Island, Kerama Islands, southern Ryukyu Islands, Okinawa, Japan (26°14′33"N, 127°31′19"E–26°14′30"N, 127°31′24"E), 53–57 m depth, dredge operated by R/V Toyoshio-maru (Hiroshima University), 19 May 2017, G. Shinohara.
DiagnosisA species of Opistognathus distinguished from congeners by the following combination of characters: posterior end of upper jaw rigid, without flexible lamina; dorsal-fin rays XI, 16–18; anterior dorsal-fin spines very stout and straight, and their distal ends not transversely forked; anal-fin rays II, 17; gill rakers 6 or 7 + 13 or 14 = 20 or 21; vertebrae 10 + 22 = 32; longitudinal scale rows c. 40–50; lateral line terminating below 4th–6th soft ray of dorsal fin; 4th and 5th mandibular pore positions usually included 2 and 6–7 pores, respectively; body scales absent anterior to vertical below 4th or 5th dorsal-fin spine; vomerine teeth 2; body reddish-brown with 3 or 4 longitudinal rows of c. 8–10 whitish blotches; cheek and opercle with five or six whitish blotches; snout, suborbital region, and both jaws without blotches or stripes; spinous dorsal fin with ocellus between 2nd to 5th spines; dorsal-fin soft-rayed portion with two reddish-orange stripes; pectoral-fin base with one or two whitish blotches; caudal fin uniformly faint orange or reddish-yellow.
DescriptionGeneral appearance of type specimens as in Figs 1, 2 and 3. Lateral line system and osteological features of the holotype are given in Figs 4 and 5, respectively. Lateral line system and scale descriptions based on KAUM–I. 174226, 174227 (not available for NSMT-P 130174 due to poor specimen condition). Counts and measurements of type specimens are given in Table 1.
Table 1.
Download as
CSV
XLSXCounts and measurements of Opistognathus ctenion.
HolotypeParatypeParatype
KAUM–I. 174226KAUM–I. 174227NSMT-P 130174
Standard length (mm; SL)30.626.217.3
Counts
Dorsal-fin raysXI, 16XI, 18XI, 18
Anal-fin raysII, 17II, 17II, 17
Total pectoral-fin rays19 (left) / 19 (right)19 / 1919 / –
Pelvic-fin raysI, 5I, 5I, 5
Procurrent caudal-fin rays5 + 55 + 5–
Branched caudal-fin rays12––
Segmented caudal-fin rays8 + 8 = 168 + 8 = 168 + 8 = 16
Longitudinal scale rowsc. 40–50c. 40–50–
Vertebrae10 + 22 = 3210 + 22 = 3210 + 22 = 32
Gill rakers7 + 13 / 7 + 14 = 20 / 216 + 14 / 6 + 14 = 20 / 20– / 7 + 14 = 21
Measurements (% SL)
Pre-dorsal-fin length32.332.535.1
Pre-anal-fin length63.359.765.1
Dorsal-fin base length62.963.559.8
Anal-fin base length34.337.034.2
Pelvic-fin length22.621.121.7
Caudal-fin length20.923.222.2
Body depth15.316.010.3
Caudal-peduncle depth7.98.06.5
Head length32.331.934.3
Postorbital length19.820.519.1
Upper-jaw length17.417.217.4
Postorbital-jaw length6.85.54.3
Orbit diameter10.010.511.2
As % of head length
Postorbital length61.364.255.6
Upper-jaw length53.953.850.8
Postorbital-jaw length21.217.312.5
Orbit diameter30.932.832.7– indicates no data due to poor condition.
Figure 1. Holotype of Opistognathus ctenion (KAUM–I. 174226, 30.6 mm SL, off Mage-shima island, Osumi Islands, Kagoshima, Japan) A fresh and B preserved specimens photographed by KAUM and K. Fujiwara, respectively C X-ray image, photographed by K. Fujiwara.
Figure 2. Fresh coloration of two paratypes (A, C KAUM–I. 174226, 30.6 mm SL B, D KAUM–I. 174227, 26.2 mm SL) of Opistognathus ctenion, photographed by KAUM A, B lateral views C, D dorsal views.
Figure 3. Small paratype of Opistognathus ctenion (NSMT-P 130174, 17.3 mm SL) A fresh and B preserved specimens, photographed by G. Shinohara and K. Fujiwara, respectively.
Figure 4. Head of holotype of Opistognathus ctenion (KAUM–I. 174226, 30.6 mm SL), showing cephalic sensory pores (left column cyanine blue stain; right column solid yellow). Photographed by K. Fujiwara.
Figure 5. Three-dimensional reconstruction of head and anterior body in Opistognathus ctenion (KAUM–I. 174226, 30.6 mm SL), based on CT scanning. Photographed by G. Shinohara and K. Fujiwara. Abbreviations: ACh, anterior ceratohyal; Ana, anguloarticular; Bh, basihyal; Br, branchiostegal rays; Bsph, basisphenoid; Cl, cleithrum; Cor, coracoid; De, dentary; DHh, dorsal hypohyal; DPcl, dorsal postcleithrum; Ect, ectopterygoid; Ent, entopterygoid; Epoc, epiotic; Exoc, exoccipital; Fr, frontal; Hy, hyomandibular; Ih, interhyal, IO1 to IO5, 1st to 5th infraorbitals, respectively; Iop, interopercle; LE, lateral ethmoid; Met, metapterygoid; Mx, maxilla; Na, nasal; Op, opercle; Pa, parietal; Pal, palatine; PecR, pectoral radial; Pmx, premaxilla; Pop, preopercle; Psph, parasphenoid; Pt, posttemporal; Pte, pterotic; Q, quadrate; Ra, retroarticular; Sc, scapula; Scl, supracleithrum; Smx, supramaxilla; Soc, supraoccipital; Sop, subopercle; Sph, sphenotic; Ste, supratemporal; Sym, symplectic; Ur, urohyal; V1, 1st vertebral centrum; Vo, vomer; and VPcl, ventral postcleithrum. Asterisks indicate poorly resolved features.
Head and body. Body elongate, compressed anteriorly, progressively more compressed posteriorly. Anus situated just before anal-fin origin. Head cylindrical, its profile rounded. Eyes somewhat large, located dorsolaterally. Anterior nostril a short membranous tube with a tiny tentacle on posterior rim, when depressed not reaching posterior nostril; situated about mid-way between posterior nostril and dorsal margin of upper lip. Posterior nostril opening elliptical. Mouth terminal, obliquely inclined anterodorsally, forming angle of c. 20° with body axis. Anterior tip of upper jaw slightly before vertical through lower-jaw tip. Posterior margins of preopercle and opercle indistinct, covered with skin and generally rounded with slightly elongated flap on upper part, respectively. Gill opening wide, its uppermost point slightly below horizontal through dorsal margin of orbit in lateral view.
Lateral line system. Cephalic sensory pores moderately developed, covering most of head except for lower part of cheek and area adjacent to dorsal-fin origin. Mandibular pore positions 1 and 2 each with a single similarly-sized pore; position 3 with a single pore (largest size of mandibular pores); positions 4 and 5 with 1 (only left side of KAUM–I. 174227) or 2 and 6 or 7 pores, respectively. Lateral-line pores moderate, mostly in single series above and below embedded lateral-line tubes. Lateral line ending below 4th (KAUM–I. 174226) or 6th (KAUM–I. 174226) soft rays of dorsal-fin rays.
Scales. Scales mostly missing, scaled area and scale counts estimated from scale pockets. Lateral surface of body and belly scaled, except above and slightly below lateral line, area anterior to vertical below 4th (KAUM–I. 174227) or 5th (KAUM–I. 174226) dorsal-fin spine, pectoral-fin base, and chest. Head region and bases of vertical fins completely naked.
Fins. Dorsal fin moderately low, its profile relatively uniform except for anterior part and slightly notched junction of spinous and segmented rays; 1st dorsal-fin spine distinctly short, its base located between uppermost point of gill opening and posteriormost tip of flap on opercle; all dorsal rays branched distally. Anal fin of similar height to dorsal fin, its origin vertically level with base of 1st (KAUM–I. 174226) or 2nd (KAUM–I. 174227, NSMT-P 130174) dorsal-fin soft ray; last anal-fin ray close to caudal-fin base and vertically level with last dorsal-fin ray; all fin rays branched distally. Pelvic-fin origin anterior to vertical through dorsal-fin origin; first ray of pelvic fin robust, not tightly bound to second ray; membrane between first and second rays incised distally; second ray longest, innermost 3 rays branched. Pectoral-fin base below 2nd and 3rd dorsal-fin spine bases. Caudal fin rounded posteriorly.
Osteological features. Nasal short, tube-like. Vomer rhombic, with two tiny conical teeth anteriorly. Lateral ethmoid somewhat broad, articulating with 1st infraorbital and palatine ventrally. Palatine robust anteriorly, tapering posteriorly, without teeth. Infraorbitals relatively slender, comprising 5 elements, including dermosphenotic; 1st infraorbital longest, 3rd with suborbital shelf, 5th (= dermosphenotic) firmly attached to sphenotic. Basisphenoid crescentic. Frontal tapering anteriorly, 6 large dorsal openings for sensory canal from anteriormost tip to lateral aspect. Left and right parietals separated by supraoccipital. Anterior and posterior tips of supraoccipital strongly pointed. Sphenotic not expanded. Supratemporals associated with parietal and pterotic.
Premaxilla with a single row of conical teeth, except for posterior end. Maxilla long, posteriorly broadly expanded with slightly rounded corners. Supramaxilla small, on upper posterior end of maxilla. Dentary with a single row of conical teeth; 5 large ventral openings (including on posterior tip) from mandibular sensory canal. Anguloarticular large, its anterior projection fitting into dentary notch; coronoid process strongly pointed, directed anterodorsally. Retroarticular small, on ventroposterior corner of anguloarticular. Hyomandibular broadly attached to sphenotic and pterotic. Ectopterygoid and symplectic slender. Entopterygoid forming a large shelf. Metapterygoid and quadrate present but poorly resolved, Opercle with 2 strong and 1 weak ridge. Preopercle with 5 large openings from preopercular sensory canal. Subopercle small, its anterior tip pointed. Interopercle triangular, size similar to subopercle. Six long recurved branchiostegal rays.
Posttemporal L-shaped, forked, dorsal limb articulating with epiotic, an opening on posterior corner. Supracleithrum rod-like. Cleithrum with a large dorsal blade, receiving supracleithrum. Dorsal postcleithrum rectangular, articulating with cleithrum and scapula. Ventral postcleithrum long, narrow. Scapula widely separated from coracoid. Pectoral-fin radials comprising 4 elements, lowermost distinctly largest. Supraneural bone absent. Anterior dorsal- and anal fin interdigitation patterns //1/1+1/1/ and //1+1/1/1/1/, respectively.
ColorationFresh coloration of holotype and KAUM–I. 174227. Head ground color reddish-brown dorsally, reddish-white ventrally. Iris generally reddish-brown, except for whitish area ventrally, with four faint dark red lines radiating from pupil. Two faint dark-red oblique lines, extending from just behind eye to middle of nape and upper part of cheek, respectively. Five or six whitish blotches on cheek and opercle. Floor of mouth entirely white No blotches or stripes on snout, suborbital region, and both jaws. Body reddish-brown, with 3 or 4 longitudinal rows of c. 8–10 whitish blotches of size distinctly smaller than blotches on head region; upper one or two rows and anterior part of lower two rows of blotches somewhat indistinct. Two whitish blotches on pectoral-fin base, lower blotch distinctly the larger. Dorsal- and anal-fin bases edged with dark reddish-brown, anterior edge of former extending slightly below lateral line (sometimes interrupted by body ground color). Spinous dorsal fin greenish- or yellowish-brown; an ocellus between 2nd to 5th spines, 4–6 white spots forming a longitudinal row just behind ocellus. Soft-rayed part of dorsal fin and anal fin hyaline or faint reddish-brown, with two and one reddish-orange stripes, respectively; upper stripe of former through distal edge, remaining stripes at c. 1/3 height of both fins. Pelvic-fin rays whitish and membrane hyaline with melanophores. Pectoral and caudal fins uniformly faint orange or reddish-yellow.
Fresh coloration of NSMT-P 130174. Generally similar to other type specimens, with the following differences. Head and body yellow. Whitish blotches on body more distinct. A whitish blotch on pectoral-fin base. Vertical fins faintly yellow (details of pigmentation patterns not visible), an ocellus on spinous dorsal fin. Pelvic fins white.
Color in alcohol. Head and body generally blackish-gray. Ventral part of head and belly white. Whitish blotches on cheek, opercle, and pectoral-fin base (in fresh condition) faded, traces of blotches on body represented by non-pigmented areas. Spinous dorsal fin generally blackish-gray, an ocellus apparent (with hyaline white edge), but longitudinal row of white spots faded. Soft-rayed part of dorsal and anal fins hyaline, reddish-orange stripes (in fresh condition) retained as blackish-gray stripes. Pelvic-fin rays white, membrane hyaline with melanophores. Pectoral and caudal fins uniformly translucent white.
Distribution and habitatCurrently known only from the Osumi and Ryukyu islands, southern Japan in depths of 35–57 m (Fig. 6). The Ryukyu specimen (NSMT-P 130174) was collected from a sandy gravel bottom.
Figure 6. Distributional records of Opistognathus ctenion.
EtymologyThe specific name is a noun in apposition derived from the Greek diminutive κτενίον, meaning “a small comb”. It refers to the low gill raker numbers in the new species, one of the lowest recorded for Indo-Pacific species of Opistognathus (see below).
ComparisonsOpistognathus ctenion keys out to couplet 25 in Smith-Vaniz’s (2023) key to species of Opistognathus (including all valid species known from the Indo-West Pacific to date). The new species is most similar to the allopatric Opistognathus triops Smith-Vaniz, 2023 in having the following characters: posterior end of upper jaw rigid, without flexible lamina; dorsal-fin rays XI, 16–18; anal-fin rays II, 17; vertebrae 10 + 22 = 32; longitudinal scale rows c. 40–50; body scales absent anterior to vertical below 4th or 5th dorsal-fin spine; vomerine teeth 2; lateral line terminating below 4th–6th soft ray of dorsal fin; and spinous dorsal fin with an ocellus between 2nd to 5th spines. However, O. ctenion differs distinctly from O. triops in having fewer gill rakers (6 or 7 + 13 or 14 = 20 or 21 in O. ctenion vs 8 or 9 + 16–18 = 24–27 in O. triops), usually 2 and 6 or 7 pores included in the 4th and 5th mandibular pore positions, respectively (vs 1 and 2–4 pores, respectively), two reddish-orange stripes on the soft-rayed part of the dorsal fin (vs three broken brown stripes), a uniformly faint orange or reddish-yellow caudal fin (vs hyaline with three brown bars), and no blotches or stripes on the snout, suborbital region, and both jaws (vs 4 or 5 brown lines radiating from orbit). In addition, O. ctenion apparently occupies a slightly deeper water habitat than O. triops (currently known from 35–57 m depth vs 12–32 m depth).
The total of 20 or 21 gill rakers in O. ctenion is one of the lowest among the Indo-Pacific species of Opistognathus, with only two species sharing similar counts [viz., Opistognathus albomaculatus Smith-Vaniz, 2023 with 19–22 gill rakers; and Opistognathus reticulatus (McKay, 1969) with 21–23; see Smith-Vaniz (2023: table 12)]. Although O. ctenion is unlikely to be misidentified as O. reticulatus due to significant differences in body color, it is somewhat similar to O. albomaculatus in sharing whitish blotches on the body. However, the former can be easily distinguished from O. albomaculatus by the ocellus on the spinous dorsal fin (vs a striped pattern in O. albomaculatus). Dorsal- and anal-fin ray, and caudal vertebral numbers, as well as vomerine teeth condition, are also useful for distinguishing between the two species (viz., XI, 16–18 and II, 17, respectively in O. ctenion vs X, 19–21 and II, 18–20 in O. albomaculatus; 22 vs 23–25; and two teeth present vs teeth absent).
AcknowledgmentsWe are especially grateful to K. Kubota (Kagoshima University), S. Ohtsuka and Y. Kondo (Hiroshima University), Captain K. Nakaguchi and the crew of the R/V Toyoshio-maru for their assistance in collecting the specimens of the new species; S. Nomura, T. Kutsuna and Y. Shigeta (NSMT) for their efforts on proper maintenance of micro-CT scanner and software in Research Wing, Tsukuba District; G. S. Hardy (Ngunguru, New Zealand) for reading the manuscript and providing help with English; W. Smith-Vaniz (Florida Museum of Natural History) for reading the manuscript and providing valuable comments.
Additional informationConflict of interestThe authors have declared that no competing interests exist.
Ethical statementNo ethical statement was reported.
FundingThis study was supported in part by a Grant-in-Aid from the Japan Society for the Promotion of Science for JSPS Fellows to KF (PD: 22J01404); JSPS KAKENHI Grant Numbers 20H03311 and 21H03651, the JSPS Core-to-Core CREPSUM JPJSCCB20200009, and the “Establishment of Glocal Research and Education Network in the Amami Islands” project of Kagoshima University adopted by the Ministry of Education, Culture, Sports, Science and Technology, Japan to HM; and the Integrated Research Program “Geological, Biological, and Anthropological Histories in Relation to the Kuroshio Current” of the National Museum of Nature and Science, Tsukuba (2016–2021) and JSPS KAKENHI Grant Number JP21K01009 to GS.
Author contributionsK.F. was responsible for the study design, generation and analysis of the data, and wrote the original draft manuscript. H.M. and G.S. were responsible for field work, generation and analysis of data, and review and editing of the manuscript. All authors read the manuscript and approved the final version.
Author ORCIDsKyoji Fujiwara https://orcid.org/0000-0001-7577-8333
Hiroyuki Motomura https://orcid.org/0000-0002-7448-2482
Gento Shinohara https://orcid.org/0000-0002-8071-9239
Data availabilityAll of the data that support the findings of this study are available in the main text.
References
- Cuvier G (1816) Le Règne Animal distribué d’après son organisation pour servir de base à l’histoire naturelle des animaux et d’introduction à l’anatomie comparée. Les reptiles, Les poissons, Les mollusques et Les annélides. 1st edn. Vol. 2. Chez Deterville, Paris, [xviii +] 532 pp. https://www.biodiversitylibrary.org/page/1848835#page/7/mode/1up
- McKay RJ (1969) The genus Tandya in Western Australia, with a description of a new opisthognathid fish, Tandya reticulata sp. nov. Journal of the Royal Society of Western Australia 52: 1–2. https://www.biodiversitylibrary.org/item/173687#page/1/mode/1up
- Motomura H, Matsunuma M (2022) Fish diversity along the Kuroshio Current. In: Kai Y, Motomura H, Matsuura K (Eds) Fish diversity of Japan. Evolution, Zoogeography, and Conservation. Springer Nature Singapore Pte Ltd., Singapore, 63–78. https://doi.org/10.1007/978-981-16-7427-3_5
- Smith-Vaniz WF (2023) Review of Indo-West Pacific jawfishes (Opistognathus: Opistognathidae), with descriptions of 18 new species. Zootaxa 5252(1): 1–180. https://doi.org/10.11646/zootaxa.5252.1.1
- Wessel P, Smith WHF (1996) A global self-consistent, hierarchical, high-resolution shoreline database. Journal of Geophysical Research 101(B4): 8741–8743. https://doi.org/10.1029/96JB00104
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Varicus roatanensis
Varicus prometheus
Two new species of Varicus from Caribbean deep reefs, with comments on the related genus Pinnichthys (Teleostei, Gobiidae, Gobiosomatini, Nes subgroup)
Katlyn M. Fuentes, Carole C. Baldwin, D. Ross Robertson, Claudia C. Lardizábal, Luke TornabeneAbstractTropical deep reefs (~40–300 m) are diverse ecosystems that serve as habitats for diverse communities of reef-associated fishes. Deep-reef fish communities are taxonomically and ecologically distinct from those on shallow reefs, but like those on shallow reefs, they are home to a species-rich assemblage of small, cryptobenthic reef fishes, including many species from the family Gobiidae (gobies). Here we describe two new species of deep-reef gobies, Varicus prometheus sp. nov. and V. roatanensis sp. nov., that were collected using the submersible Idabel from rariphotic reefs off the island of Roatan (Honduras) in the Caribbean. The new species are the 11th and 12th species of the genus Varicus, and their placement in the genus is supported by morphological data and molecular phylogenetic analyses. Additionally, we also collected new specimens of the closely-related genus and species Pinnichthys aimoriensis during submersible collections off the islands of Bonaire and St. Eustatius (Netherland Antilles) and included them in this study to expand the current description of that species and document its range extension from Brazil into the Caribbean. Collectively, the two new species of Varicus and new records of P. aimoriensis add to our growing knowledge of cryptobenthic fish diversity on deep reefs of the Caribbean.
full paper at:- zookeys.pensoft.net/article/107551/
==========================
Two new species of Varicus from Caribbean deep reefs, with comments on the related genus Pinnichthys (Teleostei, Gobiidae, Gobiosomatini, Nes subgroup)
Katlyn M. Fuentes, Carole C. Baldwin, D. Ross Robertson, Claudia C. Lardizábal, Luke TornabeneAbstractTropical deep reefs (~40–300 m) are diverse ecosystems that serve as habitats for diverse communities of reef-associated fishes. Deep-reef fish communities are taxonomically and ecologically distinct from those on shallow reefs, but like those on shallow reefs, they are home to a species-rich assemblage of small, cryptobenthic reef fishes, including many species from the family Gobiidae (gobies). Here we describe two new species of deep-reef gobies, Varicus prometheus sp. nov. and V. roatanensis sp. nov., that were collected using the submersible Idabel from rariphotic reefs off the island of Roatan (Honduras) in the Caribbean. The new species are the 11th and 12th species of the genus Varicus, and their placement in the genus is supported by morphological data and molecular phylogenetic analyses. Additionally, we also collected new specimens of the closely-related genus and species Pinnichthys aimoriensis during submersible collections off the islands of Bonaire and St. Eustatius (Netherland Antilles) and included them in this study to expand the current description of that species and document its range extension from Brazil into the Caribbean. Collectively, the two new species of Varicus and new records of P. aimoriensis add to our growing knowledge of cryptobenthic fish diversity on deep reefs of the Caribbean.
full paper at:- zookeys.pensoft.net/article/107551/
==========================
A new species of rheophilic armored catfish of Rineloricaria (Siluriformes: Loricariidae) from the Vaupés River, Amazonas basin, Colombia
Alexander Urbano-Bonilla, Alejandro Londoño-Burbano, Tiago P. Carvalho
First published: 10 July 2023
https://doi.org/10.1111/jfb.15500
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SHAREAbstractA new rheophilic species of the genus Rineloricaria is described for the Amazon basin in Colombia. Rineloricaria cachivera n. sp. differs from its congeners by having anterior to the first predorsal plate, an inconspicuous saddle-like mark; the presence of dark, diffuse blotches, present as unified dark colouration along most of the dorsal portion of the head, without bands or spots on the head; a long snout that occupies more than half the head length (HL), between 58.0% and 66.3% HL; a naked portion on the cleithral area from the border of lower lip reaching the origin of pectoral fin; and by having five series of lateral plates in longitudinal rows below the dorsal fin. The new species is morphologically similar to Rineloricaria daraha; however, it can be distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long finger papillae). An identification key to the Rineloricaria species of the Amazon River basin in Colombia is provided. The new species is herein categorized as Least Concern, following the IUCN criteria.
1 INTRODUCTIONThe armored catfish Rineloricaria Bleeker, 1862, has 71 valid species, being the richest genus in the family Loricariidae (Fricke et al., 2023). The genus is diagnosed by a combination of characteristics such as the presence of postorbital notch; lower lip with short round papillae; premaxilla with 7 to 15 teeth on each ramus; dentary teeth strong, deeply bicuspidate, and larger than premaxillary; colouration of the dorsal region with dark-brown bars or blotches; abdomen with a conspicuous polygonal pre-anal plate, usually bordered by three other large trapezoidal plates (Fichberg & Chamon, 2008) and some features of sexual dimorphism, which are traits not always present in the individuals available for examination (Londoño-Burbano & Urbano-Bonilla, 2018). Progress has been made in the taxonomic and phylogenetic relationships between Rineloricaria species (Covain & Fisch-Muller, 2007), and it is now demonstrated to be a monophyletic group based on molecular data (Costa-Silva et al., 2015; Covain et al., 2016) with wide interspecies morphological variation (e.g., body color and shape, arrangement of abdominal plates, shape of head, and distribution of hypertrophied odontodes; Vera-Alcaraz et al., 2012).
The wide distribution of Rineloricaria in the main Neotropical basins and environments reflects the diversity and morphological adaptations of its species (van der Sleen & Albert, 2017; Vera-Alcaraz et al., 2012). Some species occur in small drainages of slow to moderate-flowing waters, associated with sand, vegetation, and organic matter; others are rheophilic inhabiting fast-flowing rivers associated with rocks (Costa-Silva et al., 2021; Lima et al., 2005; Londoño-Burbano & Urbano-Bonilla, 2018; Rapp Py-Daniel & Fichberg, 2008; Rodriguez & Reis, 2008). Rheophilic environments have driven the evolution of armored catfish lineages in the family Loricariidae (Lujan & Conway, 2015); the rheophilic species of Rineloricaria exhibit consistent ecomorphological patterns and that is evidenced in the shape of the body, mouth, and buccal papillae (Bressman et al., 2020).
In Colombia, 11 species are present in different hydrographic basins: Pacific and Caribbean: Rineloricaria jubata (Boulenger 1902); Pacific: Rineloricaria sneiderni (Fowler 1944); Caribbean Rineloricaria rupestris (Schultz 1944) and Magdalena-Cauca and Caribbean: Rineloricaria magdalenae (Steindachner 1879); Orinoco: Rineloricaria eigenmanni (Pellegrin 1908) and Rineloricaria formosa Isbrücker & Nijssen 1979; Amazonas: Rineloricaria castroi Isbrücker & Nijssen 1984, Rineloricaria daraha Rapp Py-Daniel & Fichberg, 2008, Rineloricaria phoxocephala (Eigenmann & Eigenmann 1889), Rineloricaria lanceolata (Günther 1868) and Rineloricaria jurupari Londoño-Burbano & Urbano-Bonilla, 2018 (DoNascimiento et al., 2021). The diversity of species in Colombia may have been underestimated due to a lack of data and sampling, especially in the Amazon basin (Jézéquel, Tedesco, Bigorne, et al., 2020a). Of the main rivers that drain to the Amazon (e.g., in Colombia: Caquetá, Putumayo, Apaporis, and Vaupés), the Vaupés is located in a Miocene Andean tectonic upheaval known as the Vaupés Arch (10 Ma), which acts as a semi-permeable barrier for the dispersal of fish (Winemiler & Willis, 2011) dividing the Amazon and Orinoco basins (Mora et al., 2010). Located on its border with Brazil, this river has numerous rocky rapids (locally known as “Cachiveras,” or “Raudales”) along its course that serve as a habitat and act as hydrogeographic barriers for fish. In the exploration of these environments, a new species of the genus Rineloricaria was identified, and it is described herein. Additionally, an updated identification key for species present at the Colombian Amazon is provided.
2 MATERIALS AND METHODSFish collection follows animal care guidelines provided by the American Society of Ichthyologists and Herpetologists (2013) -https://www.asih.org/resources. The biological material of MPUJ collected in this expedition in the río Vaupés went through a process of amnesty by the Instituto de Investigación Alexander von Humboldt under Colombian law “article 6 of law 1955 of 2019.” Fishes were captured using hand-nets or hand-captured by active snorkeling dives in polls or rapids of the Vaupés River. Specimens were photographed in life following the scientific documentation protocols of Photafish (Garcia-Melo et al., 2019). The holotype was also photographed in the laboratory following similar protocols. When the collected specimens were euthanized, doses of 0.3 mL/0.25 L of clove oil were added (Syzygium aromaticum; Lucena et al., 2013) before fixation. Fishes were fixed in 10% formaldehyde and later preserved in 70% ethanol for storage. Counts and measurements were made on the left side of specimens when possible, using digital calipers to the nearest 0.1 mm. Measurement, plate series count, and nomenclature followed Vera-Alcaraz et al. (2012). The terms “main cusp” and “lateral cusp” follow Muller and Weber (1992). Institutional acronyms follow Sabaj (2020). Characteristics used to diagnose the new species from species that are not included in the item “Additional specimens examined” were analysed and compared using original and subsequent descriptions of each species. In the description, counts are followed by their frequency in parentheses, and an asterisk (*) indicates the count of the holotype. Conservation Assessment Tool-GeoCAT was used to assess the geographic range of the taxon in two approaches: (i) extent of occurrence (EOO) and (ii) area of occupancy (AOO). Both metrics are part of the IUCN Red List categories and criteria (IUCN Subcommittee on Standards and Petitions, 2022). This study adjusted the grid to 1 km2, following the criteria of Bachman et al. (2011) for aquatic ecosystems.
3 RESULTS3.1 R. cachivera new speciesurn:lsid:zoobank.org:pub:7E3CCD7A-6118-4D3C-ADD1-F89A06ADF735.
urn:lsid:zoobank.org:act:FA5DEFCE-5666-46DD-9D3E-1F6E8E138668.
(Figures 1 and 2; and Table 1).
FIGURE 1
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Holotype of Rineloricaria cachivera n. sp., MPUJ 14451, 122.8 mm standard length (LS), río Vaupés upstream Cachivera Tapira-llerao, Comunidad de Matapí, Mitú, Vaupés, Colombia.
FIGURE 2
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Paratypes of Rineloricaria cachivera n. sp. (a) Unpreserved specimen, río Vaupés at Resguardo Trubón. (b-c) MPUJ 14481, 114.4 mm standard length (LS), río Vaupés at Laguna Arcoiris small rocky bottom isolated lagoon from the river, Comunidad de Matapí, Mitú, Vaupés, Colombia.
TABLE 1. Morphometric data of holotype (H) and paratypes of Rineloricaria cachivera n. sp. (n = 4 including the holotype).
HolotypeMinimumMaximumMeanS.D.Standard length122.877.2122.8107.2-
Percentage of standard length
Head length24.721.925.124.11.48
Predorsal length37.137.137.837.40.33
Postdorsal length62.262.265.463.91.30
Prepectoral length22.421.322.421.80.48
Postpectoral length82.180.284.382.31.66
Prepelvic length36.036.036.736.30.28
Postpelvic length65.565.466.765.80.61
Pre-anal length50.950.051.450.90.62
Postanal length50.347.250.349.21.41
Unbranched dorsal-fin ray19.417.020.919.41.67
Unbranched pectoral-fin ray17.717.820.619.01.18
Unbranched pelvic-fin ray18.318.319.318.90.42
Unbranched anal-fin ray17.717.720.619.41.26
Thoracic length16.715.818.016.70.92
Abdominal length17.016.217.817.10.71
Cleithral width19.619.620.619.90.47
Depth at dorsal-fin origin13.311.314.412.61.45
Width at anal-fin origin14.713.115.014.20.89
Caudal peduncle depth1.51.41.71.50.11
Caudal peduncle width2.72.73.23.00.24
Percentage of head length
Snout length58.058.066.360.43.96
Eye diameter10.210.213.011.21.22
Maximum orbital diameter14.513.218.315.22.19
Interorbital width25.023.329.025.42.47
Internarial width9.69.615.411.82.73
Head depth44.836.251.543.26.54
Head width76.473.593.581.58.82
Free maxillary barbel5.65.38.36.61.42
Ventrorostral length9.98.310.59.60.94
Lower lip length22.420.123.721.81.57
3.3 ParatypesMPUJ 14375, 114.5, mm LS. Colombia, Vaupés Department, Mitú municipality, Negro River drainage, río Vaupés at Resguardo Trubón, 1° 12′ 8.38″ N, 70° 2′ 20.67″ W, 176 m a.s.l., coll, J. A. Maldonado-Ocampo et al., February 22, 2019. MPUJ 14481, 114.4 mm LS, Colombia, Vaupés Department, Mitú municipality, Negro River drainage, río Vaupés, Laguna Arcoiris small rocky bottom isolated lagoon from the river, Comunidad de Matapí, 1° 4′ 48.30″ 14495, 77.2 mm LS Colombia, Vaupés Department, Mitú municipality, Negro River drainage, río Vaupés at Comunidad de Matapí, 1° 4′ 49.16″ N, 69° 21′ 50.44″ W, 119 m a.s.l., coll, J. A. Maldonado-Ocampo et al., March 2, 2019.
3.4 DiagnosisThe new species differs from all its congeners by the following combination of characters: presence of a transverse dorsal band that is not well defined and is curved, similar to that band observed on anterior border of snout, anterior to the first predorsal plate (vs. transversal band absent; when present, first dorsal transversal band well defined, straight, not curved); presence of dark, diffuse blotches, present as unified dark colouration along most of dorsal portion of head, without bands or spots on head (vs. absence of dark, diffuse blotches, present as unified dark colouration along most of dorsal portion of head, without bands or spots on head); a long snout that occupies more than half the HL, between 58.0% and 66.3% HL (vs. short snout, occupying half or less than half of HL, usually less than 56% HL; except in R. daraha, R. lanceolata, R. malabarbai Rodriguez & Reis, 2008, Rineloricaria microlepidogaster [Regan 1904], and Rineloricaria osvaldoi Fichberg & Chamon, 2008); and naked portion on the cleithral region from border of lower lip reaching origin of pectoral fin (vs. naked portion of cleithral region not reaching origin of pectoral fin, beyond pectoral-fin origin, or portion totally covered by plates). Rineloricaria cachivera n. sp. is further distinguished by having five series of lateral plates in longitudinal rows below the dorsal fin (vs. four series of lateral plates in longitudinal rows below the dorsal fin in R. aurata (Knaack 2002), Rineloricaria beni (Pearson 1924), Rineloricaria cadeae (Hensel 1868), R. castroi, Rineloricaria catamarcensis (Berg 1895), Rineloricaria cubatonis (Steindachner 1907), Rineloricaria felipponei (Fowler 1943), Rineloricaria henselli (Steindachner 1907), R. jurupari, R. lanceolata, Rineloricaria langei Ingenito, Ghazzi, Duboc & Abilhoa 2008, Rineloricaria lima (Kner 1853), Rineloricaria longicauda Reis 1983, Rineloricaria magdalenae, Rineloricaria microlepidota (Steindachner 1907), Rineloricaria misionera Rodriguez & Miquelarena, 2005, Rineloricaria nigricauda (Regan 1904), Rineloricaria pareiacantha Mirande & Koerber 2015, Rineloricaria parva (Boulenger 1895), Rineloricaria quadrensis Reis 1983, Rineloricaria sanga Ghazzi 2008, Rineloricaria setepovos Ghazzi 2008, Rineloricaria sneiderni, Rineloricaria stellata Ghazzi 2008, Rineloricaria thrissoceps (Fowler 1943), Rineloricaria uracantha (Kner 1863), and Rineloricaria wolfei Fowler 1940). The new species is morphologically similar to R. daraha, a congener distributed in the río Negro basin (Brazil and Colombia); however, it can be easily distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long papillae).
3.5 DescriptionMorphometric data in Table 1. Largest specimen reaching 122.8 mm LS. Snout straight in lateral view, slightly raised on its tip. Dorsal profile straight to slightly convex from orbits to nuchal plate, and straight from dorsal origin to base of caudal-fin origin. Ventral profile of head straight; convex from anterior abdominal plates to anal-fin base, straight from that point to caudal-fin origin. Body and head wide, widening strongly at about origin of first infraorbital. Posterior portion of body with a noticeable narrowing at about half length of caudal peduncle. Five plates in infraorbital series, with sensory pores exposed ventrally. Snout tip with large oval naked area, but not extending laterally surpassing sensorial pore of first infraorbital. Poorly developed odontodes on head and trunk. Dorsum of head smooth, not presenting ridges on head and predorsal plates. Posterior margin of parieto-supraoccipital triangular. Dorsal margin of orbit not raised; postorbital notch shallow, not well developed. Eye large, round to slightly oval horizontally. Lower lip large, almost reaching anterior limit of abdominal plates, with lower border covered by 10 to 12 fringes on margin of each lobe. Round papillae covering lower lip, increasing in size toward dentary ramii, a line of more developed papillae near line with maxillary barbel. Teeth bicuspid, long, main cusp greater and wider than lateral, dentary teeth larger than premaxillary teeth, main cusp about twice length of lateral cusp. Premaxilla with 6(3*) or 8(1) teeth; dentary with 5(1*), 6(1), 7(1), 8(1) teeth. Five lateral plate series. Median lateral plates 27(2), or 28(2*). Lateral line complete. Lateral abdominal plates 9(2), 10(1), or 11(1*). Central abdominal plates well developed, slightly smaller anteriorly, having about 4–5 rows irregularly distributed. Abdominal plates covering entire abdomen, without naked areas. Posterior abdominal plates surrounding a well-defined pre-anal area, with three plates surrounding anus, one anterior and two lateral. Anterior margin of anterior abdominal plates slightly rounded or concave on its central portion. Dorsal fin I,7(4), dorsal-fin spinelet present, locking mechanism not functional; tip of depressed unbranched ray reaching fourth or fifth plate posterior to dorsal-fin base; tip of depressed last branched ray reaching third or fourth plate; distal margin falcate with unbranched and first branched rays longer than remaining, dorsal-fin base occupying 4(4) plates; pectoral fin I,6(4); tip of depressed unbranched ray reaching and slightly surpassing dorsal-fin origin; distal margin truncate. Pelvic fin i,5 (4), depressed unbranched ray slightly surpassing anal-fin origin. Anal fin i,5(4), with tip of depressed unbranched ray reaching sixth plate posterior to its base, depressed last branched ray reaching third or fourth plate posterior to its base; anal-fin base with three plates; distal margin truncate. Caudal fin emarginate, i,10,i (3) and i,9,i(2*); dorsal principal ray extended as long filament, filament about 2−4 times length of lower unbranched one (Figure 2a).
3.6 ColourationOverall ground colouration yellowish, presenting dark-brown portions, especially on dorsal surface (Figure 1). Dorsal surface of body mostly yellowish contrasting with darker saddle-like pigmentation areas, ventral portion of body lighter. Dorsal body with five wide saddle-like dark marks; first one at base of dorsal fin, second starting just posterior to end of adnate last branched dorsal-fin ray and three marks between adnate end of anal fin and caudal peduncle. Lighter areas between dark saddles presenting dark scattered spots. Posterior region of parieto-supraoccipital darker with an inconspicuous saddle-like mark; ventral surface of head light yellowish with dark spots on cheek plates and snout area. Dark-brown irregular spots covering the lateral margin of abdomen, the remaining portion with yellow ground colouration (Figures 1 and 2). All fins with a dark band occupying almost their entire surfaces. Colouration in life similar as in preserved specimens except for brighter yellowish ground colouration (Figure 2).
3.7 Sexual dimorphismIn adult males, the first ray (unbranched) of pelvic fins has an extension equal in width to the rest of the ray; it is filament-shaped but very thick (Figure 2a; this individual was lost in the expedition accident and the photograph).
3.8 Distribution, habitat, and physicochemistry of waterRineloricaria cachivera n. sp. is known from four localities in the middle Vaupés River, downstream from the municipality of Mitú in Colombia (Figures 3 and 4a–d). With dark waters, little transparency (Secci disk values: x˙116 ± 11.31 S.D. and x˙122.50 ± 10.61 S.D.), and deep zones in the area of the rapids (up to 18.6 m). The mean values with standard deviation (mean ± S.D.) of the temperature (28.15 ± 0.21°C–29.65 ± 0.21°C), dissolved oxygen in the water (7.63 mg/L ± 0.25) and the surface (6.41 mg/L ± 0.01) are variable. In subaquatic dives with a diving mask, the specimens were collected by hand. In these rheophilic environments that are characterized by having aquatic plants (Podostemaceae) attached to the rocks, some fish were observed in low abundance (Leporinus fasciatus [Bloch, 1794], Characidium declivirostre Steindachner, 1915, Ancistrus patronus de Souza, Taphorn & Armbruster, 2019, and Hemiancistrus sp.), living in sympatry with R. Cachivera n. sp.
FIGURE 3
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Geographic distribution of Rineloricaria cachivera n. sp. in the middle río Vaupés. Black star refers to the type locality, and white circles are the paratypes. The green line highlights the Amazon basin, and the red symbols on the detailed map refer to the rapids on the río Vaupés.
FIGURE 4
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Habitat of Rineloricaria cachivera n. sp. (a) Tapira-Llerao sacred rock, (b) Raudal the Tapira-Llerao (Holotype) upstream of the Matapi indigenous community, (c) Laguna Arcoiris “small lagoon isolated from the raudal La Mojarra (paratype) upstream from the indigenous community of Matapi, (d) Raudal in the indigenous community of Trubón (paratype), and (e, f) petroglyphs in the cachiveras of the Vaupés River “Sacred sites” upstream of the Matapí indigenous community.3.9 Conservation assessmentRineloricaria cachivera n. sp. is currently known from four localities in the middle river Vaupes basin, and despite the small known distribution area (i.e., EOO: 51.752 km2/AOO: 4.000 km2), no significant threats to the species were detected. For this reason, R. cachivera can be preliminarily categorized as Least Concern (LC) according to the IUCN categories and criteria (IUCN Standards and Petitions Committee, 2022).
3.10 EtymologyThe specific name cachivera refers to a flow of water that runs violently between the rocks. In the cosmology of the indigenous peoples of the Vaupés, the waters of its rivers are inhabited by various supernatural creatures that must be venerated, consulted, and appeased in the rituals of the shamans; these creatures live and guard mainly the cachiveras of the rivers where humans are more fragile and face the greatest danger (Schultes & Raffauf, 2004) (e.g., Figure 4e,f). The species was named in memory of Javier Alejandro Maldonado-Ocampo “Nano,” who collected the new species in the cachivera of “Trubón” and “La Mojarra”; in the latter, on March 2, 2019, Nano stayed forever swimming in peace and happy with the rheophilic fish of the cachiveras of the Vaupés River.
3.11 Key to the Rineloricaria species of the Amazon River basin in Colombia1 Abdomen covered by brown dark spots; presence of dorsolateral stripes on both sides of the head.………2.
1' Abdomen without blotches and/or spots; absence of dorsolateral stripes on both sides of the head.………3.
2 Four or five premaxillary teeth; anterior abdominal plates the same size and equally numerous as central abdominal plates; anterior dorsal portion of body dark without transverse bands; two or three dark-brown narrow transverse bars restricted to the caudal peduncle.………R. jurupari (Londoño-Burbano & Urbano-Bonilla, 2018).
2' Five to eight premaxillary teeth; anterior abdominal plates smaller and more numerous than central abdominal plates; anterior dorsal portion of body with transverse band; five or six dark-brown broad transverse bars on caudal peduncle and predorsal region.………R. lanceolata (Günther, 1868).
3 Shallow posterior orbital notch; all fins (pectoral, pelvic, anal, and caudal) without a color pattern of “dark and light,” with spot occupying almost entire fin; pre-anal plate, with three polygonal scutes, of which the median one is the same size than those at either side; five series of lateral plates in longitudinal rows below the dorsal fin (Figure 5b) ………4.
FIGURE 5
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Series of lateral plates in longitudinal rows below the dorsal fin: (D) dorsal; (M-D) mid-dorsal; (M) median; (M-V) mid-ventral and (V) ventral; (LAP) lateral abdominal plates.3' Conspicuous posterior orbital notch; all fins (pectoral, pelvic, anal, and caudal) with a color pattern of “dark and light” vertical stripes; pre-anal plate, with three polygonal scutes, of which the median one is much smaller than those at either side; four series of lateral plates in longitudinal rows below the dorsal fin (Figure 5a) ………R. castroi (Isbrücker & Nijssen, 1984).
4 Six branched pectoral fin rays and lower lip surface button-like papillae.………5.
4' Seven branched pectoral fin rays and lower lip surface long finger papillae.………R. daraha (Rapp Py-Daniel & Fichberg, 2008).
5 Five dark-brown broad transverse bars on caudal peduncle and predorsal region; eye large, round to slightly oval horizontally and shallow postorbital notch; pre-anal plate with three plates surrounding the anus, one anterior and two lateral.………R. cachivera n. sp.
5' Six dark-brown broad transverse bars on caudal peduncle and predorsal region; eye large, round to slightly oval horizontally and conspicuous orbital notch; pre-anal plate, preceded by three polygonal scutes, of which the median one is much smaller than those at either side.………R. phoxocephala (Eigenmann & Eigenmann, 1889).
4 DISCUSSIONRineloricaria has not been the subject of a complete taxonomic study (neither taxonomy alpha, nor integrative taxonomy) that could offer a delimitation between valid species, and offer updated diagnostic characters for each of the species. The only phylogenetic analysis using morphological evidence, including a significant number of valid species, is the unpublished study by Fichberg (2008); even though the author found the genus as a monophyletic assemblage, the delimitation of the species remains a problem. On the contrary, Costa-Silva et al. (2015) published a work aiming at delimiting species of the genus using molecular evidence, through the COI marker. The authors found that using different species delimitation methods, different outcomes regarding the number of species were found (i.e., lineages). This result reflects what has been happening to the taxonomy of the genus, in that descriptions of new species are published often, and it appears that there is a hidden diversity of the genus, in diverse environments, far from being discovered, fully known, or understood. Finally, Covain et al. (2016) published the most comprehensive phylogenetic analysis, through molecular evidence, regarding the genus, including representatives from its entire distribution, from the trans-Andean regions to the southeast of South America, Shields, and the Amazonian region. The authors in fact divided the genus into different groups, mostly finding a component of geographic distribution for the monophyletic assemblages present within Rineloricaria. As a result, they maintained the genus as a single monophyletic unit, did not split it into different genera, and moreover synonymized several genera to Rineloricaria (i.e., Fonchiiichthys Isbrücker & Michels, 2001; Hemiloricaria Bleeker, 1862; Ixinandria Isbrücker & Nijssen, 1979; and Lelliela Isbrücker, 2001), showing how complex the level of diversity is within the genus at the phylogenetic level. The study by Covain et al. (2016) is an excellent contribution to the delimitation of the different clades found within Rineloricaria for morphological characterization. Thus, the use of molecular evidence could be the first step toward an understanding of the diversity of Rineloricaria, and the number of valid species, which is increasing, could be at least delimited at the molecular level to allow a more approachable morphological work (Costa-Silva et al., 2015).
Rineloricaria cachivera n. sp. is a clear case of the diversity of environments in which species of the genus can be found. The Vaupés River in its headwaters (i.e., Itilla and Unilla rivers) is borne in outcrops of the Craton and crosses very old rocks of the Precambrian age (Botero & Serrano, 2019). Its dark-colored waters (black-brown), acidic, with a large number of humic acids, and poor in dissolved inorganic substances, explain the low levels of nutrients (Cabalzar & Lima, 2005). The substrate is mainly sand (with beaches in the low water period) and rock (Bogotá-Gregory et al., 2022); the latter, in rocky outcrops that give way to innumerable cachiveras that serve as habitat and act as a natural barrier for fish dispersal (Lima et al., 2005). Few species belonging to Rineloricaria are found in environments with such characteristics, and one example is R. daraha, present in the Negro River basin in localities both in Brazil and Colombia. These species are not sympatric; however, they are similar morphologically and can be differentiated by the presence of six branched pectoral fin rays (vs. seven), dark spots along the dorsal portion of the body (vs. dark spots restricted to the head), and the lower lip surface with short thick papillae (vs. long finger papillae). There is also an important similarity between both species, and that is related to their rheophilic nature and the environments in which they are found. Both appear to be adapted to turbulent waters and are capable of supporting strong currents, which contain grazeable aquatic plants, algae, and invertebrates found in the holes between and on the surface of waterfall rocks (Bogotá-Gregory et al., 2016) as resources for the species. These characteristics seem to be reflected in the morphology of both species, mainly regarding head morphology. Both species have an elongated head, with a long snout, and slender bodies, especially when compared to some congeners with stockier bodies (e.g., R. misionera, R. osvaldoi Fichberg & Chamon, 2008, R. rodriguezae Costa-Silva, Oliveira & Silva 2021, Rineloricaria steinbachi [Regan 1906], Rineloricaria zawadzkii Costa-Silva, Silva & Oliveira 2022, and most southeastern and southern distributed species of the genus).
In rheophilic environments, in addition to the morphology of the head and body, loricariids develop wide mouths and thick lips with well-developed papillae that increase friction and prevent drag by the water current (Gradwell, 1971; Ono, 1980). In the lips, collagen is supposed to work to reinforce the oral suction cups and reduce slippage; furthermore, its content correlates with the substrate and the flow of water; species that live on rocky substrates and torrential water current species have larger lips, with high collagen content (Bressman et al., 2020). The Andes mountain range with its water network having innumerable rapids promoted the evolution of oral characteristics (wide mouths and thick lips with well-developed papillae) that can be observed in other genera of loricariids with restricted distribution: Andeancistrus Lujan, Meza-Vargas & Barriga Salazar 2015, Cordylancistrus Isbrücker 1980, Chaetostoma Tschudi 1846, Dolichancistrus Isbrücker 1980, Fonchiiloricaria Rodriguez, Ortega & Covain 2011, and Transancistrus Lujan, Meza-Vargas & Barriga Salazar 2015. In the genus Rineloricaria the size of the mouth, papillae, and distribution range may vary significantly (Fricke et al., 2022; van der Sleen & Albert, 2017). This is evident in some cis- and trans-Andean species, where head shape, mouth size (length/width), maxillary barbels, labial papillae, and fringes on its edge are varied and may reflect adaptations to their environment (Figure 6a–i). The species that inhabit either the rocky rapids of the Paraná sedimentary basin (Costa-Silva et al., 2021) or in drainages of the Guiana Shield in the rapids of the Vaupés-Negro River (Rapp Py-Daniel & Fichberg, 2008), including R. cachivera n. sp., R. jurupari and R. daraha, have wide and high mouths, with thick lips and well-developed papillae that may explain their rheophilic nature (Figure 6a–c), compared to species with a smaller mouth, and which have greater environmental plasticity and distribution (Figure 6d–f,i). Rapids, in addition to promoting endemism and morphological specialization of fish, limit gene flow (Lima et al., 2005; Lujan & Conway, 2015; Torrente-Vilara et al., 2011). The species adapted to these environments have restricted distributions (Bressman et al., 2020) such as R. jurupari that lives in the headwaters of the Vaupes, that is, in the Itilla and Unilla rivers (Londoño-Burbano & Urbano-Bonilla, 2018). In the middle part, R. cachivera n. sp. seems to be exclusive to the rapids of the Vaupés River, and from its type locality we recorded it to occur ~138 km upstream in the same type of environments (Figure 3). Another endemic species is R. daraha; although with a greater distribution in the basin (>700 km), it has only been recorded in rheophilic environments, that is, in the Cachiveras-Cachoeiras of the Vaupés River in Brazil and Colombia (Bogotá-Gregory et al., 2016; Rapp Py-Daniel & Fichberg, 2008). In the Amazon basin, areas of endemism have been identified (Jézéquel, Tedesco, Darwall, et al., 2020b) as basic units of analysis in historical biogeography (Morrone, 2014) and useful in conservation biology (Löwenberg-Neto & de Carvalho, 2004). The Vaupés-Negro basin, in addition to being diverse in fish, exhibits a high degree of endemism (Jézéquel, Tedesco, Darwall, et al., 2020b); consequently, identifying new species (e.g., R. jurupari and R. cachivera n. sp.) or ecosystems (e.g., Raudales-Cachiveras-Cachoeiras) as “possible” conservation targets has proven to be an effective tool for the implementation of comprehensive conservation strategies in the Amazon Colombian (Portocarrero-Aya & Cowx, 2016).
FIGURE 6
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Shape of the head, size of the mouth (length/width), maxillary barbels, labial papillae, and fringes on its edge in some Rineloricaria species. Amazon basin: (a) Rineloricaria cachivera n. sp., 114.5 mm standard length (LS) (paratype: MPUJ 14375); (b) Rineloricaria jurupari, 87.2 mm LS (holotype: MPUJ12520); (c) Rineloricaria daraha, 170 mm LS (CZUT-IC 3621); (d) Rineloricaria castroi, 109 mm LS (MPUJ 14147); Orinoco basin: (e) Rineloricaria eigenmanni, 91.7 mm LS (MPUJ 13281); (f) Rineloricaria formosa, 127.4 mm LS (MPUJ 3249); (g) Rineloricaria sp., “Orinoco,” 89.1 mm LS (MPUJ 2908); (h) Pacific and Caribbean basins: Rineloricaria jubata, 78.2 mm LS (MPUJ 11151); (i) Magdalena-Cauca and Caribbean basin: Rineloricaria magdalenae, 94.5 mm LS (MPUJ 7940). The line = 10 mm.The known diversity of Rineloricaria is growing fast, and with 71 valid species, this diversity is likely to increase. Currently, there are 11 valid species reported for Colombia, with 5 species present in the Colombian Amazon: R. castroi, R. daraha, R. phoxocephala, R. lanceolata, and R. jurupari (DoNascimiento et al., 2022), R. cachivera n. sp. being the sixth valid species recorded for the region. Of those species, one was recently recorded for Colombia (R. daraha by Bogotá-Gregory et al., 2016), and another was recently described (R. jurupari, by Londoño-Burbano & Urbano-Bonilla, 2018), summing up the species described here, that is three species recorded in less than 10 years for the same basin (i.e., Vaupés River). Furthermore, R. lanceolata is a species currently recognized as widespread along the Amazonas River basin (including the upper, middle, and lower portions of the basin, in localities of Colombia, Bolivia, Brazil, and Peru); however, from this wide distribution, a cryptic component could be present in the species. It is important to address such issues within the species as it is likely to result in several cryptic, undescribed species, and to delimit R. lanceolata to a more restricted distribution, with a better delimitation of the species (both morphological and molecular), and to understand and better describe the already great richness of Rineloricaria. This single example shows how complex the genus can be (the most diverse within Loricariinae) and adds a new component to tackle when studying its species, and the possibility of the presence of cryptic species, not only in R. lanceolata, but also for other species considered as widespread.
The description of R. cachivera n. sp. as the fourth species distributed in the Vaupés River reveals the underestimation of the diversity of Rineloricaria, which is already high as mentioned earlier. A revisionary study of the genus, delimiting the poorly characterized type species of the genus, R. lima, examination of type series and topotypic material of all valid species, and inclusion of both morphological and molecular evidence, is needed.
5 SPECIMENS EXAMINEDAll the material was examined in Londoño-Burbano and Urbano-Bonilla (2018).
6 ADDITIONAL SPECIMENS EXAMINED6.1 Rineloricaria darahaCZUT-IC 3620, Vaupés, Mpio. Yavarate, Río Papuri, comunidad de Piracuara, 0° 4′ 0″ N, 69° 33′ 28″ W; CZUT-IC 3621, Colombia, Vaupés, Mpio. Yavarate, Río Papuri, comunidad de Piracuara, 0° 4′ 11″ N, 69° 28′ 16″ W; CZUT-IC 4954, Colombia, Vaupés, Mitú, Isla Roca, 1° 11′ 29″ N, 70° 17′ 19″ W.
6.2 Rineloricaria eigenmanniMPUJ, 3281, 6, Colombia, Vichada, Puerto Carreño, Isla Santa helena, Río Orinoco, 5° 59′ 42″ N, 67° 25′ 34″ W, 17/04/2007. Col. González J.
6.3 Rineloricaria formosaZSM 25821, paratypes, 2alc, Venezuela, Orinoco River basin, Atabapo River near San Fernando 4° 03′ 0.00″ N, 67° 42′ 0.00″ W, 05/02/1973. Col: H.J. Köpcke & M. Jeschke. MPUJ 3249, 2, Colombia, Vichada, Puerto Carreño, Brazuelo Río Bita, directo al Orinoco, 6° 10′ 46″ N, 67° 38′ 0.15″ W, 10/10/2007. Col. González J.
6.4 Rineloricaria jubataBMNH 1902.5.27.45, lectotype of Loricaria jubata, Ecuador, Durango. BMNH 1901.3.29.74–76, paralectotypes, 3alc, same data as lectotype. MPUJ 11152, 1, Colombia, Valle del Cauca, Buenaventura, Corregimiento de Sabaletas, confluencia del rio Sabaletas con Río Anchicaya, 3° 44′ 23.1″ N, 76° 58′ 0.00″ W, 12/10/2014. Jorge E. García-Melo.
6.5 Rineloricaria lanceolataBMNH 1867.6.13.79, holotype of Loricaria lanceolata, Peru, Xeberos. MZUSP 81422, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, near São Pedro community, 0° 16′ 0″ N, 69° 58′ 0″ W; MZUSP 81379, Brazil, Amazonas, Negro River basin, Tiquié River, Onça stream, Onça Igarapé community, 0° 13′ 52″ N, 69° 51′ 4,9″ W; MZUSP 81439, Brazil, Amazonas, Negro River basin, Tiquié River, Caruru community, corridor above Caruru waterfall, 0° 16′ 29″ N, 69° 54′ 54″ W.
6.6 Rineloricaria magdalenaeNMW 45080, lectotype of Loricaria magdalenae, Colombia, Magdalena River basin; NMW 45800, paralectotypes, 6alc, same data as lectotype. MPUJ 7940, 3, Colombia, Antioquia, El Bagre, Quebrada El Guamo, 7° 54′ 48″ N, 74° 46′ 440″ W, 31/05/2015. Col. Jhon E. Zamudio.
Rineloricaria sp. “Orinoco”
MPUJ 2908, 3, Colombia, Meta, San Martin, Caño Camoa, 3° 39′ 47″ N, 76° 36′ 33″ W, 26/08/2017. Col. Saúl Prada-Pedreros.
6.7 Rineloricaria sp.MZUSP 64690, Brazil, Amazonas, Negro River basin, Tiquié River, São Pedro community, 0° 15′ 41″ N, 69° 57′ 23″ W; MZUSP 66145, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, tributary of Tiquié River, near São Pedro community (opposite margin), 0° 15′ 41″ N, 69° 57′ 23″ W; MZUSP 81159, Brazil, Amazonas, Negro River basin, Tiquié River, between Caruru and Boca de Sal communities, 0° 16′ 0″ N, 69° 54′ 0″ W; MZUSP 81240, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, near former São Pedro community; MZUSP 81345, Brazil, Amazonas, Negro River basin, Tiquié River, São Pedro community, Umari Norte stream, from Caruru to Cachoeira da Abelha waterfall, 0° 16′ 0″ N, 69° 58′ 0″ W; MZUSP 81417, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, near São Pedro community, 0° 16′ 0″ N, 69° 58′ 0″ W; MZUSP 81501, Brazil, Amazonas, Negro River basin, Tiquié River, São Pedro community, 0° 16′ 4″ N, 69° 58′ 21″ W; MZUSP 85099, Brazil, Amazonas, Negro River basin, Tiquié River, lower portion of Supiã stream, below Comprida waterfall, 0° 15′ N, 70° 01′ W; ZSM 27058, 4alc, Brazil, Pará, Guamá River near Ourem, Atlantic slope, 10/1988. Col: R. Stawikowski & U. Schliewen.
AUTHOR CONTRIBUTIONSInitial study design, specimen collection, and processing (A.U.B.). All authors participated equally in collection, analysis, and interpretation of data and in the preparation of the manuscript.
ACKNOWLEDGMENTSWe want to thank the support of several people from the communities of the region: William González-Torres and Arturo Hernández (Trubón community, Cubeo ethnic group), Emilio Marquez and Anderson Marquez (Villa Fátima community, Guanano ethnic group); Adelmo Santa Cruz (Nana community, Guanano ethnic group); Jaider Ramírez-Samaniego (Macucú community, Desano ethnic group), Julio V. Vélez and Silvio Vélez (Matapi community, Desano ethnic group). To Alejandro Campuzano (Fundación Conservando), Luis F. Jaramillo-Hurtado (SINCHI), and Mariana A. Moscoso (Ictiología y Cultura) for their technical support. Sandra Bibiana Correa (Mississippi State University) for her technical support and for providing data on the physicochemical aspects of water. A.U.-B. thanks the Catalog of the Fishes of Colombia, grant BID-CA2020-030-USE by GBIF, for allowing visits to some museums in the country and especially thanks curators or administrators for their unconditional support: Carlos A. García-Alzate (UARC-IC), Francisco A. Villa-Navarro (CZUT), Lauren Raz, Henry Agudelo-Zamora (ICN-MHN), Saúl Prada-Pedreros (MPUJ), Fernando Sarmiento Parra, and Julieth Stella Cárdenas Hincapié (MLS). A.L.-B. thanks James Maclaine (BMNH), Anja Palandačić (NMW), Ulrich Schliewen, Robin Böhmer, and Patricia Schulze (ZSM) for hospitality and assistance during visits to collections under their care, and Marcelo R. Britto (MNRJ) for technical and logistic support at MNRJ, where the manuscript was partially completed. Thanks to Omar Melo for help with the photographs of the holotype; Camila Castellanos, for the photo of R. daraha (Figure 6c); and Jorge García-Melo for taking photographs of live specimens in the field. Please visit the visual catalog of Colombian fish “https://cavfish.unibague.edu.co/”. Financial support was given by Pontificia Universidad Javeriana with the “Carta Encíclica Laudato Si” grant in the project entitled “Ictiología y Cultura: Aproximación biológica y cultural a los datos obtenidos en la expedición en las cachiveras del río Vaupés” (#20112). A.L.-B. was supported by a postdoctoral fellowship from FAPERJ Pós-Doutorado Nota 10 (05/2019 - E-
26/202.356/2019).
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Alexander Urbano-Bonilla, Alejandro Londoño-Burbano, Tiago P. Carvalho
First published: 10 July 2023
https://doi.org/10.1111/jfb.15500
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SHAREAbstractA new rheophilic species of the genus Rineloricaria is described for the Amazon basin in Colombia. Rineloricaria cachivera n. sp. differs from its congeners by having anterior to the first predorsal plate, an inconspicuous saddle-like mark; the presence of dark, diffuse blotches, present as unified dark colouration along most of the dorsal portion of the head, without bands or spots on the head; a long snout that occupies more than half the head length (HL), between 58.0% and 66.3% HL; a naked portion on the cleithral area from the border of lower lip reaching the origin of pectoral fin; and by having five series of lateral plates in longitudinal rows below the dorsal fin. The new species is morphologically similar to Rineloricaria daraha; however, it can be distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long finger papillae). An identification key to the Rineloricaria species of the Amazon River basin in Colombia is provided. The new species is herein categorized as Least Concern, following the IUCN criteria.
1 INTRODUCTIONThe armored catfish Rineloricaria Bleeker, 1862, has 71 valid species, being the richest genus in the family Loricariidae (Fricke et al., 2023). The genus is diagnosed by a combination of characteristics such as the presence of postorbital notch; lower lip with short round papillae; premaxilla with 7 to 15 teeth on each ramus; dentary teeth strong, deeply bicuspidate, and larger than premaxillary; colouration of the dorsal region with dark-brown bars or blotches; abdomen with a conspicuous polygonal pre-anal plate, usually bordered by three other large trapezoidal plates (Fichberg & Chamon, 2008) and some features of sexual dimorphism, which are traits not always present in the individuals available for examination (Londoño-Burbano & Urbano-Bonilla, 2018). Progress has been made in the taxonomic and phylogenetic relationships between Rineloricaria species (Covain & Fisch-Muller, 2007), and it is now demonstrated to be a monophyletic group based on molecular data (Costa-Silva et al., 2015; Covain et al., 2016) with wide interspecies morphological variation (e.g., body color and shape, arrangement of abdominal plates, shape of head, and distribution of hypertrophied odontodes; Vera-Alcaraz et al., 2012).
The wide distribution of Rineloricaria in the main Neotropical basins and environments reflects the diversity and morphological adaptations of its species (van der Sleen & Albert, 2017; Vera-Alcaraz et al., 2012). Some species occur in small drainages of slow to moderate-flowing waters, associated with sand, vegetation, and organic matter; others are rheophilic inhabiting fast-flowing rivers associated with rocks (Costa-Silva et al., 2021; Lima et al., 2005; Londoño-Burbano & Urbano-Bonilla, 2018; Rapp Py-Daniel & Fichberg, 2008; Rodriguez & Reis, 2008). Rheophilic environments have driven the evolution of armored catfish lineages in the family Loricariidae (Lujan & Conway, 2015); the rheophilic species of Rineloricaria exhibit consistent ecomorphological patterns and that is evidenced in the shape of the body, mouth, and buccal papillae (Bressman et al., 2020).
In Colombia, 11 species are present in different hydrographic basins: Pacific and Caribbean: Rineloricaria jubata (Boulenger 1902); Pacific: Rineloricaria sneiderni (Fowler 1944); Caribbean Rineloricaria rupestris (Schultz 1944) and Magdalena-Cauca and Caribbean: Rineloricaria magdalenae (Steindachner 1879); Orinoco: Rineloricaria eigenmanni (Pellegrin 1908) and Rineloricaria formosa Isbrücker & Nijssen 1979; Amazonas: Rineloricaria castroi Isbrücker & Nijssen 1984, Rineloricaria daraha Rapp Py-Daniel & Fichberg, 2008, Rineloricaria phoxocephala (Eigenmann & Eigenmann 1889), Rineloricaria lanceolata (Günther 1868) and Rineloricaria jurupari Londoño-Burbano & Urbano-Bonilla, 2018 (DoNascimiento et al., 2021). The diversity of species in Colombia may have been underestimated due to a lack of data and sampling, especially in the Amazon basin (Jézéquel, Tedesco, Bigorne, et al., 2020a). Of the main rivers that drain to the Amazon (e.g., in Colombia: Caquetá, Putumayo, Apaporis, and Vaupés), the Vaupés is located in a Miocene Andean tectonic upheaval known as the Vaupés Arch (10 Ma), which acts as a semi-permeable barrier for the dispersal of fish (Winemiler & Willis, 2011) dividing the Amazon and Orinoco basins (Mora et al., 2010). Located on its border with Brazil, this river has numerous rocky rapids (locally known as “Cachiveras,” or “Raudales”) along its course that serve as a habitat and act as hydrogeographic barriers for fish. In the exploration of these environments, a new species of the genus Rineloricaria was identified, and it is described herein. Additionally, an updated identification key for species present at the Colombian Amazon is provided.
2 MATERIALS AND METHODSFish collection follows animal care guidelines provided by the American Society of Ichthyologists and Herpetologists (2013) -https://www.asih.org/resources. The biological material of MPUJ collected in this expedition in the río Vaupés went through a process of amnesty by the Instituto de Investigación Alexander von Humboldt under Colombian law “article 6 of law 1955 of 2019.” Fishes were captured using hand-nets or hand-captured by active snorkeling dives in polls or rapids of the Vaupés River. Specimens were photographed in life following the scientific documentation protocols of Photafish (Garcia-Melo et al., 2019). The holotype was also photographed in the laboratory following similar protocols. When the collected specimens were euthanized, doses of 0.3 mL/0.25 L of clove oil were added (Syzygium aromaticum; Lucena et al., 2013) before fixation. Fishes were fixed in 10% formaldehyde and later preserved in 70% ethanol for storage. Counts and measurements were made on the left side of specimens when possible, using digital calipers to the nearest 0.1 mm. Measurement, plate series count, and nomenclature followed Vera-Alcaraz et al. (2012). The terms “main cusp” and “lateral cusp” follow Muller and Weber (1992). Institutional acronyms follow Sabaj (2020). Characteristics used to diagnose the new species from species that are not included in the item “Additional specimens examined” were analysed and compared using original and subsequent descriptions of each species. In the description, counts are followed by their frequency in parentheses, and an asterisk (*) indicates the count of the holotype. Conservation Assessment Tool-GeoCAT was used to assess the geographic range of the taxon in two approaches: (i) extent of occurrence (EOO) and (ii) area of occupancy (AOO). Both metrics are part of the IUCN Red List categories and criteria (IUCN Subcommittee on Standards and Petitions, 2022). This study adjusted the grid to 1 km2, following the criteria of Bachman et al. (2011) for aquatic ecosystems.
3 RESULTS3.1 R. cachivera new speciesurn:lsid:zoobank.org:pub:7E3CCD7A-6118-4D3C-ADD1-F89A06ADF735.
urn:lsid:zoobank.org:act:FA5DEFCE-5666-46DD-9D3E-1F6E8E138668.
(Figures 1 and 2; and Table 1).
FIGURE 1
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Holotype of Rineloricaria cachivera n. sp., MPUJ 14451, 122.8 mm standard length (LS), río Vaupés upstream Cachivera Tapira-llerao, Comunidad de Matapí, Mitú, Vaupés, Colombia.
FIGURE 2
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Paratypes of Rineloricaria cachivera n. sp. (a) Unpreserved specimen, río Vaupés at Resguardo Trubón. (b-c) MPUJ 14481, 114.4 mm standard length (LS), río Vaupés at Laguna Arcoiris small rocky bottom isolated lagoon from the river, Comunidad de Matapí, Mitú, Vaupés, Colombia.
TABLE 1. Morphometric data of holotype (H) and paratypes of Rineloricaria cachivera n. sp. (n = 4 including the holotype).
HolotypeMinimumMaximumMeanS.D.Standard length122.877.2122.8107.2-
Percentage of standard length
Head length24.721.925.124.11.48
Predorsal length37.137.137.837.40.33
Postdorsal length62.262.265.463.91.30
Prepectoral length22.421.322.421.80.48
Postpectoral length82.180.284.382.31.66
Prepelvic length36.036.036.736.30.28
Postpelvic length65.565.466.765.80.61
Pre-anal length50.950.051.450.90.62
Postanal length50.347.250.349.21.41
Unbranched dorsal-fin ray19.417.020.919.41.67
Unbranched pectoral-fin ray17.717.820.619.01.18
Unbranched pelvic-fin ray18.318.319.318.90.42
Unbranched anal-fin ray17.717.720.619.41.26
Thoracic length16.715.818.016.70.92
Abdominal length17.016.217.817.10.71
Cleithral width19.619.620.619.90.47
Depth at dorsal-fin origin13.311.314.412.61.45
Width at anal-fin origin14.713.115.014.20.89
Caudal peduncle depth1.51.41.71.50.11
Caudal peduncle width2.72.73.23.00.24
Percentage of head length
Snout length58.058.066.360.43.96
Eye diameter10.210.213.011.21.22
Maximum orbital diameter14.513.218.315.22.19
Interorbital width25.023.329.025.42.47
Internarial width9.69.615.411.82.73
Head depth44.836.251.543.26.54
Head width76.473.593.581.58.82
Free maxillary barbel5.65.38.36.61.42
Ventrorostral length9.98.310.59.60.94
Lower lip length22.420.123.721.81.57
- Abbreviation: S.D., standard deviation.
3.3 ParatypesMPUJ 14375, 114.5, mm LS. Colombia, Vaupés Department, Mitú municipality, Negro River drainage, río Vaupés at Resguardo Trubón, 1° 12′ 8.38″ N, 70° 2′ 20.67″ W, 176 m a.s.l., coll, J. A. Maldonado-Ocampo et al., February 22, 2019. MPUJ 14481, 114.4 mm LS, Colombia, Vaupés Department, Mitú municipality, Negro River drainage, río Vaupés, Laguna Arcoiris small rocky bottom isolated lagoon from the river, Comunidad de Matapí, 1° 4′ 48.30″ 14495, 77.2 mm LS Colombia, Vaupés Department, Mitú municipality, Negro River drainage, río Vaupés at Comunidad de Matapí, 1° 4′ 49.16″ N, 69° 21′ 50.44″ W, 119 m a.s.l., coll, J. A. Maldonado-Ocampo et al., March 2, 2019.
3.4 DiagnosisThe new species differs from all its congeners by the following combination of characters: presence of a transverse dorsal band that is not well defined and is curved, similar to that band observed on anterior border of snout, anterior to the first predorsal plate (vs. transversal band absent; when present, first dorsal transversal band well defined, straight, not curved); presence of dark, diffuse blotches, present as unified dark colouration along most of dorsal portion of head, without bands or spots on head (vs. absence of dark, diffuse blotches, present as unified dark colouration along most of dorsal portion of head, without bands or spots on head); a long snout that occupies more than half the HL, between 58.0% and 66.3% HL (vs. short snout, occupying half or less than half of HL, usually less than 56% HL; except in R. daraha, R. lanceolata, R. malabarbai Rodriguez & Reis, 2008, Rineloricaria microlepidogaster [Regan 1904], and Rineloricaria osvaldoi Fichberg & Chamon, 2008); and naked portion on the cleithral region from border of lower lip reaching origin of pectoral fin (vs. naked portion of cleithral region not reaching origin of pectoral fin, beyond pectoral-fin origin, or portion totally covered by plates). Rineloricaria cachivera n. sp. is further distinguished by having five series of lateral plates in longitudinal rows below the dorsal fin (vs. four series of lateral plates in longitudinal rows below the dorsal fin in R. aurata (Knaack 2002), Rineloricaria beni (Pearson 1924), Rineloricaria cadeae (Hensel 1868), R. castroi, Rineloricaria catamarcensis (Berg 1895), Rineloricaria cubatonis (Steindachner 1907), Rineloricaria felipponei (Fowler 1943), Rineloricaria henselli (Steindachner 1907), R. jurupari, R. lanceolata, Rineloricaria langei Ingenito, Ghazzi, Duboc & Abilhoa 2008, Rineloricaria lima (Kner 1853), Rineloricaria longicauda Reis 1983, Rineloricaria magdalenae, Rineloricaria microlepidota (Steindachner 1907), Rineloricaria misionera Rodriguez & Miquelarena, 2005, Rineloricaria nigricauda (Regan 1904), Rineloricaria pareiacantha Mirande & Koerber 2015, Rineloricaria parva (Boulenger 1895), Rineloricaria quadrensis Reis 1983, Rineloricaria sanga Ghazzi 2008, Rineloricaria setepovos Ghazzi 2008, Rineloricaria sneiderni, Rineloricaria stellata Ghazzi 2008, Rineloricaria thrissoceps (Fowler 1943), Rineloricaria uracantha (Kner 1863), and Rineloricaria wolfei Fowler 1940). The new species is morphologically similar to R. daraha, a congener distributed in the río Negro basin (Brazil and Colombia); however, it can be easily distinguished by the presence of six branched pectoral fin rays (vs. seven) and the lower lip surface with short thick papillae (vs. long papillae).
3.5 DescriptionMorphometric data in Table 1. Largest specimen reaching 122.8 mm LS. Snout straight in lateral view, slightly raised on its tip. Dorsal profile straight to slightly convex from orbits to nuchal plate, and straight from dorsal origin to base of caudal-fin origin. Ventral profile of head straight; convex from anterior abdominal plates to anal-fin base, straight from that point to caudal-fin origin. Body and head wide, widening strongly at about origin of first infraorbital. Posterior portion of body with a noticeable narrowing at about half length of caudal peduncle. Five plates in infraorbital series, with sensory pores exposed ventrally. Snout tip with large oval naked area, but not extending laterally surpassing sensorial pore of first infraorbital. Poorly developed odontodes on head and trunk. Dorsum of head smooth, not presenting ridges on head and predorsal plates. Posterior margin of parieto-supraoccipital triangular. Dorsal margin of orbit not raised; postorbital notch shallow, not well developed. Eye large, round to slightly oval horizontally. Lower lip large, almost reaching anterior limit of abdominal plates, with lower border covered by 10 to 12 fringes on margin of each lobe. Round papillae covering lower lip, increasing in size toward dentary ramii, a line of more developed papillae near line with maxillary barbel. Teeth bicuspid, long, main cusp greater and wider than lateral, dentary teeth larger than premaxillary teeth, main cusp about twice length of lateral cusp. Premaxilla with 6(3*) or 8(1) teeth; dentary with 5(1*), 6(1), 7(1), 8(1) teeth. Five lateral plate series. Median lateral plates 27(2), or 28(2*). Lateral line complete. Lateral abdominal plates 9(2), 10(1), or 11(1*). Central abdominal plates well developed, slightly smaller anteriorly, having about 4–5 rows irregularly distributed. Abdominal plates covering entire abdomen, without naked areas. Posterior abdominal plates surrounding a well-defined pre-anal area, with three plates surrounding anus, one anterior and two lateral. Anterior margin of anterior abdominal plates slightly rounded or concave on its central portion. Dorsal fin I,7(4), dorsal-fin spinelet present, locking mechanism not functional; tip of depressed unbranched ray reaching fourth or fifth plate posterior to dorsal-fin base; tip of depressed last branched ray reaching third or fourth plate; distal margin falcate with unbranched and first branched rays longer than remaining, dorsal-fin base occupying 4(4) plates; pectoral fin I,6(4); tip of depressed unbranched ray reaching and slightly surpassing dorsal-fin origin; distal margin truncate. Pelvic fin i,5 (4), depressed unbranched ray slightly surpassing anal-fin origin. Anal fin i,5(4), with tip of depressed unbranched ray reaching sixth plate posterior to its base, depressed last branched ray reaching third or fourth plate posterior to its base; anal-fin base with three plates; distal margin truncate. Caudal fin emarginate, i,10,i (3) and i,9,i(2*); dorsal principal ray extended as long filament, filament about 2−4 times length of lower unbranched one (Figure 2a).
3.6 ColourationOverall ground colouration yellowish, presenting dark-brown portions, especially on dorsal surface (Figure 1). Dorsal surface of body mostly yellowish contrasting with darker saddle-like pigmentation areas, ventral portion of body lighter. Dorsal body with five wide saddle-like dark marks; first one at base of dorsal fin, second starting just posterior to end of adnate last branched dorsal-fin ray and three marks between adnate end of anal fin and caudal peduncle. Lighter areas between dark saddles presenting dark scattered spots. Posterior region of parieto-supraoccipital darker with an inconspicuous saddle-like mark; ventral surface of head light yellowish with dark spots on cheek plates and snout area. Dark-brown irregular spots covering the lateral margin of abdomen, the remaining portion with yellow ground colouration (Figures 1 and 2). All fins with a dark band occupying almost their entire surfaces. Colouration in life similar as in preserved specimens except for brighter yellowish ground colouration (Figure 2).
3.7 Sexual dimorphismIn adult males, the first ray (unbranched) of pelvic fins has an extension equal in width to the rest of the ray; it is filament-shaped but very thick (Figure 2a; this individual was lost in the expedition accident and the photograph).
3.8 Distribution, habitat, and physicochemistry of waterRineloricaria cachivera n. sp. is known from four localities in the middle Vaupés River, downstream from the municipality of Mitú in Colombia (Figures 3 and 4a–d). With dark waters, little transparency (Secci disk values: x˙116 ± 11.31 S.D. and x˙122.50 ± 10.61 S.D.), and deep zones in the area of the rapids (up to 18.6 m). The mean values with standard deviation (mean ± S.D.) of the temperature (28.15 ± 0.21°C–29.65 ± 0.21°C), dissolved oxygen in the water (7.63 mg/L ± 0.25) and the surface (6.41 mg/L ± 0.01) are variable. In subaquatic dives with a diving mask, the specimens were collected by hand. In these rheophilic environments that are characterized by having aquatic plants (Podostemaceae) attached to the rocks, some fish were observed in low abundance (Leporinus fasciatus [Bloch, 1794], Characidium declivirostre Steindachner, 1915, Ancistrus patronus de Souza, Taphorn & Armbruster, 2019, and Hemiancistrus sp.), living in sympatry with R. Cachivera n. sp.
FIGURE 3
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Geographic distribution of Rineloricaria cachivera n. sp. in the middle río Vaupés. Black star refers to the type locality, and white circles are the paratypes. The green line highlights the Amazon basin, and the red symbols on the detailed map refer to the rapids on the río Vaupés.
FIGURE 4
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Habitat of Rineloricaria cachivera n. sp. (a) Tapira-Llerao sacred rock, (b) Raudal the Tapira-Llerao (Holotype) upstream of the Matapi indigenous community, (c) Laguna Arcoiris “small lagoon isolated from the raudal La Mojarra (paratype) upstream from the indigenous community of Matapi, (d) Raudal in the indigenous community of Trubón (paratype), and (e, f) petroglyphs in the cachiveras of the Vaupés River “Sacred sites” upstream of the Matapí indigenous community.3.9 Conservation assessmentRineloricaria cachivera n. sp. is currently known from four localities in the middle river Vaupes basin, and despite the small known distribution area (i.e., EOO: 51.752 km2/AOO: 4.000 km2), no significant threats to the species were detected. For this reason, R. cachivera can be preliminarily categorized as Least Concern (LC) according to the IUCN categories and criteria (IUCN Standards and Petitions Committee, 2022).
3.10 EtymologyThe specific name cachivera refers to a flow of water that runs violently between the rocks. In the cosmology of the indigenous peoples of the Vaupés, the waters of its rivers are inhabited by various supernatural creatures that must be venerated, consulted, and appeased in the rituals of the shamans; these creatures live and guard mainly the cachiveras of the rivers where humans are more fragile and face the greatest danger (Schultes & Raffauf, 2004) (e.g., Figure 4e,f). The species was named in memory of Javier Alejandro Maldonado-Ocampo “Nano,” who collected the new species in the cachivera of “Trubón” and “La Mojarra”; in the latter, on March 2, 2019, Nano stayed forever swimming in peace and happy with the rheophilic fish of the cachiveras of the Vaupés River.
3.11 Key to the Rineloricaria species of the Amazon River basin in Colombia1 Abdomen covered by brown dark spots; presence of dorsolateral stripes on both sides of the head.………2.
1' Abdomen without blotches and/or spots; absence of dorsolateral stripes on both sides of the head.………3.
2 Four or five premaxillary teeth; anterior abdominal plates the same size and equally numerous as central abdominal plates; anterior dorsal portion of body dark without transverse bands; two or three dark-brown narrow transverse bars restricted to the caudal peduncle.………R. jurupari (Londoño-Burbano & Urbano-Bonilla, 2018).
2' Five to eight premaxillary teeth; anterior abdominal plates smaller and more numerous than central abdominal plates; anterior dorsal portion of body with transverse band; five or six dark-brown broad transverse bars on caudal peduncle and predorsal region.………R. lanceolata (Günther, 1868).
3 Shallow posterior orbital notch; all fins (pectoral, pelvic, anal, and caudal) without a color pattern of “dark and light,” with spot occupying almost entire fin; pre-anal plate, with three polygonal scutes, of which the median one is the same size than those at either side; five series of lateral plates in longitudinal rows below the dorsal fin (Figure 5b) ………4.
FIGURE 5
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Series of lateral plates in longitudinal rows below the dorsal fin: (D) dorsal; (M-D) mid-dorsal; (M) median; (M-V) mid-ventral and (V) ventral; (LAP) lateral abdominal plates.3' Conspicuous posterior orbital notch; all fins (pectoral, pelvic, anal, and caudal) with a color pattern of “dark and light” vertical stripes; pre-anal plate, with three polygonal scutes, of which the median one is much smaller than those at either side; four series of lateral plates in longitudinal rows below the dorsal fin (Figure 5a) ………R. castroi (Isbrücker & Nijssen, 1984).
4 Six branched pectoral fin rays and lower lip surface button-like papillae.………5.
4' Seven branched pectoral fin rays and lower lip surface long finger papillae.………R. daraha (Rapp Py-Daniel & Fichberg, 2008).
5 Five dark-brown broad transverse bars on caudal peduncle and predorsal region; eye large, round to slightly oval horizontally and shallow postorbital notch; pre-anal plate with three plates surrounding the anus, one anterior and two lateral.………R. cachivera n. sp.
5' Six dark-brown broad transverse bars on caudal peduncle and predorsal region; eye large, round to slightly oval horizontally and conspicuous orbital notch; pre-anal plate, preceded by three polygonal scutes, of which the median one is much smaller than those at either side.………R. phoxocephala (Eigenmann & Eigenmann, 1889).
4 DISCUSSIONRineloricaria has not been the subject of a complete taxonomic study (neither taxonomy alpha, nor integrative taxonomy) that could offer a delimitation between valid species, and offer updated diagnostic characters for each of the species. The only phylogenetic analysis using morphological evidence, including a significant number of valid species, is the unpublished study by Fichberg (2008); even though the author found the genus as a monophyletic assemblage, the delimitation of the species remains a problem. On the contrary, Costa-Silva et al. (2015) published a work aiming at delimiting species of the genus using molecular evidence, through the COI marker. The authors found that using different species delimitation methods, different outcomes regarding the number of species were found (i.e., lineages). This result reflects what has been happening to the taxonomy of the genus, in that descriptions of new species are published often, and it appears that there is a hidden diversity of the genus, in diverse environments, far from being discovered, fully known, or understood. Finally, Covain et al. (2016) published the most comprehensive phylogenetic analysis, through molecular evidence, regarding the genus, including representatives from its entire distribution, from the trans-Andean regions to the southeast of South America, Shields, and the Amazonian region. The authors in fact divided the genus into different groups, mostly finding a component of geographic distribution for the monophyletic assemblages present within Rineloricaria. As a result, they maintained the genus as a single monophyletic unit, did not split it into different genera, and moreover synonymized several genera to Rineloricaria (i.e., Fonchiiichthys Isbrücker & Michels, 2001; Hemiloricaria Bleeker, 1862; Ixinandria Isbrücker & Nijssen, 1979; and Lelliela Isbrücker, 2001), showing how complex the level of diversity is within the genus at the phylogenetic level. The study by Covain et al. (2016) is an excellent contribution to the delimitation of the different clades found within Rineloricaria for morphological characterization. Thus, the use of molecular evidence could be the first step toward an understanding of the diversity of Rineloricaria, and the number of valid species, which is increasing, could be at least delimited at the molecular level to allow a more approachable morphological work (Costa-Silva et al., 2015).
Rineloricaria cachivera n. sp. is a clear case of the diversity of environments in which species of the genus can be found. The Vaupés River in its headwaters (i.e., Itilla and Unilla rivers) is borne in outcrops of the Craton and crosses very old rocks of the Precambrian age (Botero & Serrano, 2019). Its dark-colored waters (black-brown), acidic, with a large number of humic acids, and poor in dissolved inorganic substances, explain the low levels of nutrients (Cabalzar & Lima, 2005). The substrate is mainly sand (with beaches in the low water period) and rock (Bogotá-Gregory et al., 2022); the latter, in rocky outcrops that give way to innumerable cachiveras that serve as habitat and act as a natural barrier for fish dispersal (Lima et al., 2005). Few species belonging to Rineloricaria are found in environments with such characteristics, and one example is R. daraha, present in the Negro River basin in localities both in Brazil and Colombia. These species are not sympatric; however, they are similar morphologically and can be differentiated by the presence of six branched pectoral fin rays (vs. seven), dark spots along the dorsal portion of the body (vs. dark spots restricted to the head), and the lower lip surface with short thick papillae (vs. long finger papillae). There is also an important similarity between both species, and that is related to their rheophilic nature and the environments in which they are found. Both appear to be adapted to turbulent waters and are capable of supporting strong currents, which contain grazeable aquatic plants, algae, and invertebrates found in the holes between and on the surface of waterfall rocks (Bogotá-Gregory et al., 2016) as resources for the species. These characteristics seem to be reflected in the morphology of both species, mainly regarding head morphology. Both species have an elongated head, with a long snout, and slender bodies, especially when compared to some congeners with stockier bodies (e.g., R. misionera, R. osvaldoi Fichberg & Chamon, 2008, R. rodriguezae Costa-Silva, Oliveira & Silva 2021, Rineloricaria steinbachi [Regan 1906], Rineloricaria zawadzkii Costa-Silva, Silva & Oliveira 2022, and most southeastern and southern distributed species of the genus).
In rheophilic environments, in addition to the morphology of the head and body, loricariids develop wide mouths and thick lips with well-developed papillae that increase friction and prevent drag by the water current (Gradwell, 1971; Ono, 1980). In the lips, collagen is supposed to work to reinforce the oral suction cups and reduce slippage; furthermore, its content correlates with the substrate and the flow of water; species that live on rocky substrates and torrential water current species have larger lips, with high collagen content (Bressman et al., 2020). The Andes mountain range with its water network having innumerable rapids promoted the evolution of oral characteristics (wide mouths and thick lips with well-developed papillae) that can be observed in other genera of loricariids with restricted distribution: Andeancistrus Lujan, Meza-Vargas & Barriga Salazar 2015, Cordylancistrus Isbrücker 1980, Chaetostoma Tschudi 1846, Dolichancistrus Isbrücker 1980, Fonchiiloricaria Rodriguez, Ortega & Covain 2011, and Transancistrus Lujan, Meza-Vargas & Barriga Salazar 2015. In the genus Rineloricaria the size of the mouth, papillae, and distribution range may vary significantly (Fricke et al., 2022; van der Sleen & Albert, 2017). This is evident in some cis- and trans-Andean species, where head shape, mouth size (length/width), maxillary barbels, labial papillae, and fringes on its edge are varied and may reflect adaptations to their environment (Figure 6a–i). The species that inhabit either the rocky rapids of the Paraná sedimentary basin (Costa-Silva et al., 2021) or in drainages of the Guiana Shield in the rapids of the Vaupés-Negro River (Rapp Py-Daniel & Fichberg, 2008), including R. cachivera n. sp., R. jurupari and R. daraha, have wide and high mouths, with thick lips and well-developed papillae that may explain their rheophilic nature (Figure 6a–c), compared to species with a smaller mouth, and which have greater environmental plasticity and distribution (Figure 6d–f,i). Rapids, in addition to promoting endemism and morphological specialization of fish, limit gene flow (Lima et al., 2005; Lujan & Conway, 2015; Torrente-Vilara et al., 2011). The species adapted to these environments have restricted distributions (Bressman et al., 2020) such as R. jurupari that lives in the headwaters of the Vaupes, that is, in the Itilla and Unilla rivers (Londoño-Burbano & Urbano-Bonilla, 2018). In the middle part, R. cachivera n. sp. seems to be exclusive to the rapids of the Vaupés River, and from its type locality we recorded it to occur ~138 km upstream in the same type of environments (Figure 3). Another endemic species is R. daraha; although with a greater distribution in the basin (>700 km), it has only been recorded in rheophilic environments, that is, in the Cachiveras-Cachoeiras of the Vaupés River in Brazil and Colombia (Bogotá-Gregory et al., 2016; Rapp Py-Daniel & Fichberg, 2008). In the Amazon basin, areas of endemism have been identified (Jézéquel, Tedesco, Darwall, et al., 2020b) as basic units of analysis in historical biogeography (Morrone, 2014) and useful in conservation biology (Löwenberg-Neto & de Carvalho, 2004). The Vaupés-Negro basin, in addition to being diverse in fish, exhibits a high degree of endemism (Jézéquel, Tedesco, Darwall, et al., 2020b); consequently, identifying new species (e.g., R. jurupari and R. cachivera n. sp.) or ecosystems (e.g., Raudales-Cachiveras-Cachoeiras) as “possible” conservation targets has proven to be an effective tool for the implementation of comprehensive conservation strategies in the Amazon Colombian (Portocarrero-Aya & Cowx, 2016).
FIGURE 6
Open in figure viewerPowerPoint
Shape of the head, size of the mouth (length/width), maxillary barbels, labial papillae, and fringes on its edge in some Rineloricaria species. Amazon basin: (a) Rineloricaria cachivera n. sp., 114.5 mm standard length (LS) (paratype: MPUJ 14375); (b) Rineloricaria jurupari, 87.2 mm LS (holotype: MPUJ12520); (c) Rineloricaria daraha, 170 mm LS (CZUT-IC 3621); (d) Rineloricaria castroi, 109 mm LS (MPUJ 14147); Orinoco basin: (e) Rineloricaria eigenmanni, 91.7 mm LS (MPUJ 13281); (f) Rineloricaria formosa, 127.4 mm LS (MPUJ 3249); (g) Rineloricaria sp., “Orinoco,” 89.1 mm LS (MPUJ 2908); (h) Pacific and Caribbean basins: Rineloricaria jubata, 78.2 mm LS (MPUJ 11151); (i) Magdalena-Cauca and Caribbean basin: Rineloricaria magdalenae, 94.5 mm LS (MPUJ 7940). The line = 10 mm.The known diversity of Rineloricaria is growing fast, and with 71 valid species, this diversity is likely to increase. Currently, there are 11 valid species reported for Colombia, with 5 species present in the Colombian Amazon: R. castroi, R. daraha, R. phoxocephala, R. lanceolata, and R. jurupari (DoNascimiento et al., 2022), R. cachivera n. sp. being the sixth valid species recorded for the region. Of those species, one was recently recorded for Colombia (R. daraha by Bogotá-Gregory et al., 2016), and another was recently described (R. jurupari, by Londoño-Burbano & Urbano-Bonilla, 2018), summing up the species described here, that is three species recorded in less than 10 years for the same basin (i.e., Vaupés River). Furthermore, R. lanceolata is a species currently recognized as widespread along the Amazonas River basin (including the upper, middle, and lower portions of the basin, in localities of Colombia, Bolivia, Brazil, and Peru); however, from this wide distribution, a cryptic component could be present in the species. It is important to address such issues within the species as it is likely to result in several cryptic, undescribed species, and to delimit R. lanceolata to a more restricted distribution, with a better delimitation of the species (both morphological and molecular), and to understand and better describe the already great richness of Rineloricaria. This single example shows how complex the genus can be (the most diverse within Loricariinae) and adds a new component to tackle when studying its species, and the possibility of the presence of cryptic species, not only in R. lanceolata, but also for other species considered as widespread.
The description of R. cachivera n. sp. as the fourth species distributed in the Vaupés River reveals the underestimation of the diversity of Rineloricaria, which is already high as mentioned earlier. A revisionary study of the genus, delimiting the poorly characterized type species of the genus, R. lima, examination of type series and topotypic material of all valid species, and inclusion of both morphological and molecular evidence, is needed.
5 SPECIMENS EXAMINEDAll the material was examined in Londoño-Burbano and Urbano-Bonilla (2018).
6 ADDITIONAL SPECIMENS EXAMINED6.1 Rineloricaria darahaCZUT-IC 3620, Vaupés, Mpio. Yavarate, Río Papuri, comunidad de Piracuara, 0° 4′ 0″ N, 69° 33′ 28″ W; CZUT-IC 3621, Colombia, Vaupés, Mpio. Yavarate, Río Papuri, comunidad de Piracuara, 0° 4′ 11″ N, 69° 28′ 16″ W; CZUT-IC 4954, Colombia, Vaupés, Mitú, Isla Roca, 1° 11′ 29″ N, 70° 17′ 19″ W.
6.2 Rineloricaria eigenmanniMPUJ, 3281, 6, Colombia, Vichada, Puerto Carreño, Isla Santa helena, Río Orinoco, 5° 59′ 42″ N, 67° 25′ 34″ W, 17/04/2007. Col. González J.
6.3 Rineloricaria formosaZSM 25821, paratypes, 2alc, Venezuela, Orinoco River basin, Atabapo River near San Fernando 4° 03′ 0.00″ N, 67° 42′ 0.00″ W, 05/02/1973. Col: H.J. Köpcke & M. Jeschke. MPUJ 3249, 2, Colombia, Vichada, Puerto Carreño, Brazuelo Río Bita, directo al Orinoco, 6° 10′ 46″ N, 67° 38′ 0.15″ W, 10/10/2007. Col. González J.
6.4 Rineloricaria jubataBMNH 1902.5.27.45, lectotype of Loricaria jubata, Ecuador, Durango. BMNH 1901.3.29.74–76, paralectotypes, 3alc, same data as lectotype. MPUJ 11152, 1, Colombia, Valle del Cauca, Buenaventura, Corregimiento de Sabaletas, confluencia del rio Sabaletas con Río Anchicaya, 3° 44′ 23.1″ N, 76° 58′ 0.00″ W, 12/10/2014. Jorge E. García-Melo.
6.5 Rineloricaria lanceolataBMNH 1867.6.13.79, holotype of Loricaria lanceolata, Peru, Xeberos. MZUSP 81422, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, near São Pedro community, 0° 16′ 0″ N, 69° 58′ 0″ W; MZUSP 81379, Brazil, Amazonas, Negro River basin, Tiquié River, Onça stream, Onça Igarapé community, 0° 13′ 52″ N, 69° 51′ 4,9″ W; MZUSP 81439, Brazil, Amazonas, Negro River basin, Tiquié River, Caruru community, corridor above Caruru waterfall, 0° 16′ 29″ N, 69° 54′ 54″ W.
6.6 Rineloricaria magdalenaeNMW 45080, lectotype of Loricaria magdalenae, Colombia, Magdalena River basin; NMW 45800, paralectotypes, 6alc, same data as lectotype. MPUJ 7940, 3, Colombia, Antioquia, El Bagre, Quebrada El Guamo, 7° 54′ 48″ N, 74° 46′ 440″ W, 31/05/2015. Col. Jhon E. Zamudio.
Rineloricaria sp. “Orinoco”
MPUJ 2908, 3, Colombia, Meta, San Martin, Caño Camoa, 3° 39′ 47″ N, 76° 36′ 33″ W, 26/08/2017. Col. Saúl Prada-Pedreros.
6.7 Rineloricaria sp.MZUSP 64690, Brazil, Amazonas, Negro River basin, Tiquié River, São Pedro community, 0° 15′ 41″ N, 69° 57′ 23″ W; MZUSP 66145, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, tributary of Tiquié River, near São Pedro community (opposite margin), 0° 15′ 41″ N, 69° 57′ 23″ W; MZUSP 81159, Brazil, Amazonas, Negro River basin, Tiquié River, between Caruru and Boca de Sal communities, 0° 16′ 0″ N, 69° 54′ 0″ W; MZUSP 81240, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, near former São Pedro community; MZUSP 81345, Brazil, Amazonas, Negro River basin, Tiquié River, São Pedro community, Umari Norte stream, from Caruru to Cachoeira da Abelha waterfall, 0° 16′ 0″ N, 69° 58′ 0″ W; MZUSP 81417, Brazil, Amazonas, Negro River basin, Tiquié River, Açaí stream, near São Pedro community, 0° 16′ 0″ N, 69° 58′ 0″ W; MZUSP 81501, Brazil, Amazonas, Negro River basin, Tiquié River, São Pedro community, 0° 16′ 4″ N, 69° 58′ 21″ W; MZUSP 85099, Brazil, Amazonas, Negro River basin, Tiquié River, lower portion of Supiã stream, below Comprida waterfall, 0° 15′ N, 70° 01′ W; ZSM 27058, 4alc, Brazil, Pará, Guamá River near Ourem, Atlantic slope, 10/1988. Col: R. Stawikowski & U. Schliewen.
AUTHOR CONTRIBUTIONSInitial study design, specimen collection, and processing (A.U.B.). All authors participated equally in collection, analysis, and interpretation of data and in the preparation of the manuscript.
ACKNOWLEDGMENTSWe want to thank the support of several people from the communities of the region: William González-Torres and Arturo Hernández (Trubón community, Cubeo ethnic group), Emilio Marquez and Anderson Marquez (Villa Fátima community, Guanano ethnic group); Adelmo Santa Cruz (Nana community, Guanano ethnic group); Jaider Ramírez-Samaniego (Macucú community, Desano ethnic group), Julio V. Vélez and Silvio Vélez (Matapi community, Desano ethnic group). To Alejandro Campuzano (Fundación Conservando), Luis F. Jaramillo-Hurtado (SINCHI), and Mariana A. Moscoso (Ictiología y Cultura) for their technical support. Sandra Bibiana Correa (Mississippi State University) for her technical support and for providing data on the physicochemical aspects of water. A.U.-B. thanks the Catalog of the Fishes of Colombia, grant BID-CA2020-030-USE by GBIF, for allowing visits to some museums in the country and especially thanks curators or administrators for their unconditional support: Carlos A. García-Alzate (UARC-IC), Francisco A. Villa-Navarro (CZUT), Lauren Raz, Henry Agudelo-Zamora (ICN-MHN), Saúl Prada-Pedreros (MPUJ), Fernando Sarmiento Parra, and Julieth Stella Cárdenas Hincapié (MLS). A.L.-B. thanks James Maclaine (BMNH), Anja Palandačić (NMW), Ulrich Schliewen, Robin Böhmer, and Patricia Schulze (ZSM) for hospitality and assistance during visits to collections under their care, and Marcelo R. Britto (MNRJ) for technical and logistic support at MNRJ, where the manuscript was partially completed. Thanks to Omar Melo for help with the photographs of the holotype; Camila Castellanos, for the photo of R. daraha (Figure 6c); and Jorge García-Melo for taking photographs of live specimens in the field. Please visit the visual catalog of Colombian fish “https://cavfish.unibague.edu.co/”. Financial support was given by Pontificia Universidad Javeriana with the “Carta Encíclica Laudato Si” grant in the project entitled “Ictiología y Cultura: Aproximación biológica y cultural a los datos obtenidos en la expedición en las cachiveras del río Vaupés” (#20112). A.L.-B. was supported by a postdoctoral fellowship from FAPERJ Pós-Doutorado Nota 10 (05/2019 - E-
26/202.356/2019).
==========================
Oreonectes damingshanensis • A New Species of Stream Fish (Cypriniformes, Nemacheilidae) from Guangxi, Southwest China
Oreonectes damingshanensis Yu, Luo, Lan, Xiao & Zhou,
in Yu, Luo, Lan, Zhou, Deng, Xiao et Zhou. 2023.
Damingshan Mountains Loach | 大明山岭鳅 || DOI: 10.3897/zookeys.1180.104645
Abstract
In this work, a new species of the genus Oreonectes is described, named Oreonectes damingshanensis Yu, Luo, Lan, Xiao & Zhou, sp. nov., collected from the Damingshan Mountains of the Guangxi Zhuang Autonomous Region, China. Phylogenetic trees constructed based on the mitochondrial Cyt b showed that the new species represents an independent evolutionary lineage, with uncorrected genetic distances (p-distance) from congeners ranging from 6.1% to 8.9%. Morphologically, the new species can be distinguished from five other species of the genus by a combination of characters. The discovery of this new species raises the number of known species of Oreonectes from five to six. Our study suggests that O. platycephalus may be a complex containing multiple species and that previously recorded areas need to be further delimited and reevaluated.
Key words: Morphology, new species, Oreonectes platycephalus complex, phylogeny, taxonomy
Live paratype of Oreonectes damingshanensis sp. nov.
Oreonectes damingshanensis Yu, Luo, Lan, Xiao & Zhou, sp. nov.
Oreonectes platycephalus (Günther, 1868): Wang 2022 (Guangxi, China); Luo et al. 2023 (Damingshan Mountains, Shanglin County, Guangxi, China).
Diagnosis: Oreonectes damingshanensis sp. nov. is assigned to the genus Oreonectes based on molecular phylogenetic analyses and the following characteristics, which are diagnostic for this genus: (1) anterior and posterior nostrils narrowly separated; (2) lips smooth, with furrows; (3) barbel-like elongation of anterior nostrils longer than depth of nostril tube; and (4) caudal fin rounded, dorsal fin with 6 or 7 branched rays (Du et al. 2023).
Etymology: The species epithet damingshanensis refers to the type locality, located within the Damingshan Mountains, Guangxi, China. The suggested English name is the Damingshan Mountains loach, and the Chinese name is Dà Míng Shān Lıˇng Qiū (大明山岭鳅).
Jing Yu, Tao Luo, Chang-Ting Lan, Jia-Jun Zhou, Huai-Qing Deng, Ning Xiao and Jiang Zhou. 2023. Oreonectes damingshanensis (Cypriniformes, Nemacheilidae), A New Species of Stream Fish from Guangxi, Southwest China. ZooKeys. 1180: 81-104. DOI: 10.3897/zookeys.1180.104645
==========================
Oreonectes damingshanensis Yu, Luo, Lan, Xiao & Zhou,
in Yu, Luo, Lan, Zhou, Deng, Xiao et Zhou. 2023.
Damingshan Mountains Loach | 大明山岭鳅 || DOI: 10.3897/zookeys.1180.104645
Abstract
In this work, a new species of the genus Oreonectes is described, named Oreonectes damingshanensis Yu, Luo, Lan, Xiao & Zhou, sp. nov., collected from the Damingshan Mountains of the Guangxi Zhuang Autonomous Region, China. Phylogenetic trees constructed based on the mitochondrial Cyt b showed that the new species represents an independent evolutionary lineage, with uncorrected genetic distances (p-distance) from congeners ranging from 6.1% to 8.9%. Morphologically, the new species can be distinguished from five other species of the genus by a combination of characters. The discovery of this new species raises the number of known species of Oreonectes from five to six. Our study suggests that O. platycephalus may be a complex containing multiple species and that previously recorded areas need to be further delimited and reevaluated.
Key words: Morphology, new species, Oreonectes platycephalus complex, phylogeny, taxonomy
Live paratype of Oreonectes damingshanensis sp. nov.
Oreonectes damingshanensis Yu, Luo, Lan, Xiao & Zhou, sp. nov.
Oreonectes platycephalus (Günther, 1868): Wang 2022 (Guangxi, China); Luo et al. 2023 (Damingshan Mountains, Shanglin County, Guangxi, China).
Diagnosis: Oreonectes damingshanensis sp. nov. is assigned to the genus Oreonectes based on molecular phylogenetic analyses and the following characteristics, which are diagnostic for this genus: (1) anterior and posterior nostrils narrowly separated; (2) lips smooth, with furrows; (3) barbel-like elongation of anterior nostrils longer than depth of nostril tube; and (4) caudal fin rounded, dorsal fin with 6 or 7 branched rays (Du et al. 2023).
Etymology: The species epithet damingshanensis refers to the type locality, located within the Damingshan Mountains, Guangxi, China. The suggested English name is the Damingshan Mountains loach, and the Chinese name is Dà Míng Shān Lıˇng Qiū (大明山岭鳅).
Jing Yu, Tao Luo, Chang-Ting Lan, Jia-Jun Zhou, Huai-Qing Deng, Ning Xiao and Jiang Zhou. 2023. Oreonectes damingshanensis (Cypriniformes, Nemacheilidae), A New Species of Stream Fish from Guangxi, Southwest China. ZooKeys. 1180: 81-104. DOI: 10.3897/zookeys.1180.104645
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Paracheilinus amanda • Review of Australian Species of Paracheilinus Fourmanoir (Teleostei: Labridae), with Description of A New Species from the Great Barrier Reef and Coral Sea
(A1-A2) Paracheilinus amanda, new species;
(B) P. carpenteri, (C) P. flavianalis,
(D) P. mccoskeri, (E) P. rubricaudalis.
in Tea & Walsh. 2023.
DOI: 10.1643/i2023019
twitter.com/FishGuyKai
Photographs by H. H. Tan (A1); T. Yamazumi (A2); T. Cameron (B); V. Chalias (C); T. Kawamoto (D); and N. DeLoach (E).
Abstract
Australian species of the cirrhilabrin labrid genus Paracheilinus are reviewed. Four species of Paracheilinus are reported from Australian waters: P. amanda, new species, from Flora, Holmes, and Osprey Reefs, Coral Sea, off northeast Queensland, and Harrier Reef, Great Barrier Reef; P. filamentosus from Lizard Island, Great Barrier Reef; P. flavianalis from Evans and Flinders Shoals, Timor Sea, off northeast Darwin, Northern Territory, and Ashmore, Scott, Seringapatam, and Hibernia Reefs in the north-western shelf of Western Australia; and P. nursalim from Flinders Shoal, Timor Sea, off northern Darwin, Northern Territory. Paracheilinus amanda, new species, has previously been confused for P. rubricaudalis from Melanesia, but molecular analysis of mitochondrial COI recovers both species as reciprocally monophyletic lineages, differing from each other by 1–1.2% in genetic distance. They further differ in aspects of live coloration of terminal phase (TP) males. Both species are allopatric and do not overlap in distribution. The new species is described on the basis of six specimens: the holotype and two paratypes from Harrier Reef, Great Barrier Reef, one paratype from Flora Reef, Coral Sea, and from two paratypes collected off Hula in southern Papua New Guinea, along the north-western margin of the Coral Sea. The discovery of P. nursalim in Australia represents a new and significant range extension from previous locality records of West Papua and Ambon Bay. Paracheilinus is rediagnosed, and keys, diagnoses, photographs, and Australian distribution records are presented for all species herein.
Paracheilinus amanda, new species, aquarium specimen from Harrier Reef, the Great Barrier Reef. Specimen not retained. Photograph by K. Endoh.
A selection of Paracheilinus in life.
(A1) Paracheilinus amanda, new species, ZRC 64175, male paratype, 47.6 mm SL, off Hula, southern Papua New Guinea, Coral Sea; (A2) P. amanda, new species, underwater photograph from Osprey Reef, Coral Sea;
(B) P. carpenteri, underwater photograph from Mabini, Batangas, Philippines. Note the darkened posterior dorsal- and caudal-fin bases and the presence of a second stripe behind the pectoral fin; (C) P. flavianalis, underwater photograph from Bali, Indonesia;
(D) P. mccoskeri, underwater photograph from Khao Lak, Thailand; (E) P. rubricaudalis, underwater photograph from Mborokua, Solomon Islands. Note the reduced markings on caudal fin.
Photographs by H. H. Tan (A1); T. Yamazumi (A2); T. Cameron (B); V. Chalias (C); T. Kawamoto (D); and N. DeLoach (E).
Paracheilinus filamentosus, images of live and preserved specimens.
(A) Male in resting colors, underwater photograph from Guadalcanal, Solomon Islands; (B) flashing male in nuptial colors, underwater photograph from Nggatokae, western Solomon Islands; (C) flashing male in nuptial colors, underwater photograph from the Solomon Islands; (D) AMS I.17479-001, 51.7 mm SL, male paratype, Tassafaronga Point, Guadalcanal, Solomon Islands. Note purple spines and rays in preservation; (E) harem comprising one TP male (middle) and several females and immature males, underwater photograph from Lovukol, central Solomon Islands.
Photographs by M. Rosenstein (A–C, E) and Y. K. Tea (D).
Select individuals of Paracheilinus flavianalis demonstrating variability in the number of dorsal-fin filaments, coloration of anal fin, and spot band pattern on the anal fin.
(A) Underwater photograph from Triton Bay, Indonesia; (B) underwater photograph from Wakatobi, Sulawesi, Indonesia; (C–D) underwater photographs from Bali, Indonesia.
Photographs by R. Smith (A); J. Castellano (B); W. Osborn (C); and R. H. Kuiter (D).
Yi-Kai Tea and Fenton Walsh. 2023. Review of Australian Species of Paracheilinus Fourmanoir (Teleostei: Labridae), with Description of A New Species from the Great Barrier Reef and Coral Sea. Ichthyology & Herpetology. 111(3); 397-415. DOI: 10.1643/i2023019
twitter.com/FishGuyKai/status/1702273836182602205
twitter.com/IchsAndHerps/status/1702346910223204656
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(A1-A2) Paracheilinus amanda, new species;
(B) P. carpenteri, (C) P. flavianalis,
(D) P. mccoskeri, (E) P. rubricaudalis.
in Tea & Walsh. 2023.
DOI: 10.1643/i2023019
twitter.com/FishGuyKai
Photographs by H. H. Tan (A1); T. Yamazumi (A2); T. Cameron (B); V. Chalias (C); T. Kawamoto (D); and N. DeLoach (E).
Abstract
Australian species of the cirrhilabrin labrid genus Paracheilinus are reviewed. Four species of Paracheilinus are reported from Australian waters: P. amanda, new species, from Flora, Holmes, and Osprey Reefs, Coral Sea, off northeast Queensland, and Harrier Reef, Great Barrier Reef; P. filamentosus from Lizard Island, Great Barrier Reef; P. flavianalis from Evans and Flinders Shoals, Timor Sea, off northeast Darwin, Northern Territory, and Ashmore, Scott, Seringapatam, and Hibernia Reefs in the north-western shelf of Western Australia; and P. nursalim from Flinders Shoal, Timor Sea, off northern Darwin, Northern Territory. Paracheilinus amanda, new species, has previously been confused for P. rubricaudalis from Melanesia, but molecular analysis of mitochondrial COI recovers both species as reciprocally monophyletic lineages, differing from each other by 1–1.2% in genetic distance. They further differ in aspects of live coloration of terminal phase (TP) males. Both species are allopatric and do not overlap in distribution. The new species is described on the basis of six specimens: the holotype and two paratypes from Harrier Reef, Great Barrier Reef, one paratype from Flora Reef, Coral Sea, and from two paratypes collected off Hula in southern Papua New Guinea, along the north-western margin of the Coral Sea. The discovery of P. nursalim in Australia represents a new and significant range extension from previous locality records of West Papua and Ambon Bay. Paracheilinus is rediagnosed, and keys, diagnoses, photographs, and Australian distribution records are presented for all species herein.
Paracheilinus amanda, new species, aquarium specimen from Harrier Reef, the Great Barrier Reef. Specimen not retained. Photograph by K. Endoh.
A selection of Paracheilinus in life.
(A1) Paracheilinus amanda, new species, ZRC 64175, male paratype, 47.6 mm SL, off Hula, southern Papua New Guinea, Coral Sea; (A2) P. amanda, new species, underwater photograph from Osprey Reef, Coral Sea;
(B) P. carpenteri, underwater photograph from Mabini, Batangas, Philippines. Note the darkened posterior dorsal- and caudal-fin bases and the presence of a second stripe behind the pectoral fin; (C) P. flavianalis, underwater photograph from Bali, Indonesia;
(D) P. mccoskeri, underwater photograph from Khao Lak, Thailand; (E) P. rubricaudalis, underwater photograph from Mborokua, Solomon Islands. Note the reduced markings on caudal fin.
Photographs by H. H. Tan (A1); T. Yamazumi (A2); T. Cameron (B); V. Chalias (C); T. Kawamoto (D); and N. DeLoach (E).
Paracheilinus filamentosus, images of live and preserved specimens.
(A) Male in resting colors, underwater photograph from Guadalcanal, Solomon Islands; (B) flashing male in nuptial colors, underwater photograph from Nggatokae, western Solomon Islands; (C) flashing male in nuptial colors, underwater photograph from the Solomon Islands; (D) AMS I.17479-001, 51.7 mm SL, male paratype, Tassafaronga Point, Guadalcanal, Solomon Islands. Note purple spines and rays in preservation; (E) harem comprising one TP male (middle) and several females and immature males, underwater photograph from Lovukol, central Solomon Islands.
Photographs by M. Rosenstein (A–C, E) and Y. K. Tea (D).
Select individuals of Paracheilinus flavianalis demonstrating variability in the number of dorsal-fin filaments, coloration of anal fin, and spot band pattern on the anal fin.
(A) Underwater photograph from Triton Bay, Indonesia; (B) underwater photograph from Wakatobi, Sulawesi, Indonesia; (C–D) underwater photographs from Bali, Indonesia.
Photographs by R. Smith (A); J. Castellano (B); W. Osborn (C); and R. H. Kuiter (D).
Yi-Kai Tea and Fenton Walsh. 2023. Review of Australian Species of Paracheilinus Fourmanoir (Teleostei: Labridae), with Description of A New Species from the Great Barrier Reef and Coral Sea. Ichthyology & Herpetology. 111(3); 397-415. DOI: 10.1643/i2023019
twitter.com/FishGuyKai/status/1702273836182602205
twitter.com/IchsAndHerps/status/1702346910223204656
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Opistognathus ctenion • A New Jawfish (Perciformes: Opistognathidae) from southern Japan
Opistognathus ctenion
Fujiwara, Motomura & Shinohara, 2023
DOI: 10.3897/zookeys.1179.109813
Abstract
Opistognathus ctenion sp. nov. (Perciformes: Opistognathidae) is described on the basis of three specimens (17.3–30.6 mm in standard length) collected from the Osumi and Ryukyu islands, southern Japan in depths of 35–57 m. Although most similar to Opistognathus triops, recently described from Tonga and Vanuatu, the new species differs in mandibular pore arrangement, dorsal- and caudal-fin coloration, fewer gill rakers, and lacks blotches or stripes on the snout, suborbital region and both jaws.
Key words: Actinopterygii, dredge, new species, Osumi Islands, Ryukyu Islands, taxonomy
Opistognathus ctenion Fresh coloration of two paratypes
A, C KAUM–I. 174226, 30.6 mm SL; B, D KAUM–I. 174227, 26.2 mm SL
A, B lateral views; C, D dorsal views.
photographed by KAUM
Opistognathus ctenion sp. nov.
New English name: Japanese White spotted Jawfish
New standard Japanese name: Shiratama-agoamadai
Diagnosis: A species of Opistognathus distinguished from congeners by the following combination of characters: posterior end of upper jaw rigid, without flexible lamina; dorsal-fin rays XI, 16–18; anterior dorsal-fin spines very stout and straight, and their distal ends not transversely forked; anal-fin rays II, 17; gill rakers 6 or 7 + 13 or 14 = 20 or 21; vertebrae 10 + 22 = 32; longitudinal scale rows c. 40–50; lateral line terminating below 4th–6th soft ray of dorsal fin; 4th and 5th mandibular pore positions usually included 2 and 6–7 pores, respectively; body scales absent anterior to vertical below 4th or 5th dorsal-fin spine; vomerine teeth 2; body reddish-brown with 3 or 4 longitudinal rows of c. 8–10 whitish blotches; cheek and opercle with five or six whitish blotches; snout, suborbital region, and both jaws without blotches or stripes; spinous dorsal fin with ocellus between 2nd to 5th spines; dorsal-fin soft-rayed portion with two reddish-orange stripes; pectoral-fin base with one or two whitish blotches; caudal fin uniformly faint orange or reddish-yellow.
Etymology: The specific name is a noun in apposition derived from the Greek diminutive κτενίον, meaning “a small comb”. It refers to the low gill raker numbers in the new species, one of the lowest recorded for Indo-Pacific species of Opistognathus (see below).
Distributional records of Opistognathus ctenion.
Kyoji Fujiwara, Hiroyuki Motomura and Gento Shinohara. 2023. Opistognathus ctenion (Perciformes, Opistognathidae): A New Jawfish from southern Japan. ZooKeys. 1179: 353-364. DOI: 10.3897/zookeys.1179.109813
==========================
Opistognathus ctenion
Fujiwara, Motomura & Shinohara, 2023
DOI: 10.3897/zookeys.1179.109813
Abstract
Opistognathus ctenion sp. nov. (Perciformes: Opistognathidae) is described on the basis of three specimens (17.3–30.6 mm in standard length) collected from the Osumi and Ryukyu islands, southern Japan in depths of 35–57 m. Although most similar to Opistognathus triops, recently described from Tonga and Vanuatu, the new species differs in mandibular pore arrangement, dorsal- and caudal-fin coloration, fewer gill rakers, and lacks blotches or stripes on the snout, suborbital region and both jaws.
Key words: Actinopterygii, dredge, new species, Osumi Islands, Ryukyu Islands, taxonomy
Opistognathus ctenion Fresh coloration of two paratypes
A, C KAUM–I. 174226, 30.6 mm SL; B, D KAUM–I. 174227, 26.2 mm SL
A, B lateral views; C, D dorsal views.
photographed by KAUM
Opistognathus ctenion sp. nov.
New English name: Japanese White spotted Jawfish
New standard Japanese name: Shiratama-agoamadai
Diagnosis: A species of Opistognathus distinguished from congeners by the following combination of characters: posterior end of upper jaw rigid, without flexible lamina; dorsal-fin rays XI, 16–18; anterior dorsal-fin spines very stout and straight, and their distal ends not transversely forked; anal-fin rays II, 17; gill rakers 6 or 7 + 13 or 14 = 20 or 21; vertebrae 10 + 22 = 32; longitudinal scale rows c. 40–50; lateral line terminating below 4th–6th soft ray of dorsal fin; 4th and 5th mandibular pore positions usually included 2 and 6–7 pores, respectively; body scales absent anterior to vertical below 4th or 5th dorsal-fin spine; vomerine teeth 2; body reddish-brown with 3 or 4 longitudinal rows of c. 8–10 whitish blotches; cheek and opercle with five or six whitish blotches; snout, suborbital region, and both jaws without blotches or stripes; spinous dorsal fin with ocellus between 2nd to 5th spines; dorsal-fin soft-rayed portion with two reddish-orange stripes; pectoral-fin base with one or two whitish blotches; caudal fin uniformly faint orange or reddish-yellow.
Etymology: The specific name is a noun in apposition derived from the Greek diminutive κτενίον, meaning “a small comb”. It refers to the low gill raker numbers in the new species, one of the lowest recorded for Indo-Pacific species of Opistognathus (see below).
Distributional records of Opistognathus ctenion.
Kyoji Fujiwara, Hiroyuki Motomura and Gento Shinohara. 2023. Opistognathus ctenion (Perciformes, Opistognathidae): A New Jawfish from southern Japan. ZooKeys. 1179: 353-364. DOI: 10.3897/zookeys.1179.109813
==========================
Generic reassignment of Centropristis fuscula Poey, 1861 (Teleostei: Serranidae), with re-description of the species and comments on its geographical range and sexual system
full papaer at:- www.mapress.com/zt/article/view/zootaxa.5346.1.3
==========================
- ALFREDO CARVALHO-FILHO+
- CAROLE C. BALDWIN+
- LUCIANO G. FISCHER+
- D. ROSS ROBERTSON+
- ATHILA BERTONCINI+
- LUCAS CANES GARCIA+
- JODIR PEREIRA DA SILVA+
- CLAUDIO L. S. SAMPAIO+
full papaer at:- www.mapress.com/zt/article/view/zootaxa.5346.1.3
==========================
New species of Farlowella (Siluriformes: Loricariidae) from the rio Tapajós basin, Pará, BrazilManuela Dopazo1 , Wolmar B. Wosiacki2 and Marcelo R. Britto1
PDF: EN XML: EN | Cite this article
Abstract
A new species of stick-catfish Farlowella is described from streams of the lower rio Tapajós drainage, in Pará State, northern Brazil. The new species is distinguished from all congeners by a naked gular region (vs. gular region with plates) and from most congeners by the presence of five lateral series of plate rows on anterior region of body (vs. four). The new species shows variation in the series of abdominal plates and a discussion on the variation of abdominal plates within Farlowella is made and comments on synapomorphic characters in Farlowellini.
Keywords: Amazon, Armored catfish, Biodiversity,Loricariinae,Taxonomy.
Introduction
The genus Farlowella Eigenmann & Eigenmann, 1889 is a component of the freshwater fish fauna of the Neotropics. With 32 valid species, Farlowella is the second-most species-rich genus of Loricariinae, a sub-family comprised of 262 valid species in 31 genera (Delgadillo et al., 2021; Londoño-Burbano, Reis, 2021; Fricke et al., 2023). Farlowella representatives are widely distributed in the main cis-Andean South America river drainages and trans-Andean Maracaibo and Magdalena river basins (Terán et al., 2019). They are easily distinguished by having a pronounced rostrum, a thin, elongated, brown body with two longitudinal bands that extend from the tip of the rostrum to the caudal peduncle (Covain, Fisch-Muller, 2007), resembling dry twigs or sticks, which justifies the popular name stick catfishes.
The first taxonomic study was the description of the genus Acestra by Kner (1853), with the first species described: Acestra acus and A. oxyrryncha, but without designating the type species of the genus, until A. acus was determined by Bleeker (1862). However, Acestra was already occupied in Hemiptera (Dallas, 1852) and the name Farlowella was then replaced by Eigenmann, Eigenmann (1889). From the end of the 19th century, several species were described, totaling 37 names that remained for almost a century, when Retzer, Page (1996) revised the genus based on characters of external morphology. This was the last revision of its species, as well as the first exclusive hypothesis of the phylogenetic relationships of the genus. In that study, the authors performed a phylogenetic analysis with morphological data including only one external group, Aposturisoma myriodon Isbrücker, Britski, Nijssen & Ortega, 1983 (= Farlowella myriodon), that was used to root the tree; the monophyly of the genus, and species relationships were not actually tested. The authors also proposed six species groups and six species were considered as incertae sedis.
Recently, Londoño-Burbano, Reis (2021), based on combined molecular and morphological phylogenetic analysis, formally recognized Aposturisoma myriodon as a member of Farlowella to assign the monophyly of the genus. Although A. myriodon is phenotypically different from Farlowella, this configuration had already been recovered by Covain et al. (2016). Based on the review of Farlowella material deposited in different collections and on the examination of material collected in the river near the confluence with rio Tapajós, in its lower portion, we identified a new species of Farlowella, which is described herein.
Full paper @ ni.bio.br/v21n1/
==========================
PDF: EN XML: EN | Cite this article
Abstract
A new species of stick-catfish Farlowella is described from streams of the lower rio Tapajós drainage, in Pará State, northern Brazil. The new species is distinguished from all congeners by a naked gular region (vs. gular region with plates) and from most congeners by the presence of five lateral series of plate rows on anterior region of body (vs. four). The new species shows variation in the series of abdominal plates and a discussion on the variation of abdominal plates within Farlowella is made and comments on synapomorphic characters in Farlowellini.
Keywords: Amazon, Armored catfish, Biodiversity,Loricariinae,Taxonomy.
Introduction
The genus Farlowella Eigenmann & Eigenmann, 1889 is a component of the freshwater fish fauna of the Neotropics. With 32 valid species, Farlowella is the second-most species-rich genus of Loricariinae, a sub-family comprised of 262 valid species in 31 genera (Delgadillo et al., 2021; Londoño-Burbano, Reis, 2021; Fricke et al., 2023). Farlowella representatives are widely distributed in the main cis-Andean South America river drainages and trans-Andean Maracaibo and Magdalena river basins (Terán et al., 2019). They are easily distinguished by having a pronounced rostrum, a thin, elongated, brown body with two longitudinal bands that extend from the tip of the rostrum to the caudal peduncle (Covain, Fisch-Muller, 2007), resembling dry twigs or sticks, which justifies the popular name stick catfishes.
The first taxonomic study was the description of the genus Acestra by Kner (1853), with the first species described: Acestra acus and A. oxyrryncha, but without designating the type species of the genus, until A. acus was determined by Bleeker (1862). However, Acestra was already occupied in Hemiptera (Dallas, 1852) and the name Farlowella was then replaced by Eigenmann, Eigenmann (1889). From the end of the 19th century, several species were described, totaling 37 names that remained for almost a century, when Retzer, Page (1996) revised the genus based on characters of external morphology. This was the last revision of its species, as well as the first exclusive hypothesis of the phylogenetic relationships of the genus. In that study, the authors performed a phylogenetic analysis with morphological data including only one external group, Aposturisoma myriodon Isbrücker, Britski, Nijssen & Ortega, 1983 (= Farlowella myriodon), that was used to root the tree; the monophyly of the genus, and species relationships were not actually tested. The authors also proposed six species groups and six species were considered as incertae sedis.
Recently, Londoño-Burbano, Reis (2021), based on combined molecular and morphological phylogenetic analysis, formally recognized Aposturisoma myriodon as a member of Farlowella to assign the monophyly of the genus. Although A. myriodon is phenotypically different from Farlowella, this configuration had already been recovered by Covain et al. (2016). Based on the review of Farlowella material deposited in different collections and on the examination of material collected in the river near the confluence with rio Tapajós, in its lower portion, we identified a new species of Farlowella, which is described herein.
Full paper @ ni.bio.br/v21n1/
==========================
Iniistius bakunawa • A New Species of Razor Wrasse (Teleostei: Labridae) from the Philippines and Western Australia
Iniistius bakunawa
Sorgon, Tea, Meren & Nañola, 2023
RAFFLES BULLETIN OF ZOOLOGY. 71
Eclipse-spot Razor Wrasse || twitter.com/FishGuyKai
Abstract.
Iniistius bakunawa, new species, is described on the basis of nine specimens consisting of the holotype and six paratypes collected from fish markets in the islands of Panay, Cebu, Bohol, and Jolo in the Philippines, and two paratypes from the Dampier Archipelago, Western Australia. The new species is distinctive in having a pale yellowish to jade green body with a large concentric black and white ellipsoid ocellus on the posteriormost edge of its dorsal fin. Aside from live colouration details, the new species is readily diagnosed from congeners in having the following combination of characters: 7 horizontal rows of scales on cheek; gill rakers 4–6 + 8–11 = 12–17; gill rakers short, bearing teeth; and tubed lateral line scales 23–26. Assignment of the new species to the genus Iniistius is accompanied with a brief discussion of the currently inadequate diagnosis of the genus from Xyrichtys.
Key words. coral reefs, fish markets, Labridae, Novaculini, taxonomy, systematics
Iniistius bakunawa, new species, KAUM-I. 80684, paratype, 172.0 mm SL, Panay Island, Philippines. Freshly dead specimen showing colouration in life
Photograph by H. Motomura
Iniistius bakunawa, new species, A–C, freshly dead specimens showing colouration in life; and D–F, X-rays.
A, USNM 435404, paratype, 162.4 mm SL, Cebu Island, Philippines; B, USNM 437745, paratype, 155.1 mm SL, Panay Island, Philippines; C, USNM 437747, paratype, 158.8 mm SL, Panay Island, Philippines;
D, CSIRO H 1488-1, paratype, 129.8 mm SL, off northwest Dampier Archipelago, Western Australia; E, CSIRO H 1506-1, paratype, 144.5 mm SL, off northern Dampier Archipelago, Western Australia; F, KAUM-I. 80684, paratype, 172.0 mm SL, Panay Island, Philippines.
Photographs by J.T. Williams. X-rays provided by K. Parkinson.
Iniistius bakunawa, new species
Eclipse-spot Razor Wrasse
Iniistius sp. (Fukui, 2017): 184 (colour photograph of specimen from Panay Island, Philippines [reproduced here in Fig. 1A; KAUM-I. 80684]).
Diagnosis. A species of Iniistius distinct from all congeners based on the following combination of characters and live colouration details: 7 horizontal rows of scales on cheek; gill rakers 4–6 + 8–11 = 12–17; gill rakers short, bearing teeth; pored lateral line scales 19–20 + 4–6 = 23–26; 2 scales dorsoanteriorly on opercle; body yellowish to jade green; posteriormost dorsal fin with a large black centred white ellipsoid ocellus.
Etymology. The specific epithet is given after Bakunawa, a serpentine or draconic figure in Visayan mythology believed to be responsible for causing an eclipse by devouring the moon. The common name is given after the black centred white ellipsoidal ocellus on the posterior dorsal fin. The name bakunawa is treated as a noun in apposition.
Species of Iniistius are known by a variety of common names, including razor wrasse, cleaver wrasse, and razorfish. The first two names are sometimes used for other novaculin species in the genera Novaculops and Xyrichtys, whereas razorfish is sometimes used for Centriscus and Aeoliscus (Sygnathiformes; Centriscidae; also known as shrimpfish). To maintain consistent terminology with other members of the Novaculini and to avoid confusion with the Centriscidae, we recommend razor wrasse as the preferred common name when referring to species in the genus Iniistius.
Kent Elson S. Sorgon, Yi-Kai Tea, Jasmin C. Meren and Cleto L. Nañola Jr. 2023. Iniistius bakunawa, A New Species of Razor Wrasse (Teleostei: Labridae) from the Philippines and Western Australia. RAFFLES BULLETIN OF ZOOLOGY. 71; 511–519.
twitter.com/FishGuyKai/status/1698616150752727488
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Iniistius bakunawa
Sorgon, Tea, Meren & Nañola, 2023
RAFFLES BULLETIN OF ZOOLOGY. 71
Eclipse-spot Razor Wrasse || twitter.com/FishGuyKai
Abstract.
Iniistius bakunawa, new species, is described on the basis of nine specimens consisting of the holotype and six paratypes collected from fish markets in the islands of Panay, Cebu, Bohol, and Jolo in the Philippines, and two paratypes from the Dampier Archipelago, Western Australia. The new species is distinctive in having a pale yellowish to jade green body with a large concentric black and white ellipsoid ocellus on the posteriormost edge of its dorsal fin. Aside from live colouration details, the new species is readily diagnosed from congeners in having the following combination of characters: 7 horizontal rows of scales on cheek; gill rakers 4–6 + 8–11 = 12–17; gill rakers short, bearing teeth; and tubed lateral line scales 23–26. Assignment of the new species to the genus Iniistius is accompanied with a brief discussion of the currently inadequate diagnosis of the genus from Xyrichtys.
Key words. coral reefs, fish markets, Labridae, Novaculini, taxonomy, systematics
Iniistius bakunawa, new species, KAUM-I. 80684, paratype, 172.0 mm SL, Panay Island, Philippines. Freshly dead specimen showing colouration in life
Photograph by H. Motomura
Iniistius bakunawa, new species, A–C, freshly dead specimens showing colouration in life; and D–F, X-rays.
A, USNM 435404, paratype, 162.4 mm SL, Cebu Island, Philippines; B, USNM 437745, paratype, 155.1 mm SL, Panay Island, Philippines; C, USNM 437747, paratype, 158.8 mm SL, Panay Island, Philippines;
D, CSIRO H 1488-1, paratype, 129.8 mm SL, off northwest Dampier Archipelago, Western Australia; E, CSIRO H 1506-1, paratype, 144.5 mm SL, off northern Dampier Archipelago, Western Australia; F, KAUM-I. 80684, paratype, 172.0 mm SL, Panay Island, Philippines.
Photographs by J.T. Williams. X-rays provided by K. Parkinson.
Iniistius bakunawa, new species
Eclipse-spot Razor Wrasse
Iniistius sp. (Fukui, 2017): 184 (colour photograph of specimen from Panay Island, Philippines [reproduced here in Fig. 1A; KAUM-I. 80684]).
Diagnosis. A species of Iniistius distinct from all congeners based on the following combination of characters and live colouration details: 7 horizontal rows of scales on cheek; gill rakers 4–6 + 8–11 = 12–17; gill rakers short, bearing teeth; pored lateral line scales 19–20 + 4–6 = 23–26; 2 scales dorsoanteriorly on opercle; body yellowish to jade green; posteriormost dorsal fin with a large black centred white ellipsoid ocellus.
Etymology. The specific epithet is given after Bakunawa, a serpentine or draconic figure in Visayan mythology believed to be responsible for causing an eclipse by devouring the moon. The common name is given after the black centred white ellipsoidal ocellus on the posterior dorsal fin. The name bakunawa is treated as a noun in apposition.
Species of Iniistius are known by a variety of common names, including razor wrasse, cleaver wrasse, and razorfish. The first two names are sometimes used for other novaculin species in the genera Novaculops and Xyrichtys, whereas razorfish is sometimes used for Centriscus and Aeoliscus (Sygnathiformes; Centriscidae; also known as shrimpfish). To maintain consistent terminology with other members of the Novaculini and to avoid confusion with the Centriscidae, we recommend razor wrasse as the preferred common name when referring to species in the genus Iniistius.
Kent Elson S. Sorgon, Yi-Kai Tea, Jasmin C. Meren and Cleto L. Nañola Jr. 2023. Iniistius bakunawa, A New Species of Razor Wrasse (Teleostei: Labridae) from the Philippines and Western Australia. RAFFLES BULLETIN OF ZOOLOGY. 71; 511–519.
twitter.com/FishGuyKai/status/1698616150752727488
==========================
Callogobius williamsi, a new species of goby (Teleostei: Gobiidae) from the Marquesas Islands, with notes on the status of all nominal Callogobius speciesPISCESGOBIIFORMESFRENCH POLYNESIATYPE SPECIMENSTAXONOMYSYSTEMATICSAbstractCallogobius williamsi new species is described from the 32.9 mm SL holotype and 29 paratypes (6.9–32.5 mm SL) from the Marquesas Islands, South Pacific Ocean. Callogobius williamsi is distinguished from all other known Callogobius species by the following combination of characters: scales mostly cycloid, ctenoid scales, if present, restricted to the mid-lateral caudal peduncle, 23–26 (mode 25) scales in lateral series, preopercular papillae row (Row 20) absent, and the interorbital canal with pores B′, D, and F′ present. Callogobius williamsi belongs to a group of 23 nominal species (the hasseltii group) that are hypothesized to be monophyletic based on the shared presence of narrow and closely spaced dorsal processes of the cleithrum and an elongate caudal fin (greater than head length in specimens over 20 mm SL). Following the species description is a discussion of the status of all nominal species of Callogobius including a table that provides provisional status for all species correctly assigned to the genus.
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Betta andrei • A New Species of Black Water Fighting Fish (Teleostei: Osphronemidae) from Singkep Island, Riau Islands, Indonesia
Betta andrei
Tan, 2023
a, B. waseri, d, B. spilotogena and j, B. andrei.
RAFFLES BULLETIN OF ZOOLOGY. 71
Abstract
A new species of Betta from the B. waseri group is described based on a single specimen from Singkep Island. It appears to be closely allied to B. spilotogena. Betta andrei, new species, differs from B. spilotogena in having a different throat pattern, comprised of a black lower jaw, continuous with a large pitcher-like pattern on throat, ending with a protruding segment on buccal membrane (vs. isolated teardrop shaped black mark on throat); opercle uniform brown with dark brown spots along posterior margin; faint black transverse bars on the dorsal- and caudal-fin interradial membranes; absence of a dark distal border on anal fin.
Keywords. Betta, new species, Indonesia, peat swamp, biodiversity
Betta andrei, ZRC 64279, 50.7 mm SL:
topmost – live fish; second from top – freshly preserved fish with white background; third from top – freshly preserved fish with black background; bottom – radiograph.
Composite of head region of Betta andrei (ZRC 64279, 50.7 mm SL),
showing oblique (top) and ventral (bottom) views.
Betta andrei, new species
Diagnosis. Betta andrei can be distinguished from other members of the B. waseri group in having the following combination of characters: black lower jaw, continuous with large black pitcher-shaped mark on throat, ending with a protrusion on buccal membrane (see Figs. 2–3); opercle uniform brown with dark brown mottling along posterior margin, operculum without lower distal margin black; faint black transverse bars on the dorsal and caudal fin interradial membranes; absence of a dark distal border on anal fin.
Etymology. This species is named for Andre Chandra, an intrepid fish collector and enthusiast, who rendered much assistance to the author in procuring specimens and information; fishy discussions and good meals. A noun in the genitive.
Stream in which the holotype of Betta andrei was collected (Photograph: Andre Chandra).
Schematic diagrams of throat pattern of the Betta waseri group in chronological order of discovery: a, B. waseri, b, B. hipposideros, c, B. tomi, d, B. spilotogena, e, B. chloropharynx, f, B. renata, g, B. pi, h, B. pardalotos, i, B. omega, and j, Betta andrei.
Tan Heok Hui. 2023. A New Species of Black Water Fighting Fish from Singkep Island (Teleostei: Osphronemidae). RAFFLES BULLETIN OF ZOOLOGY. 71: 491–495.
==========================
Betta andrei
Tan, 2023
a, B. waseri, d, B. spilotogena and j, B. andrei.
RAFFLES BULLETIN OF ZOOLOGY. 71
Abstract
A new species of Betta from the B. waseri group is described based on a single specimen from Singkep Island. It appears to be closely allied to B. spilotogena. Betta andrei, new species, differs from B. spilotogena in having a different throat pattern, comprised of a black lower jaw, continuous with a large pitcher-like pattern on throat, ending with a protruding segment on buccal membrane (vs. isolated teardrop shaped black mark on throat); opercle uniform brown with dark brown spots along posterior margin; faint black transverse bars on the dorsal- and caudal-fin interradial membranes; absence of a dark distal border on anal fin.
Keywords. Betta, new species, Indonesia, peat swamp, biodiversity
Betta andrei, ZRC 64279, 50.7 mm SL:
topmost – live fish; second from top – freshly preserved fish with white background; third from top – freshly preserved fish with black background; bottom – radiograph.
Composite of head region of Betta andrei (ZRC 64279, 50.7 mm SL),
showing oblique (top) and ventral (bottom) views.
Betta andrei, new species
Diagnosis. Betta andrei can be distinguished from other members of the B. waseri group in having the following combination of characters: black lower jaw, continuous with large black pitcher-shaped mark on throat, ending with a protrusion on buccal membrane (see Figs. 2–3); opercle uniform brown with dark brown mottling along posterior margin, operculum without lower distal margin black; faint black transverse bars on the dorsal and caudal fin interradial membranes; absence of a dark distal border on anal fin.
Etymology. This species is named for Andre Chandra, an intrepid fish collector and enthusiast, who rendered much assistance to the author in procuring specimens and information; fishy discussions and good meals. A noun in the genitive.
Stream in which the holotype of Betta andrei was collected (Photograph: Andre Chandra).
Schematic diagrams of throat pattern of the Betta waseri group in chronological order of discovery: a, B. waseri, b, B. hipposideros, c, B. tomi, d, B. spilotogena, e, B. chloropharynx, f, B. renata, g, B. pi, h, B. pardalotos, i, B. omega, and j, Betta andrei.
Tan Heok Hui. 2023. A New Species of Black Water Fighting Fish from Singkep Island (Teleostei: Osphronemidae). RAFFLES BULLETIN OF ZOOLOGY. 71: 491–495.
==========================
Rhyacoglanis beninei • Description and Phylogenetic Position of A New Species of Rhyacoglanis (Siluriformes: Pseudopimelodidae) from the Jamanxim River Basin
Rhyacoglanis beninei
Crispim-Rodrigues, Silva, Shibatta, Kuranaka & Oliveira, 2023
DOI: 10.1590/1982-0224-2023-0051
Abstract
In this study, a new species of Rhyacoglanis is described from the Jamanxim River basin, Tapajós River basin. The new species differs from congeners based on the combination of the following diagnostic characters: two oblique dark bands formed by an agglomerate of melanophores on the predorsal region; dorsal confluence between the dark subdorsal and subadipose bands in large juveniles and adults; ventral confluence between the dark subadipose and caudal peduncle bands; body without conspicuous dark brown spots; complete dark band on caudal peduncle; body with three dark bands; a thin dark caudal-fin band; pectoral-fin spine with anterior serrae distributed along the entire margin; the posterior tip of the post-cleithral process reaching vertical through the base of the dorsal-fin spine; and hypural 5 free of hypural 3 and 4 and pointed caudal-fin lobes. Additionally, our molecular phylogenetic results using ultraconserved elements (UCEs) corroborate the new species as Rhyacoglanis and sister to an undescribed species of Rhyacoglanis from the Xingu River basin. Moreover, as pointed out in previous studies, we confirm Cruciglanis as a sister group to Pseudopimelodus plus Rhyacoglanis.
Keywords: Amazon basin; Bumblebee catfishes; Phylogenomic; South America region; Pseudopimelodinae
Rhyacoglanis beninei, holotype, MZUSP 127014, 59.1 mm SL, from córrego Jussara, an affluent of Jamanxim River, Tapajós River basin. Scale bar = 10 mm.
A. Habitat of Rhyacoglanis beninei in córrego Jussara;
B. A rock where specimens of R. beninei were associated;
C. Paratype of R. beninei just after capture.
Photos: Gabriel S. Costa e Silva.
Rhyacoglanis beninei, new species
Diagnosis. Rhyacoglanis beninei can be diagnosed from all congeners by two oblique dorsal dark brown bars on the predorsal region (Fig. 2) (vs. absent). Additionally, R. beninei is distinguished from some congeners by having a dorsal confluence between the dark subdorsal and subadipose bands in large juveniles and adults (> 28 mm SL) (vs. lack dorsal confluence in R. paranensis, R. annulatus, R. varii, and R. rapppydanielae); ventral confluence between the dark subadipose and caudal peduncle bands (vs. lack ventral confluence in R. annulatus, R. epiblepsis, R. paranensis, R. seminiger, and R. rapppydanielae); body without conspicuous dark brown spots (vs. conspicuous dark brown spots in R. epiblepsis and R. rapppydanielae); complete dark band on caudal peduncle (vs. caudal peduncle-band with a unpigmented central region in R. annulatus); body with three dark bands (vs. two dark bands in R. seminiger); a thin dark caudal-fin bands (vs. large caudal-fin bands in R. paranensis and R. epiblepsis); pectoral-fin spine with anterior serrae distributed along the entire margin (restricted to the proximal half in R. pulcher and R. seminiger); posterior tip of the post-cleithral process reaching vertical through the base of the dorsal-fin spine (vs. not reaching in R. epiblepsis and R. rapppydanielae); hypural 5 free of hypural 3 and 4 (vs. hypurals 4 and 5 fused in R. rapppydanielae); pointed caudal-fin lobes (vs. rounded lobes in R. epiblepsis).
Etymology. Rhyacoglanis beninei is named in honor of Ricardo Cardoso Benine, Professor at Universidade Estadual Paulista “Júlio de Mesquita Filho”, in recognition of his dedication and remarkable contributions to the knowledge of Neotropical freshwater fishes.
Pigmentation of oblique dark bars in the predorsal region of Rhyacoglanis beninei.
A. MZUEL 23049, 29.6 mm SL; B. LBP 32145, 32.9 mm SL; C. LBP 32145, 37.3 mm SL; D. MZUEL 23049, 42.6 mm SL; E. LBP 32145, 50.2 mm SL. Scale bars = 10 mm.
Variation pattern of dark body bands in Rhyacoglanis beninei.
A. MZUEL 23049, 42.6 mm SL; B. LBP 32145, 29.8 mm SL; C. LBP 32163, 27.0 mm SL; D. LBP 32163, 42.9 mm SL. Scale bars = 10 mm.
Jefferson Luan Crispim-Rodrigues, Gabriel de Souza da Costa e Silva, Oscar Akio Shibatta, Mariana Kuranaka and Claudio Oliveira. 2023. Description and Phylogenetic Position of A New Species of Rhyacoglanis (Siluriformes: Pseudopimelodidae) from the Jamanxim River Basin. Neotrop. ichthyol. 21(3); DOI: 10.1590/1982-0224-2023-0051
========================================
Rhyacoglanis beninei
Crispim-Rodrigues, Silva, Shibatta, Kuranaka & Oliveira, 2023
DOI: 10.1590/1982-0224-2023-0051
Abstract
In this study, a new species of Rhyacoglanis is described from the Jamanxim River basin, Tapajós River basin. The new species differs from congeners based on the combination of the following diagnostic characters: two oblique dark bands formed by an agglomerate of melanophores on the predorsal region; dorsal confluence between the dark subdorsal and subadipose bands in large juveniles and adults; ventral confluence between the dark subadipose and caudal peduncle bands; body without conspicuous dark brown spots; complete dark band on caudal peduncle; body with three dark bands; a thin dark caudal-fin band; pectoral-fin spine with anterior serrae distributed along the entire margin; the posterior tip of the post-cleithral process reaching vertical through the base of the dorsal-fin spine; and hypural 5 free of hypural 3 and 4 and pointed caudal-fin lobes. Additionally, our molecular phylogenetic results using ultraconserved elements (UCEs) corroborate the new species as Rhyacoglanis and sister to an undescribed species of Rhyacoglanis from the Xingu River basin. Moreover, as pointed out in previous studies, we confirm Cruciglanis as a sister group to Pseudopimelodus plus Rhyacoglanis.
Keywords: Amazon basin; Bumblebee catfishes; Phylogenomic; South America region; Pseudopimelodinae
Rhyacoglanis beninei, holotype, MZUSP 127014, 59.1 mm SL, from córrego Jussara, an affluent of Jamanxim River, Tapajós River basin. Scale bar = 10 mm.
A. Habitat of Rhyacoglanis beninei in córrego Jussara;
B. A rock where specimens of R. beninei were associated;
C. Paratype of R. beninei just after capture.
Photos: Gabriel S. Costa e Silva.
Rhyacoglanis beninei, new species
Diagnosis. Rhyacoglanis beninei can be diagnosed from all congeners by two oblique dorsal dark brown bars on the predorsal region (Fig. 2) (vs. absent). Additionally, R. beninei is distinguished from some congeners by having a dorsal confluence between the dark subdorsal and subadipose bands in large juveniles and adults (> 28 mm SL) (vs. lack dorsal confluence in R. paranensis, R. annulatus, R. varii, and R. rapppydanielae); ventral confluence between the dark subadipose and caudal peduncle bands (vs. lack ventral confluence in R. annulatus, R. epiblepsis, R. paranensis, R. seminiger, and R. rapppydanielae); body without conspicuous dark brown spots (vs. conspicuous dark brown spots in R. epiblepsis and R. rapppydanielae); complete dark band on caudal peduncle (vs. caudal peduncle-band with a unpigmented central region in R. annulatus); body with three dark bands (vs. two dark bands in R. seminiger); a thin dark caudal-fin bands (vs. large caudal-fin bands in R. paranensis and R. epiblepsis); pectoral-fin spine with anterior serrae distributed along the entire margin (restricted to the proximal half in R. pulcher and R. seminiger); posterior tip of the post-cleithral process reaching vertical through the base of the dorsal-fin spine (vs. not reaching in R. epiblepsis and R. rapppydanielae); hypural 5 free of hypural 3 and 4 (vs. hypurals 4 and 5 fused in R. rapppydanielae); pointed caudal-fin lobes (vs. rounded lobes in R. epiblepsis).
Etymology. Rhyacoglanis beninei is named in honor of Ricardo Cardoso Benine, Professor at Universidade Estadual Paulista “Júlio de Mesquita Filho”, in recognition of his dedication and remarkable contributions to the knowledge of Neotropical freshwater fishes.
Pigmentation of oblique dark bars in the predorsal region of Rhyacoglanis beninei.
A. MZUEL 23049, 29.6 mm SL; B. LBP 32145, 32.9 mm SL; C. LBP 32145, 37.3 mm SL; D. MZUEL 23049, 42.6 mm SL; E. LBP 32145, 50.2 mm SL. Scale bars = 10 mm.
Variation pattern of dark body bands in Rhyacoglanis beninei.
A. MZUEL 23049, 42.6 mm SL; B. LBP 32145, 29.8 mm SL; C. LBP 32163, 27.0 mm SL; D. LBP 32163, 42.9 mm SL. Scale bars = 10 mm.
Jefferson Luan Crispim-Rodrigues, Gabriel de Souza da Costa e Silva, Oscar Akio Shibatta, Mariana Kuranaka and Claudio Oliveira. 2023. Description and Phylogenetic Position of A New Species of Rhyacoglanis (Siluriformes: Pseudopimelodidae) from the Jamanxim River Basin. Neotrop. ichthyol. 21(3); DOI: 10.1590/1982-0224-2023-0051
========================================
Trophic ecology of the African riverine elephant fishes (Mormyridae)Gina Maria Sommer, Samuel Didier Njom, Adrian Indermaur, Arnold Roger Bitja Nyom, Petra Horká, Jaroslav Kukla, Zuzana Musilova
doi: https://doi.org/10.1101/2023.06.07.543841
This article is a preprint and has not been certified by peer review [what does this mean?].
00000030AbstractMultiple species of the elephant fishes (Mormyridae) commonly coexist in sympatry in most African tropical rivers and lakes. In this study, we investigated the trophic ecology and potential trophic niche partitioning of eleven mormyrid fish species from the Sanaga River system (Cameroon) using the stable isotopes of carbon and nitrogen of muscles and of trophic prey samples. Albeit mormyrids mainly feed on invertebrates, we found differences in isotope signals and the trophic niche partitioning in the studied species. We further show that species with elongated snout tend to show higher carbon and nitrogen isotope signals, suggesting a potential role of snout shape in their trophic preferences. Furthermore, we found significant differences in isotopic signatures within the Mormyrus genus, highlighting ecological niche diversification among three closely related species. We also report on different isotopic signals between seasons of the year in four species, possibly caused by species migration and/or anthropogenic agricultural activities. Overall, our research presents robust evidence of the trophic niche partitioning within the entire mormyrid species community, shedding light on the enigmatic evolutionary history of these fascinating African fishes.
Competing Interest StatementThe authors have declared no competing interest.
Copyright
The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC 4.0 International license.
==========================
doi: https://doi.org/10.1101/2023.06.07.543841
This article is a preprint and has not been certified by peer review [what does this mean?].
00000030AbstractMultiple species of the elephant fishes (Mormyridae) commonly coexist in sympatry in most African tropical rivers and lakes. In this study, we investigated the trophic ecology and potential trophic niche partitioning of eleven mormyrid fish species from the Sanaga River system (Cameroon) using the stable isotopes of carbon and nitrogen of muscles and of trophic prey samples. Albeit mormyrids mainly feed on invertebrates, we found differences in isotope signals and the trophic niche partitioning in the studied species. We further show that species with elongated snout tend to show higher carbon and nitrogen isotope signals, suggesting a potential role of snout shape in their trophic preferences. Furthermore, we found significant differences in isotopic signatures within the Mormyrus genus, highlighting ecological niche diversification among three closely related species. We also report on different isotopic signals between seasons of the year in four species, possibly caused by species migration and/or anthropogenic agricultural activities. Overall, our research presents robust evidence of the trophic niche partitioning within the entire mormyrid species community, shedding light on the enigmatic evolutionary history of these fascinating African fishes.
Competing Interest StatementThe authors have declared no competing interest.
Copyright
The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC 4.0 International license.
==========================
Moenkhausia guaruba • A New Species of Moenkhausia (Characiformes: Characidae) from rio Braço Norte, rio Tapajós Basin, with Comments on the Fish Endemism of Serra do Cachimbo Plateau
Moenkhausia guaruba
de Lima, Vita, Dutra, Ohara & Pastana, 2023
DOI: 10.11646/zootaxa.5330.4.6
Researchgate.net/publication/373171540
facebook.com/MuriloPastana
Abstract
A new species of Moenkhausia is described from the rio Braço Norte, a tributary of Rio Teles Pires draining the Serra do Cachimbo, rio Tapajós basin, Pará, Brazil. The new species is diagnosed from all congeners, except M. moisae and M. pirauba, by having a high number of scales in the longitudinal series (43–46 vs. 23–41 in other Moenkhausia species). It can also be distinguished from the aforementioned species based on the combination of the following characters: a single humeral blotch, 21–25 branched anal-fin rays, and a round and symmetrical caudal blotch not continuous anteriorly with the dark midlateral stripe. The new tetra herein described represents an additional, possibly endemic, taxon from the headwaters draining from Serra do Cachimbo, in the Brazilian Shield.
Keywords: Pisces, Amazon Basin, Neotropical fishes, taxonomy, Moenkhausia moisae, Moenkhausia pirauba
Live specimen of Moenkhausia guaruba, MZUSP 119389, paratype, SL uncertain,
Brazil, Pará, Novo Progresso, rio Braço Norte, rio Tapajós basin.
Moenkhausia guaruba, new species
Diagnosis. Moenkhausia guaruba is distinguished from its congeners, except Moenkhausia moisae Géry, Planquette & Le Bail 1995 and Moenkhausia pirauba Zanata, Birindelli & Moreira 2010 by having a higher numberof scales in the longitudinal series (43–46 vs. 23–41 in other Moenkhausia species). The new species differs fromM. moisae by having fewer branched anal-fin rays (21–25, modal 23 vs. 25–29, modal 27 in M. moisae; Fig. 2),a complete and regularly arranged series of predorsal scales (vs. irregular arranged of scales at predorsal region),and by having a single, vertically elongated and relatively wide humeral blotch (vs. two humeral blotches in M.moisae; see Discussion for further details). Moenkhausia guaruba differs from M. pirauba by having a conspicuous,rounded, and symmetrical dark blotch located at the posterior limit of the caudal peduncle and base of caudal-fin rays (vs. caudal blotch horizontally elongated, asymmetrical, continuous anteriorly with midlateral stripe andextending posteriorly to margins of four or five middle caudal-fin rays in M. pirauba), and a thin longitudinal lineformed by dark pigmentation running along horizontal septum of body (vs. dark longitudinal line wide, forming anelongated blotch at caudal peduncle in M. pirauba).
Etymology. The specific name guaruba refers to the Brazilian popular name for Guaruba guarouba Gmelin1788, also known as the Golden Parakeet, a medium-sized golden-yellow Neotropical parrot native to the Brazilian Amazon domain. The name alludes to the intense yellow present on all fins of the new species. A noun inapposition.
Type locality of Moenkhausia guaruba at upper rio Braço Norte at Serra do Cachimbo, tributary of rio Teles Pires, rio Tapajós basin, Pará State, Brazil:
(a) waterfall upstream, substrate composed mainly by rocks; (b) sandy beach downstream to the waterfall.
Arthur de Lima, George Vita, Guilherme M. Dutra, William M. Ohara and Murilo N. L. Pastana. 2023. A New Moenkhausia (Characiformes: Characidae) from rio Braço Norte, rio Tapajós Basin, with Comments on the Fish Endemism of Serra do Cachimbo Plateau. Zootaxa. 5330(4); 586-596. DOI: 10.11646/zootaxa.5330.4.6
Researchgate.net/publication/373171540_A_new_Moenkhausia_from_rio_Braco_Norte_rio_Tapajos_basin
facebook.com/MuriloPastana/posts/6876825412348215
==========================
Moenkhausia guaruba
de Lima, Vita, Dutra, Ohara & Pastana, 2023
DOI: 10.11646/zootaxa.5330.4.6
Researchgate.net/publication/373171540
facebook.com/MuriloPastana
Abstract
A new species of Moenkhausia is described from the rio Braço Norte, a tributary of Rio Teles Pires draining the Serra do Cachimbo, rio Tapajós basin, Pará, Brazil. The new species is diagnosed from all congeners, except M. moisae and M. pirauba, by having a high number of scales in the longitudinal series (43–46 vs. 23–41 in other Moenkhausia species). It can also be distinguished from the aforementioned species based on the combination of the following characters: a single humeral blotch, 21–25 branched anal-fin rays, and a round and symmetrical caudal blotch not continuous anteriorly with the dark midlateral stripe. The new tetra herein described represents an additional, possibly endemic, taxon from the headwaters draining from Serra do Cachimbo, in the Brazilian Shield.
Keywords: Pisces, Amazon Basin, Neotropical fishes, taxonomy, Moenkhausia moisae, Moenkhausia pirauba
Live specimen of Moenkhausia guaruba, MZUSP 119389, paratype, SL uncertain,
Brazil, Pará, Novo Progresso, rio Braço Norte, rio Tapajós basin.
Moenkhausia guaruba, new species
Diagnosis. Moenkhausia guaruba is distinguished from its congeners, except Moenkhausia moisae Géry, Planquette & Le Bail 1995 and Moenkhausia pirauba Zanata, Birindelli & Moreira 2010 by having a higher numberof scales in the longitudinal series (43–46 vs. 23–41 in other Moenkhausia species). The new species differs fromM. moisae by having fewer branched anal-fin rays (21–25, modal 23 vs. 25–29, modal 27 in M. moisae; Fig. 2),a complete and regularly arranged series of predorsal scales (vs. irregular arranged of scales at predorsal region),and by having a single, vertically elongated and relatively wide humeral blotch (vs. two humeral blotches in M.moisae; see Discussion for further details). Moenkhausia guaruba differs from M. pirauba by having a conspicuous,rounded, and symmetrical dark blotch located at the posterior limit of the caudal peduncle and base of caudal-fin rays (vs. caudal blotch horizontally elongated, asymmetrical, continuous anteriorly with midlateral stripe andextending posteriorly to margins of four or five middle caudal-fin rays in M. pirauba), and a thin longitudinal lineformed by dark pigmentation running along horizontal septum of body (vs. dark longitudinal line wide, forming anelongated blotch at caudal peduncle in M. pirauba).
Etymology. The specific name guaruba refers to the Brazilian popular name for Guaruba guarouba Gmelin1788, also known as the Golden Parakeet, a medium-sized golden-yellow Neotropical parrot native to the Brazilian Amazon domain. The name alludes to the intense yellow present on all fins of the new species. A noun inapposition.
Type locality of Moenkhausia guaruba at upper rio Braço Norte at Serra do Cachimbo, tributary of rio Teles Pires, rio Tapajós basin, Pará State, Brazil:
(a) waterfall upstream, substrate composed mainly by rocks; (b) sandy beach downstream to the waterfall.
Arthur de Lima, George Vita, Guilherme M. Dutra, William M. Ohara and Murilo N. L. Pastana. 2023. A New Moenkhausia (Characiformes: Characidae) from rio Braço Norte, rio Tapajós Basin, with Comments on the Fish Endemism of Serra do Cachimbo Plateau. Zootaxa. 5330(4); 586-596. DOI: 10.11646/zootaxa.5330.4.6
Researchgate.net/publication/373171540_A_new_Moenkhausia_from_rio_Braco_Norte_rio_Tapajos_basin
facebook.com/MuriloPastana/posts/6876825412348215
==========================
Ophiocara gigas & O. macrostoma • The Genus Ophiocara (Gobiiformes: Butidae) in Japan, with Descriptions of Two New Species
Ophiocara ophicephalus (Valenciennes in Cuvier & Valenciennes, 1837)
Ophiocara gigas
Ophiocara macrostoma
Kobayashi & Sato, 2023
DOI: 10.1007/s10228-023-00919-z
twitter.com/agoblind
Abstract
A taxonomic review of the genus Ophiocara Gill 1863 in Japan resulted in a revised diagnosis for Ophiocara ophicephalus (Valenciennes in Cuvier and Valenciennes 1837) and descriptions of two new species, Ophiocara gigas and Ophiocara macrostoma, from the Ryukyu Archipelago. The three species are genetically isolated based on the mitochondrial COI region, being distinguished from each other and other congeners by differing combinations of opercular scale morphology, upper jaw length, caudal fin length, and coloration: Ophiocara ophicephalus is characterized by having ctenoid scales on the operculum and distinct silver or white spots on the head, body, and dorsal and caudal fins, and in juveniles the absence of bright markings on the lower part of the caudal fin base; O. gigas by two broad beige bands on the body, black spots scattered on the trunk, and in juveniles the presence of three bright markings on the caudal fin base; and O. macrostoma by a uniformly dark caudal fin, elongated upper jaw in adults (16.0–17.5% of standard length), and in juveniles the presence of two narrow bright bands on the body and three bright markings on the caudal fin base. One of two distinct color patterns, previously thought to represent intraspecific dimorphism of O. ophicephalus, is now considered characteristic of the new species O. gigas. The three species also exhibited distinct habitats, salinity preference, and maximum body length.
Keywords: Ophiocara gigas, Ophiocara macrostoma, Taxonomy, Phylogeny, Mangrove
Ophiocara ophicephalus (Valenciennes in Cuvier and Valenciennes 1837)
(English name: Spangled Gudgeon;
standard Japanese name: Hoshi-madara-haze)
Distribution. Ophiocara ophicephalus is distributed within the Indo-Pacific region, reliable records including Japan (Ryukyu Archipelago: Yakushima, Tanegashima, Okinawa, Kume, Miyako, Irabu, Ishigaki, Iriomote, and Yonaguni islands), Taiwan, the Philippines (Guimaras, Nabunot, Cebu, and Basilan islands), Palau, Cambodia, Thailand, Singapore, Malaysia (Borneo and Tioman islands), Indonesia (Java, Bali, Ceram, and Sulawesi islands), Australia (northern Australia and Lizard Island), the Solomon Islands, and New Caledonia.
Ophiocara gigas sp. nov.
(New English name: Giant Mud-gudgeon;
new standard Japanese name: Kumo-madara-haze)
Etymology. The specific name “gigas” refers to the adult maximum size in this species, being greater than those of congeners.
Distribution. Ophiocara gigas is distributed in the Indo-Pacific region, reliable records being known from Japan (Ryukyu Archipelago: Amami-oshima, Okinawa, Zamami, Kume, Ishigaki, Iriomote, and Yonaguni islands), the Philippines (Luzon Island), Palau, Micronesia, Indonesia (Peling Island off eastern Sulawesi, and Western Papua), the Solomon Islands, Fiji, Vanuatu, and New Caledonia. This species might be recorded from Papua New Guinea (New Ireland) (see discussion).
Ophiocara macrostoma sp. nov.
(New English name: Dark-fin Gudgeon;
new standard Japanese name: Yami-madara-haze)
Etymology. The specific name “macrostoma” refers to the large mouth and relatively long jaw in this species.
Distribution. Ophiocara macrostoma is currently known only from Yakushima, Tanegashima, Ishigaki, Iriomote, and Yonaguni islands in the Ryukyu Archipelago, Japan.
Hirozumi Kobayashi and Mao Sato. 2023. The Genus Ophiocara (Teleostei: Butidae) in Japan, with Descriptions of Two New Species. Ichthyological Research. DOI: 10.1007/s10228-023-00919-z
twitter.com/agoblind/status/1690217286463037440
==========================
Ophiocara ophicephalus (Valenciennes in Cuvier & Valenciennes, 1837)
Ophiocara gigas
Ophiocara macrostoma
Kobayashi & Sato, 2023
DOI: 10.1007/s10228-023-00919-z
twitter.com/agoblind
Abstract
A taxonomic review of the genus Ophiocara Gill 1863 in Japan resulted in a revised diagnosis for Ophiocara ophicephalus (Valenciennes in Cuvier and Valenciennes 1837) and descriptions of two new species, Ophiocara gigas and Ophiocara macrostoma, from the Ryukyu Archipelago. The three species are genetically isolated based on the mitochondrial COI region, being distinguished from each other and other congeners by differing combinations of opercular scale morphology, upper jaw length, caudal fin length, and coloration: Ophiocara ophicephalus is characterized by having ctenoid scales on the operculum and distinct silver or white spots on the head, body, and dorsal and caudal fins, and in juveniles the absence of bright markings on the lower part of the caudal fin base; O. gigas by two broad beige bands on the body, black spots scattered on the trunk, and in juveniles the presence of three bright markings on the caudal fin base; and O. macrostoma by a uniformly dark caudal fin, elongated upper jaw in adults (16.0–17.5% of standard length), and in juveniles the presence of two narrow bright bands on the body and three bright markings on the caudal fin base. One of two distinct color patterns, previously thought to represent intraspecific dimorphism of O. ophicephalus, is now considered characteristic of the new species O. gigas. The three species also exhibited distinct habitats, salinity preference, and maximum body length.
Keywords: Ophiocara gigas, Ophiocara macrostoma, Taxonomy, Phylogeny, Mangrove
Ophiocara ophicephalus (Valenciennes in Cuvier and Valenciennes 1837)
(English name: Spangled Gudgeon;
standard Japanese name: Hoshi-madara-haze)
Distribution. Ophiocara ophicephalus is distributed within the Indo-Pacific region, reliable records including Japan (Ryukyu Archipelago: Yakushima, Tanegashima, Okinawa, Kume, Miyako, Irabu, Ishigaki, Iriomote, and Yonaguni islands), Taiwan, the Philippines (Guimaras, Nabunot, Cebu, and Basilan islands), Palau, Cambodia, Thailand, Singapore, Malaysia (Borneo and Tioman islands), Indonesia (Java, Bali, Ceram, and Sulawesi islands), Australia (northern Australia and Lizard Island), the Solomon Islands, and New Caledonia.
Ophiocara gigas sp. nov.
(New English name: Giant Mud-gudgeon;
new standard Japanese name: Kumo-madara-haze)
Etymology. The specific name “gigas” refers to the adult maximum size in this species, being greater than those of congeners.
Distribution. Ophiocara gigas is distributed in the Indo-Pacific region, reliable records being known from Japan (Ryukyu Archipelago: Amami-oshima, Okinawa, Zamami, Kume, Ishigaki, Iriomote, and Yonaguni islands), the Philippines (Luzon Island), Palau, Micronesia, Indonesia (Peling Island off eastern Sulawesi, and Western Papua), the Solomon Islands, Fiji, Vanuatu, and New Caledonia. This species might be recorded from Papua New Guinea (New Ireland) (see discussion).
Ophiocara macrostoma sp. nov.
(New English name: Dark-fin Gudgeon;
new standard Japanese name: Yami-madara-haze)
Etymology. The specific name “macrostoma” refers to the large mouth and relatively long jaw in this species.
Distribution. Ophiocara macrostoma is currently known only from Yakushima, Tanegashima, Ishigaki, Iriomote, and Yonaguni islands in the Ryukyu Archipelago, Japan.
Hirozumi Kobayashi and Mao Sato. 2023. The Genus Ophiocara (Teleostei: Butidae) in Japan, with Descriptions of Two New Species. Ichthyological Research. DOI: 10.1007/s10228-023-00919-z
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Description of a new species of Schizodon (Characiformes: Anostomidae) from the upper rio Tapajós basin, Brazil PISCESSYSTEMATICSTAXONOMYANOSTOMOIDEASCHIZODON FASCIATUSSCHIZODON TRIVITTATUS AbstractA new species of Schizodon with five dark transverse blotches on the body and a large black blotch at the end of the caudal peduncle is described from the rio Arinos, upper rio Tapajós basin, in the Brazilian Amazon. The new species shares a color pattern composed by transverse brown bars and a caudal fin blotch with Schizodon fasciatus and S. trivittatus but possess twelve rows of scales around the caudal peduncle, a unique character among the species of genus.
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New species of Monomitopus (Ophidiidae) from Hawaiʻi, with the description of a larval coiling behaviorPISCESBLACKWATERCOIIANNIELLO’S COILINTEGRATIVE TAXONOMYMONOMITOPUS AGASSIZIIAbstractIn 1985, Carter and Cohen noted that there are several yet-to-be described species of Monomitopus (Ophidiidae), including one from Hawaiʻi. Recently, blackwater divers collected a larval fish off Kona, Hawaiʻi, similar to the previously described larvae of M. kumae, but DNA sequence data from the larva does not match any of the six previously sequenced species within the genus. Within the Smithsonian Institution’s National Museum of Natural History Ichthyology Collection, we find a single unidentified adult specimen of Monomitopus collected North of Maui, Hawaiʻi in 1972 whose fin-ray and vertebral/myomere counts overlap those of the larval specimen. We describe this new Hawaiian species of Monomitopus based on larval and adult characters. Additionally, blackwater photographs of several species of Monomitopus show the larvae coiled into a tight ball, a novel behavior to be observed in cusk-eels. We describe this behavior, highlighting the importance of blackwater photography in advancing our understanding of marine larval fish biology.
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Pliocene goodeid from MexicoA Pliocene goodeid fish of the Paleolake Amajac, Sanctórum, Hidalgo, Mexico
Carmen Caballero-Viñas, Jesús Alvarado-Ortega, and Kleyton Magno Cantalice Severiano
Article number: 26.2.a30
https://doi.org/10.26879/1259
Copyright Paleontological Society, August 2023
Author biographies
Plain-language and multi-lingual abstracts
PDF version
Submission: 16 December 2022. Acceptance: 24 July 2023.
ABSTRACTThe splitfin fossil species Paleocharacodon guzmanae gen. and sp. nov. is erected based on the osteological study of 14 fossil male and female specimens recovered in the Pliocene deposits of the Paleolake Amajac, in Sanctórum, Hidalgo, Mexico. This new cyprinodontiform fish exhibits the diagnostic features of the family Goodeidae and subfamily Goodeinae; like all the goodeids, its premaxilla has a straight distal end, and its premaxillary ascending process is small; and, like the goodeines, this new species was viviparous, its first anal fin ray is rudimentary, and the males show an andropodium. Although P. guzmanae displays numerous primitive features, it is not possible to place it in any of the goodeine tribes, which currently are vaguely defined by osteological features. This new species seems to be closely related to Characodon; both share a peculiar osteological character; the articular facet for the quadrate is a donut-like structure, in which the retroarticular forms the central region, and a couple of semicircular anguloarticular processes form the surrounding part. This species differs from other goodeids mainly in two features; it has a posttemporal bone with small anteroventral processes, and the openings of its supraorbital canal show the formula1-2a, 2b-3a, 3b-4a, 4b-5a, and 5b-7. The discovery of this extinct goodeid species in the great Pánuco-Salado Basin on the eastern slope of Mexican territory represents an unexpected historical element.
Full paper at:-palaeo-electronica.org/content/current-in-press-articles/3919-pliocene-goodeid-from-mexico
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New occurrences of the endangered Notholebias minimus (Cyprinodontiformes: Rivulidae) in coastal plains of the State of Rio de Janeiro, Brazil: populations features and conservation
AUTHORSHIPSCIMAGO INSTITUTIONS RANKINGS AbstractNotholebias minimus is an endangered annual killifish endemic to the coastal plains of the State of Rio de Janeiro, Brazil. This study aimed to present new occurrences in the Atlantic Forest biome, provide unprecedented population features (body and egg size, fecundity, sexual ratio, and length-weight relationship – LWR), and compare changes in land use and coverage between 1985 and 2021 in biotopes located inside and outside protected areas. Three new occurrence localities were found in shallow temporary wetlands with acidic pH (6.4 ± 0.2) and low concentrations of dissolved oxygen (2.0 ± 0.9 mg/L). Males and females total length ranged from 11.1 to 31 mm and 11 to 26 mm, respectively. Batch fecundity ranged from 18 to 40 oocytes (24.8 ± 8.8), corresponding to oocytes with sizes between 800–1,006 µm (905 ± 56). Males were significantly larger than females (W = 2193.5, p = 0.0067), but both sexes occurred in similar proportions (p = 0.472). LWR showed positive allometry (b = 3.18). Biotopes located within protected areas exhibited higher conservation. Our discoveries expand the knowledge about habitat and population features of N. minimus and reinforce the importance of establishing protected areas for the conservation of annual fish biotopes.
Keywords:
Annual fish; Atlantic Forest biome; Conservation units; Killifish; Threatened fauna
ResumoNotholebias minimus é um peixe anual ameaçado de extinção, endêmico das planícies costeiras do Estado do Rio de Janeiro, Brasil. Neste estudo, objetivamos apresentar novas ocorrências no bioma Mata Atlântica, fornecer características populacionais inéditas (tamanho do corpo e dos ovos, fecundidade, proporção sexual e relação peso-comprimento), e comparar mudanças no uso e cobertura do solo entre 1985 e 2021 em biótopos localizados dentro e fora de unidades de conservação. Registramos três novos locais em áreas úmidas temporárias rasas com pH ácido (6,4 ± 0,2) e baixas concentrações de oxigênio dissolvido (2,0 ± 0,9 mg/L). O comprimento total de machos e fêmeas variou de 11,1 a 31 mm e de 11 a 26 mm, respectivamente. A fecundidade do lote variou entre 18–40 oócitos (24,8 ± 8,8), correspondendo a diâmetros entre 800–1.006 µm (905 ± 56). Os machos foram significativamente maiores que as fêmeas (W = 2193,5; p = 0,0067), mas ocorreram em proporções similares (p = 0,472). A relação peso-comprimento detectou alometria positiva (b = 3,18). Biótopos localizados dentro de áreas protegidas exibiram maior preservação ambiental. Nossas descobertas ampliam o conhecimento sobre as características do habitat e da população de N. minimus e reforçam a importância do estabelecimento de áreas protegidas para a conservação dos biótopos dos peixes anuais.
Palavras-chave:
Bioma Mata Atlântica; Fauna ameaçada; Peixes anuais; Peixes das nuvens; Unidades de conservação
INTRODUCTIONRivulidae (Cyprinodontiformes) is the ninth most specious fish family in the world with about 473 valid species (Fricke et al., 2023), occurring between southern Florida and southeast of the province of Buenos Aires (Costa, 2011; Calviño et al., 2016; Loureiro et al., 2018). Brazil is home to the largest component of this rich fish family, with at least 314 species distributed across all national biomes. This high richness is proportional to the anthropic threats. Rivulidae is the family with the highest number of endangered species among all vertebrates that occur in Brazil (ICMBio, 2022). Habitat loss and fragmentation are the main threats to rivulids (Costa, 2009). Wetlands have been drastically destroyed, both in agricultural areas and in areas undergoing urbanization, through deforestation, drainage, and landfills (Abrantes et al., 2020; Castro, Polaz, 2020; Guedes t al., 2020; Drawert, 2022). Despite this, research, funding agencies, policy, and freshwater conservation have historically neglected wetlands and focused on larger water bodies and flagship species (Guedes et al., 2023).
Rivulidae is commonly subdivided into two major groups: annual/seasonal vs. non-annual/perennial, according to the presence or absence of resistant eggs capable of carrying out a complex process of embryonic diapause during the life cycle (Loureiro et al., 2018). Embryonic diapause allows species to live in hydrologically ephemeral habitats, such as temporary wetlands, where eggs are able to remain buried in dry substrate for months waiting for environmental triggers for hatching (Furness, 2016; Ishimatsu et al., 2018). This uniqueness makes annual species “invisible” during a considerable part of their life cycle, making it difficult to map species distribution areas.
The coastal plains of the State of Rio de Janeiro, located in south-eastern Brazil, are important hotspots of annual fish diversity (Costa, 2012). Among these endemic species, the genus NotholebiasCosta, 2008 stands out including four valid species: Notholebias minimus (Myers, 1942), N. cruzi (Costa, 1988), N. fractifasciatus (Costa, 1988), and N. vermiculatusCosta Amorim, 2013. All of these species are endemic to the Brazilian Atlantic Forest biome and are threatened with extinction (ICMBio, 2018, 2022). There are significant gaps in knowledge regarding the distribution, habitats, life history, and ecology of Notholebias species, as well as for most annual fish. These gaps are aggravated when considering the high number of endangered species, which should reflect a greater effort in and ex situ studies to support conservation strategies. To reduce these knowledge bottlenecks, this study has as main aims (i) to present new occurrence sites of N. minimus in the Brazilian Atlantic Forest biome, (ii) to provide unprecedented population features (individual size, fecundity and egg size, sex ratio, and length-weight ratio), and (iii) to compare anthropic impacts on land use and cover between 1985 and 2021 in temporary wetlands located inside and outside protected areas, which pose a threat to the conservation of this species.
MATERIAL AND METHODSSampling. Fish samplings were conducted between February and December 2022 at 23 sites distributed in five localities in the coastal drainages of Sepetiba Bay and Lagoon System of Jacarepaguá (municipalities of Seropédica and Rio de Janeiro, State of Rio de Janeiro; Tab. 1). Three localities were visited for the first time during this study: Brisas APA (Área Proteção Ambiental das Brisas), UFRRJ (Universidade Federal Rural do Rio de Janeiro), and Chaperó (Chaperó solar power plant). Two other localities with previously known distribution of N. minimus were revisited: PMN Bosque da Barra (Parque Natural Municipal Bosque da Barra) and REBIO Guaratiba (Reserva Biológica Estadual de Guaratiba). The climate is seasonal tropical, with rainy summers and dry winters (Aw climate, according to the Köppen – Geiger classification). Fish were collected with immersion nets (hand nets with an oval shape, 50 x 40 cm, 1 mm of panel mesh size). After capture, they were anesthetized with hydrochloride benzocaine (50 mg/l), euthanized and fixed in 10% formalin in situ. In the laboratory, the fish were measured (precision 0.01 cm), weighed (precision 0.001 g), and after 48 h, preserved in 70% ethanol. Biometric analyses were conducted on the same day as the capture to avoid biases associated with specimen fixation/preservation. In order to reduce the impacts of sampling on fish populations, approximately 75% of specimens were returned alive to the pools after being counted (abundance). Fish were identified and sexed according to Costa ( 1988, 2008, 2009). Vouchers were deposited in the Ichthyological Collection of the Laboratório de Ecologia de Peixes of the Universidade Federal Rural do Rio de Janeiro (LEP–UFRRJ 2588–2593) and are available for online consultation via Global Biodiversity Information Facility – GBIF ( Araújo et al., 2023 ). Additional records were obtained from the bibliography (Costa, Amorim, 2013; Costa, 2016) and online fish collections database search at Sistema de Informação sobre a Biodiversidade Brasileira – SiBBr (www.sibbr.gov.br), SpeciesLink (www.splink.org.br), and GBIF (www.gbif.org).
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TABLE 1 |
Localities, number, and date (month/year) of samplings conducted in attempts to capture Notholebias minimus in coastal drainages of the State of Rio de Janeiro. Brisas APA = Área de Proteção Ambiental das Brisas; PNM Bosque da Barra = Parque Natural Municipal Bosque da Barra; REBIO Guaratiba = Reserva Biológica Estadual de Guaratiba; UFRRJ = Universidade Federal Rural do Rio de Janeiro.
To assess fecundity, ovaries from spawning females (N = 5) were removed from the visceral cavity, weighted, and kept in Gilson’s solution until a complete detachment of oocytes from epithelial and ovarian walls. Eggs were counted and measured (diameter, in μm) in a microscope LEICA TL5000 Ergo. Microanatomy of the zona pellucida was examined under scanning electron microscopy Hitachi TM1000. The bath fecundity (BF), i.e., the number of eggs produced in a single spawning batch, was established from the counting of vitellogenic oocytes (Rizzo, Bazzoli, 2020). The relative fecundity (RF) was determined by the number of vitellogenic oocytes per body size unit (1 cm).
Physical and chemical water characteristics such as temperature (°C), dissolved oxygen (mg/L), redox potential (mV), pH, electrical conductivity (μS/cm), and turbidity (FTU) were measured using a multiprobe model Hanna HI9829. Depth (cm) was measured using centimeter rulers and a digital probe (SpeedTech SM-5) at the center of the temporary wetland (equidistant from opposite shores). Each environmental variable (physical, chemical, and depth) had the average value calculated from three replicates. The measurements were taken at two sites belonging to the same sampling locality (Chaperó, codes 11–12; Tab. 2) during the dry (June) and rainy season (December) of 2022. Therefore, the environmental data presented here may not fully express the range of variability among different occurrence habitats of the species; however, they certainly provide useful evidence of the environmental characteristics to which annual fish are exposed.
Land use and cover. To assess changes in the landscape in the fish occurrence areas, buffers were established with a radius of 250 m from the centroids of the water body where fish were caught, totaling an analyzed area of ~ 0.1963 km2. In these areas, land use and cover matrices for the years 1985 and 2021 were acquired through the Mapbiomas project (v. 7.0, https://mapbiomas.org). The classification was based on annual mosaics of Landsat satellite images, and the image classification process was carried out automatically through the use of decision tree algorithms of the Random Forest type (Souza et al., 2020). The classification was carried out pixel by pixel, the minimum mapped unit was equivalent to 900 m2 (30 x 30 m). A customized Spatial Reference System (SRS) was used to calculate the areas based on the Albers Projection, with parameters provided by the Instituto Brasileiro de Geografia e Estatística (IBGE). The different classes of land use and cover were grouped into two categories: natural (e.g., Forest formation, Wetlands) and anthropic (e.g., Urban Infrastructure, Pasture and Agriculture), and the rate (%) of progression or regression of anthropic cover (between 1985 and 2021) was compared between areas with different territorial policies (protected vs. unprotected areas). We included in our analyses 11 out of the 13 records (6 protected/conservation units; 5 unprotected areas) presented in Tab. 2. In two instances (codes: 10 and 13; 11 and 12; Tab. 2), the distance between the sites was less than 500 m, and to avoid buffer overlap and spatial redundancy in our analyses, we considered only one location. To address potential temporal biases of protected areas created after 1985, we observed if there were conspicuous changes in land use and cover between 1985 and the year of establishment of the protected area. We noticed that the land use and land cover matrices were similar between our lower limit (1985) and the date of creation of the conservation units. Therefore, we conducted our analyses by maintaining a standardized temporal scope of comparison of 36 years (1985–2021) for all 11 locations. All geoprocessing analyses, such as creating buffers, reprojections, transforming raster’s into polygons, calculating areas of land use and cover classes, overlays, and layer sampling were performed using QGIS software v. 3.10 A Coruña (QGIS Development Team, 2022).
Statistical analyses. A Mann-Whitney-Wilcoxon test was performed to compare the differences in the total body length (TL) between males and females. A possible bias in the population sex ratio was assessed by comparing the expected rate of 1:1, and tested with a chi-square test (χ2), with a 95% of the significance level. The length-weight (W = a × TLb) relationships (LWR) based on measurements of 43 individuals (males + females) was estimated by linear regression on the transformed equation: log (W) = log (a) + b log (TL) (Le Cren, 1951), where W is the body weight (g), TL is the total length (cm), a is the y-intercept, and b is the slope (Froese, 2006). All statistical analyses were conducted in an R environment (R Development Core Team, 2022).
RESULTSThree new localities of occurrence of Notholebias minimus were discovered in coastal plains draining into the Sepetiba Bay, State of the Rio de Janeiro (Tab. 2; Fig. 1). Two of the new records occurred in the Seropédica Municipality: (i) inside the campus of the UFRRJ (22°46’38.4”S 43°41’03.4”W; Tab. 2, cod. 8 and 9); and (ii) on land scheduled to receive the installation of the Chaperó solar power plant (22°48’31.0”S 43°45’51.0”W; Tab. 2, codes 11–12). The third new record occurred in the Rio de Janeiro Municipality, in the Brisas APA (22°59’29.5”S 43°39’06.8”W; Tab. 2, codes 10 and 13). In these localities, a total of 156 individuals of N. minimus (70 males, 84 females, and two juveniles with undefined sex; Fig. 2) were sampled. Two localities with the previously known distribution of the species were also revisited (code 3, REBIO de Guaratiba; code 13, PNM Bosque da Barra), however, the species was not recaptured there. Among the 23 sites inspected during the study period (Tab. 1), N. minimus was recorded in only six sites (Tab. 2). Other localities shown in Tab. 2 and Fig. 1, and not mentioned here, were not inspected.
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TABLE 2 |
Records of Notholebias minimus in different areas (AP – protected/conservation units; UN – unprotected) in coastal drainages in the State of Rio de Janeiro. Year of establishment of the protect area also indicated. APA Tabebuias = Área de Proteção Ambiental das Tabebuias; Brisas APA = Área de Proteção Ambiental das Brisas; FLONA Mário Xavier = Floresta Nacional Mário Xavier; PNM Bosque da Barra = Parque Natural Municipal Bosque da Barra; REBIO Guaratiba = Reserva Biológica Estadual de Guaratiba. ZUEC-PIS, Coleção de Peixes do Museu de Zoologia of the Universidade Estadual de Campinas; MNRJ, Museu Nacional, Rio de Janeiro; UFRJ, Universidade Federal do Rio de Janeiro - Instituto de Biologia; LEP-UFRRJ, Coleção Ictioló gica do Laboratório de Ecologia de Peixes of the Universidade Federal Rural do Rio de Janeiro. *New records presented in this study.
FIGURE 1 |
Map of occurrences of Notholebias minimus in coastal plains of the State of Rio de Janeiro, Brazil. Black triangles indicate the new records in this study. Black dots, records from previous studies (e.g., Costa, Amorim, 2013; Costa, 2016). Occurrence references (codes) are available in Tab. 2.
FIGURE 2 |
Males of Notholebias minimus captured in (A) Área de Proteção Ambiental das Brisas, Rio de Janeiro Municipality, and (B) in the campus of the Universidade Federal Rural do Rio de Janeiro – UFRRJ (Seropédica Municipality). Scale bar = 4 mm.
Notholebias minimus was recorded in temporary pools typical of annual killifishes, including unshaded (Fig. 3A–B) and shaded swamps in the interior/edges of small forest fragments. Floating macrophytes were present only in unshaded swamps (Fig. 3A). For the Chaperó locality, depth (cm) varied between the dry (average ± s.d., 33 ± 19 cm) and wet (85 ± 21 cm) seasons, with swamps reaching up to 105 cm in depth (Tab. 3). Physical and chemical water characteristics indicate a pH with an acidity tendency (minimum-maximum, 6.25–6.76) and low oxygen concentrations (1.1–3.8 mg/ L; Tab. 3). Other non-annual fish species occurred in sympatry with N. minimus, such as Trichopodus trichopterus (Pallas, 1770) in the Brisas APA; Phalloceros anisophallos Lucinda, 2008, Hyphessobrycon bifasciatus Ellis, 1911, and Deuterodon hastatus (Myers, 1928) in the Seropédica Municipality (Chaperó and UFRRJ localities).
FIGURE 3 |
Temporary wetlands in the Guandu River Hydrographic Region (coastal drainages of the Sepetiba Bay, State of Rio de Janeiro, Brazil) with new occurrences of Notholebias minimus. A–B. Swamps of open vegetation in Chaperó locality, C–D. Swamps in forest fragments in the campus of the Universidade Federal Rural do Rio de Janeiro – UFRRJ, and in the Área de Proteção Ambiental das Brisas, respectively.
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TABLE 3 |
Physical and chemical water characteristics in the temporary wetlands associated with captures of Notholebias minimus in the Chaperó locality (codes 11-12; Tab. 2), during the dry (June) and wet (December) seasons of 2022. Minimum– maximum (mean ± standard deviation).
The chi-square test did not show significant differences in the sex ratio (1.1 female: 1 male), with both sexes being captured in similar proportions (χ2 = 0.516, p = 0.472). The body size ranged from 11.1 to 31 mm (mean ± s.d., 19.1 ± 3.9 mm TL) and 11 to 26 mm (17.5 ± 3.0 mm TL), for males and females respectively. The mean body size of males was significantly larger than females (W = 2193.5, p = 0.0067). The length-weight relationship (LWR) with sexes pooled was determined by the following equation fitted to a potential curve: Wt = 0.0099 × TL 3.18 (N = 43; Fig. 4). This equation corresponds to the logarithmic form, ln W = 4.61 + 3.18 × ln L (R2= 0.92). Notholebias minimus exhibits positive allometric growth with an exponent parameter (b) equal to 3.18 (2.89–3.46; 95% confidence interval). The total number of oocytes present in the gonads (regardless of the stage of development) of females ranged from 35 to 63 (mean 50 ± 12.3 s.d). The bath fecundity (only vitellogenic oocytes) ranged from 18 to 40 (24.8 ± 8.8), corresponding to oocytes diameter ranging from 800 to 1,006 µm (905 ± 56 µm). Relative fecundity (eggs per body size unit – 1 cm) ranged from 8.1 to 16.6 (10.9 ± 3.3). Oocytes in advanced stages of development have mushroom-like projections and polygonal grooves in the zona pellucida (Fig. 5).
Seven different classes of land use and cover were mapped in adjacent areas (radius 250 m) of N. minimus occurrences (Fig. 6). The main impacts in the species occurrence areas were mosaic of land use (28.2%; areas of agricultural use where it was not possible to distinguish between pasture and agriculture), pasture (21.7%), urban area (4.8%) and other non-vegetated areas (3.2%; areas of non-permeable surfaces such as infrastructure or mining). The locations within conservation units exhibited greater relative coverage of natural matrices (total 48%; wooded sandbank vegetation 18.9%, forest formation 14.7%, and wetlands 14.2%) compared to unprotected sites (total 29.4%; wooded sandbank vegetation 0.26%, forest formation 11.7%, and wetlands 17.2%). Protected and unprotected areas also showed opposite temporal trends (1985–2021) of changes in the landscape, while unprotected areas showed an expansion of 4% of anthropic matrices, in protected areas there was a restoration of 7.3% of natural matrices (Fig. 6).
FIGURE 4 |
Length-weight relationship of Notholebias minimus (N = 43).
FIGURE 5 |
Unfertilized eggs of Notholebias minimus, evidencing mushroom-like projections and polygonal grooves in the zona pellucida. Scale bar = 100 µm.
FIGURE 6 |
Land use and cover (%) in 11 different localities (Protected/Conservation Units vs. Unprotected) and periods (1985–2021) at areas (buffer 250 m) of occurrence of Notholebias minimus.
DISCUSSIONNotholebias minimus has a remarkably wide geographic distribution compared with other species of the genus Notholebias. Records of this species include the basins of the rivers Guandu, Guarda, Portinho, and drainages of the Lagoon System of Jacarepaguá (Costa, 1988; Costa, Amorim, 2013). This contrasts with the other species of the genus, which have lesser wide distribution and are restricted to the surroundings of the type localities (Costa, 1988; Costa, Amorim, 2013; ICMBio, 2018). There are alternative historical scenarios for the modern distribution patterns of Rivulidae (e.g., Garcia et al., 2012; Costa et al., 2017; Loureiro et al., 2018), and at smaller spatial scales, there is evidence that some species could be dispersed by rearrangements of river drainages, large floods or even endozoochory (Costa, 2013; Silva et al., 2019). Therefore, the explanation for the current distribution of Notholebias species is not trivial and deserves further specific studies, as they may encompass unique phylogeographic patterns.
The new biotopes were located inside shaded forest fragments and in swamps of open vegetation exposed to the sun, typical of Notholebias spp., which may still include sandy coastal areas covered by bush, grass and open woodland vegetation located up to 100 m from the sea (Costa, 1988). The water in temporary pools at Chaperó locality showed an acidity tendency and low oxygen concentrations, typical environmental conditions of temporary wetlands (Bidwell, 2013,). Overall, annual killifish have evolved to withstand significant daily and seasonal environmental changes, including variations in temperature, oxygen concentration, salinity, pH, and water availability, that approach the limits of vertebrate survival (Podrabsky et al., 2016; Polačik, Podbrabsky, 2016; Ishimatsuet al., 2018). The co-occurrence between N. minimus and other non-annual species (T. trichopterus, P. anisophallos, H. bifasciatus, D. hastatus) indicates a periodic connection of the temporary wetlands with adjacent perennial water bodies. Sympatry between Notholebias and other annual and non-annual species is common (Costa, 1988; ICMBio, 2018) and indicates that these species are able to complete their life cycle and maintain viable populations even under periodic competition or predation.
Notholebias minimus showed a positive allometric growth (b = 3.18), with comparatively more gain in weight than in length (Froese, 2006). However, no previous references were found for the LWR of N. minimus and other species of Notholebias, what prevents comparisons of our results with other studies. Males of N. minimus are larger than females, corroborating the pattern of sexual dimorphism commonly observed in other species of Rivulidae (e.g., Arenzon et al., 2001; Lanés et al., 2012; Guedes et al., 2020). Preparation for reproduction can cause oxidative stress and affect maternal self-maintenance (Godoy et al., 2020) and consequently the somatic growth of females. Differences in body size mediate the coexistence of annual fish in temporary pools by mitigating intra and interspecific competition (Arenzon et al., 2001; Volcan et al., 2019). Therefore, intraspecific differences observed in body size between males and females may be associated with different reproductive energy costs, in addition to playing an important role in population coexistence.
A reduced batch fecundity (24.8 ± 8.8 eggs) was found for N. minimus, as well as for other annual species such as Cynopoecilus melanotaenia (Regan, 1912) (19 ± 26 eggs; Gonçalves et al., 2011), Austrolebias nigrofasciatus Costa & Cheffe, 2001 (21.5 ± 12 eggs; Volcan et al., 2011), and Leptopanchax opalescens (Myers, 1942) (27 ± 7.0 eggs; Guedes et al., 2023). However, the eggs are relatively large (maximum 1.006 μm) when weighted by the spatial limitations imposed by the coelomic cavity in this species of reduced body size (< 4 cm). According to the optimal egg size theory, populations evolve a particular egg size that balances the tradeoff between egg size and fecundity to maximize reproductive yield (Smith, Fretwell, 1974). Therefore, larger eggs come at a cost of reducing the number of eggs, which is in accordance with the findings of this study. Annual species have smaller eggs when compared to non-annual species of the family Rivulidae (Guedes et al., 2023). This may be associated with the extreme tolerance of embryos to hypoxia due to the process of embryonic diapause, which culminates in developmental arrest, metabolic depression, and G1 cell cycle arrest (Podrabsky et al., 2016). For species without embryonic diapause, the optimal investment in offspring size increases as environmental quality decreases (Rollinson, Hutchings, 2013; Riesch et al., 2014; Santi et al., 2021). The zona pellucida of mature eggs of N. minimus featured mushroom-like projections similar to other species in the genera Leptopanchax and Notholebias (Costa, Leal, 2009; Thompson et al., 2017). Wourms, Sheldon (1976) hypothesized that these projections are a chorionic respiratory system since there is a network of channels leading to hollow spikes that may function as egg-like aeropiles, similar to insect eggs. This may be an adaptation for annual fishes since a thick, hard, and consequently poorly oxygen-permeable zona pellucida may be necessary to prevent desiccation (Thompson et al., 2017).
Notholebias minimus is currently found in five conservation units in the State of Rio de Janeiro, including the unpublished record in the Brisas APA presented here. However, other species such as Notholebias vermiculatus and N. fractifasciatus do not occur in protected areas (ICMBio, 2018). Notholebias cruzi whose type locality is outside a conservation unit, had its biotopes destroyed due to urban expansion and has not been found since 2002, and may be extinct (Costa, 2012; Lira, 2021). Biotopes of N. minimus located inside conservation units show great natural cover and environmental restoration trends between 1985 and 2021. On the other hand, locations without any protection show greater coverage of anthropic matrices (pasture, urban area) and a loss of temporary wetlands between 1985 and 2021. These results show the important role played by protected areas in the conservation of biotopes. However, even the protected areas showed high coverage (52%) of anthropic matrices, which may reflect the type of territorial policy, since part of these units are for sustainable use and consequently have fewer restrictions on land use (SNUC, 2000), and/or historical deforestation prior to 1985, since the Brazilian Atlantic Forest biome is historically impacted (Joly et al., 2014; Egler et al., 2020).
The wide geographic distribution of N. minimus, combined with records in conservation units, places this species in a more favorable conservation position when compared to other species of the genus Notholebias. Our findings reveal that biotopes located within protected areas show a trend of restoration between 1985–2021, with an advancement of natural matrices. Conversely, biotopes found in unprotected areas show an opposite trend, with an increase in anthropogenic impacts on land use and coverage. However, it is crucial to maintain continuous monitoring of the biotopes, both inside and outside protected areas, to ensure the successful preservation of these endangered fish. In conclusion, our findings expand the knowledge of the habitats and population structure of N. minimus, and reinforce the importance of establishing protected areas for the conservation and restoration of annual fish biotopes.
ACKNOWLEDGEMENTSThis research was funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq (Proc. #140512/2022–5; 305712/2020–9; 306792/2021–4), Fundação Carlos Chagas Filho de Amparo à Pesquisa no Estado do Rio de Janeiro – FAPERJ (Proc. E–26/200.897/2021; E–26/202.483/2021), Fundo Brasileiro para a Biodiversidade – FUNBIO Conservando o Futuro, and Instituto HUMANIZE (Proc. # 028/2023). Special thanks to Yuri Borba for photographing the fish and habitat at Área de Proteção Ambiental das Brisas.
REFERENCES
AUTHORSHIPSCIMAGO INSTITUTIONS RANKINGS AbstractNotholebias minimus is an endangered annual killifish endemic to the coastal plains of the State of Rio de Janeiro, Brazil. This study aimed to present new occurrences in the Atlantic Forest biome, provide unprecedented population features (body and egg size, fecundity, sexual ratio, and length-weight relationship – LWR), and compare changes in land use and coverage between 1985 and 2021 in biotopes located inside and outside protected areas. Three new occurrence localities were found in shallow temporary wetlands with acidic pH (6.4 ± 0.2) and low concentrations of dissolved oxygen (2.0 ± 0.9 mg/L). Males and females total length ranged from 11.1 to 31 mm and 11 to 26 mm, respectively. Batch fecundity ranged from 18 to 40 oocytes (24.8 ± 8.8), corresponding to oocytes with sizes between 800–1,006 µm (905 ± 56). Males were significantly larger than females (W = 2193.5, p = 0.0067), but both sexes occurred in similar proportions (p = 0.472). LWR showed positive allometry (b = 3.18). Biotopes located within protected areas exhibited higher conservation. Our discoveries expand the knowledge about habitat and population features of N. minimus and reinforce the importance of establishing protected areas for the conservation of annual fish biotopes.
Keywords:
Annual fish; Atlantic Forest biome; Conservation units; Killifish; Threatened fauna
ResumoNotholebias minimus é um peixe anual ameaçado de extinção, endêmico das planícies costeiras do Estado do Rio de Janeiro, Brasil. Neste estudo, objetivamos apresentar novas ocorrências no bioma Mata Atlântica, fornecer características populacionais inéditas (tamanho do corpo e dos ovos, fecundidade, proporção sexual e relação peso-comprimento), e comparar mudanças no uso e cobertura do solo entre 1985 e 2021 em biótopos localizados dentro e fora de unidades de conservação. Registramos três novos locais em áreas úmidas temporárias rasas com pH ácido (6,4 ± 0,2) e baixas concentrações de oxigênio dissolvido (2,0 ± 0,9 mg/L). O comprimento total de machos e fêmeas variou de 11,1 a 31 mm e de 11 a 26 mm, respectivamente. A fecundidade do lote variou entre 18–40 oócitos (24,8 ± 8,8), correspondendo a diâmetros entre 800–1.006 µm (905 ± 56). Os machos foram significativamente maiores que as fêmeas (W = 2193,5; p = 0,0067), mas ocorreram em proporções similares (p = 0,472). A relação peso-comprimento detectou alometria positiva (b = 3,18). Biótopos localizados dentro de áreas protegidas exibiram maior preservação ambiental. Nossas descobertas ampliam o conhecimento sobre as características do habitat e da população de N. minimus e reforçam a importância do estabelecimento de áreas protegidas para a conservação dos biótopos dos peixes anuais.
Palavras-chave:
Bioma Mata Atlântica; Fauna ameaçada; Peixes anuais; Peixes das nuvens; Unidades de conservação
INTRODUCTIONRivulidae (Cyprinodontiformes) is the ninth most specious fish family in the world with about 473 valid species (Fricke et al., 2023), occurring between southern Florida and southeast of the province of Buenos Aires (Costa, 2011; Calviño et al., 2016; Loureiro et al., 2018). Brazil is home to the largest component of this rich fish family, with at least 314 species distributed across all national biomes. This high richness is proportional to the anthropic threats. Rivulidae is the family with the highest number of endangered species among all vertebrates that occur in Brazil (ICMBio, 2022). Habitat loss and fragmentation are the main threats to rivulids (Costa, 2009). Wetlands have been drastically destroyed, both in agricultural areas and in areas undergoing urbanization, through deforestation, drainage, and landfills (Abrantes et al., 2020; Castro, Polaz, 2020; Guedes t al., 2020; Drawert, 2022). Despite this, research, funding agencies, policy, and freshwater conservation have historically neglected wetlands and focused on larger water bodies and flagship species (Guedes et al., 2023).
Rivulidae is commonly subdivided into two major groups: annual/seasonal vs. non-annual/perennial, according to the presence or absence of resistant eggs capable of carrying out a complex process of embryonic diapause during the life cycle (Loureiro et al., 2018). Embryonic diapause allows species to live in hydrologically ephemeral habitats, such as temporary wetlands, where eggs are able to remain buried in dry substrate for months waiting for environmental triggers for hatching (Furness, 2016; Ishimatsu et al., 2018). This uniqueness makes annual species “invisible” during a considerable part of their life cycle, making it difficult to map species distribution areas.
The coastal plains of the State of Rio de Janeiro, located in south-eastern Brazil, are important hotspots of annual fish diversity (Costa, 2012). Among these endemic species, the genus NotholebiasCosta, 2008 stands out including four valid species: Notholebias minimus (Myers, 1942), N. cruzi (Costa, 1988), N. fractifasciatus (Costa, 1988), and N. vermiculatusCosta Amorim, 2013. All of these species are endemic to the Brazilian Atlantic Forest biome and are threatened with extinction (ICMBio, 2018, 2022). There are significant gaps in knowledge regarding the distribution, habitats, life history, and ecology of Notholebias species, as well as for most annual fish. These gaps are aggravated when considering the high number of endangered species, which should reflect a greater effort in and ex situ studies to support conservation strategies. To reduce these knowledge bottlenecks, this study has as main aims (i) to present new occurrence sites of N. minimus in the Brazilian Atlantic Forest biome, (ii) to provide unprecedented population features (individual size, fecundity and egg size, sex ratio, and length-weight ratio), and (iii) to compare anthropic impacts on land use and cover between 1985 and 2021 in temporary wetlands located inside and outside protected areas, which pose a threat to the conservation of this species.
MATERIAL AND METHODSSampling. Fish samplings were conducted between February and December 2022 at 23 sites distributed in five localities in the coastal drainages of Sepetiba Bay and Lagoon System of Jacarepaguá (municipalities of Seropédica and Rio de Janeiro, State of Rio de Janeiro; Tab. 1). Three localities were visited for the first time during this study: Brisas APA (Área Proteção Ambiental das Brisas), UFRRJ (Universidade Federal Rural do Rio de Janeiro), and Chaperó (Chaperó solar power plant). Two other localities with previously known distribution of N. minimus were revisited: PMN Bosque da Barra (Parque Natural Municipal Bosque da Barra) and REBIO Guaratiba (Reserva Biológica Estadual de Guaratiba). The climate is seasonal tropical, with rainy summers and dry winters (Aw climate, according to the Köppen – Geiger classification). Fish were collected with immersion nets (hand nets with an oval shape, 50 x 40 cm, 1 mm of panel mesh size). After capture, they were anesthetized with hydrochloride benzocaine (50 mg/l), euthanized and fixed in 10% formalin in situ. In the laboratory, the fish were measured (precision 0.01 cm), weighed (precision 0.001 g), and after 48 h, preserved in 70% ethanol. Biometric analyses were conducted on the same day as the capture to avoid biases associated with specimen fixation/preservation. In order to reduce the impacts of sampling on fish populations, approximately 75% of specimens were returned alive to the pools after being counted (abundance). Fish were identified and sexed according to Costa ( 1988, 2008, 2009). Vouchers were deposited in the Ichthyological Collection of the Laboratório de Ecologia de Peixes of the Universidade Federal Rural do Rio de Janeiro (LEP–UFRRJ 2588–2593) and are available for online consultation via Global Biodiversity Information Facility – GBIF ( Araújo et al., 2023 ). Additional records were obtained from the bibliography (Costa, Amorim, 2013; Costa, 2016) and online fish collections database search at Sistema de Informação sobre a Biodiversidade Brasileira – SiBBr (www.sibbr.gov.br), SpeciesLink (www.splink.org.br), and GBIF (www.gbif.org).
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TABLE 1 |
Localities, number, and date (month/year) of samplings conducted in attempts to capture Notholebias minimus in coastal drainages of the State of Rio de Janeiro. Brisas APA = Área de Proteção Ambiental das Brisas; PNM Bosque da Barra = Parque Natural Municipal Bosque da Barra; REBIO Guaratiba = Reserva Biológica Estadual de Guaratiba; UFRRJ = Universidade Federal Rural do Rio de Janeiro.
To assess fecundity, ovaries from spawning females (N = 5) were removed from the visceral cavity, weighted, and kept in Gilson’s solution until a complete detachment of oocytes from epithelial and ovarian walls. Eggs were counted and measured (diameter, in μm) in a microscope LEICA TL5000 Ergo. Microanatomy of the zona pellucida was examined under scanning electron microscopy Hitachi TM1000. The bath fecundity (BF), i.e., the number of eggs produced in a single spawning batch, was established from the counting of vitellogenic oocytes (Rizzo, Bazzoli, 2020). The relative fecundity (RF) was determined by the number of vitellogenic oocytes per body size unit (1 cm).
Physical and chemical water characteristics such as temperature (°C), dissolved oxygen (mg/L), redox potential (mV), pH, electrical conductivity (μS/cm), and turbidity (FTU) were measured using a multiprobe model Hanna HI9829. Depth (cm) was measured using centimeter rulers and a digital probe (SpeedTech SM-5) at the center of the temporary wetland (equidistant from opposite shores). Each environmental variable (physical, chemical, and depth) had the average value calculated from three replicates. The measurements were taken at two sites belonging to the same sampling locality (Chaperó, codes 11–12; Tab. 2) during the dry (June) and rainy season (December) of 2022. Therefore, the environmental data presented here may not fully express the range of variability among different occurrence habitats of the species; however, they certainly provide useful evidence of the environmental characteristics to which annual fish are exposed.
Land use and cover. To assess changes in the landscape in the fish occurrence areas, buffers were established with a radius of 250 m from the centroids of the water body where fish were caught, totaling an analyzed area of ~ 0.1963 km2. In these areas, land use and cover matrices for the years 1985 and 2021 were acquired through the Mapbiomas project (v. 7.0, https://mapbiomas.org). The classification was based on annual mosaics of Landsat satellite images, and the image classification process was carried out automatically through the use of decision tree algorithms of the Random Forest type (Souza et al., 2020). The classification was carried out pixel by pixel, the minimum mapped unit was equivalent to 900 m2 (30 x 30 m). A customized Spatial Reference System (SRS) was used to calculate the areas based on the Albers Projection, with parameters provided by the Instituto Brasileiro de Geografia e Estatística (IBGE). The different classes of land use and cover were grouped into two categories: natural (e.g., Forest formation, Wetlands) and anthropic (e.g., Urban Infrastructure, Pasture and Agriculture), and the rate (%) of progression or regression of anthropic cover (between 1985 and 2021) was compared between areas with different territorial policies (protected vs. unprotected areas). We included in our analyses 11 out of the 13 records (6 protected/conservation units; 5 unprotected areas) presented in Tab. 2. In two instances (codes: 10 and 13; 11 and 12; Tab. 2), the distance between the sites was less than 500 m, and to avoid buffer overlap and spatial redundancy in our analyses, we considered only one location. To address potential temporal biases of protected areas created after 1985, we observed if there were conspicuous changes in land use and cover between 1985 and the year of establishment of the protected area. We noticed that the land use and land cover matrices were similar between our lower limit (1985) and the date of creation of the conservation units. Therefore, we conducted our analyses by maintaining a standardized temporal scope of comparison of 36 years (1985–2021) for all 11 locations. All geoprocessing analyses, such as creating buffers, reprojections, transforming raster’s into polygons, calculating areas of land use and cover classes, overlays, and layer sampling were performed using QGIS software v. 3.10 A Coruña (QGIS Development Team, 2022).
Statistical analyses. A Mann-Whitney-Wilcoxon test was performed to compare the differences in the total body length (TL) between males and females. A possible bias in the population sex ratio was assessed by comparing the expected rate of 1:1, and tested with a chi-square test (χ2), with a 95% of the significance level. The length-weight (W = a × TLb) relationships (LWR) based on measurements of 43 individuals (males + females) was estimated by linear regression on the transformed equation: log (W) = log (a) + b log (TL) (Le Cren, 1951), where W is the body weight (g), TL is the total length (cm), a is the y-intercept, and b is the slope (Froese, 2006). All statistical analyses were conducted in an R environment (R Development Core Team, 2022).
RESULTSThree new localities of occurrence of Notholebias minimus were discovered in coastal plains draining into the Sepetiba Bay, State of the Rio de Janeiro (Tab. 2; Fig. 1). Two of the new records occurred in the Seropédica Municipality: (i) inside the campus of the UFRRJ (22°46’38.4”S 43°41’03.4”W; Tab. 2, cod. 8 and 9); and (ii) on land scheduled to receive the installation of the Chaperó solar power plant (22°48’31.0”S 43°45’51.0”W; Tab. 2, codes 11–12). The third new record occurred in the Rio de Janeiro Municipality, in the Brisas APA (22°59’29.5”S 43°39’06.8”W; Tab. 2, codes 10 and 13). In these localities, a total of 156 individuals of N. minimus (70 males, 84 females, and two juveniles with undefined sex; Fig. 2) were sampled. Two localities with the previously known distribution of the species were also revisited (code 3, REBIO de Guaratiba; code 13, PNM Bosque da Barra), however, the species was not recaptured there. Among the 23 sites inspected during the study period (Tab. 1), N. minimus was recorded in only six sites (Tab. 2). Other localities shown in Tab. 2 and Fig. 1, and not mentioned here, were not inspected.
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TABLE 2 |
Records of Notholebias minimus in different areas (AP – protected/conservation units; UN – unprotected) in coastal drainages in the State of Rio de Janeiro. Year of establishment of the protect area also indicated. APA Tabebuias = Área de Proteção Ambiental das Tabebuias; Brisas APA = Área de Proteção Ambiental das Brisas; FLONA Mário Xavier = Floresta Nacional Mário Xavier; PNM Bosque da Barra = Parque Natural Municipal Bosque da Barra; REBIO Guaratiba = Reserva Biológica Estadual de Guaratiba. ZUEC-PIS, Coleção de Peixes do Museu de Zoologia of the Universidade Estadual de Campinas; MNRJ, Museu Nacional, Rio de Janeiro; UFRJ, Universidade Federal do Rio de Janeiro - Instituto de Biologia; LEP-UFRRJ, Coleção Ictioló gica do Laboratório de Ecologia de Peixes of the Universidade Federal Rural do Rio de Janeiro. *New records presented in this study.
FIGURE 1 |
Map of occurrences of Notholebias minimus in coastal plains of the State of Rio de Janeiro, Brazil. Black triangles indicate the new records in this study. Black dots, records from previous studies (e.g., Costa, Amorim, 2013; Costa, 2016). Occurrence references (codes) are available in Tab. 2.
FIGURE 2 |
Males of Notholebias minimus captured in (A) Área de Proteção Ambiental das Brisas, Rio de Janeiro Municipality, and (B) in the campus of the Universidade Federal Rural do Rio de Janeiro – UFRRJ (Seropédica Municipality). Scale bar = 4 mm.
Notholebias minimus was recorded in temporary pools typical of annual killifishes, including unshaded (Fig. 3A–B) and shaded swamps in the interior/edges of small forest fragments. Floating macrophytes were present only in unshaded swamps (Fig. 3A). For the Chaperó locality, depth (cm) varied between the dry (average ± s.d., 33 ± 19 cm) and wet (85 ± 21 cm) seasons, with swamps reaching up to 105 cm in depth (Tab. 3). Physical and chemical water characteristics indicate a pH with an acidity tendency (minimum-maximum, 6.25–6.76) and low oxygen concentrations (1.1–3.8 mg/ L; Tab. 3). Other non-annual fish species occurred in sympatry with N. minimus, such as Trichopodus trichopterus (Pallas, 1770) in the Brisas APA; Phalloceros anisophallos Lucinda, 2008, Hyphessobrycon bifasciatus Ellis, 1911, and Deuterodon hastatus (Myers, 1928) in the Seropédica Municipality (Chaperó and UFRRJ localities).
FIGURE 3 |
Temporary wetlands in the Guandu River Hydrographic Region (coastal drainages of the Sepetiba Bay, State of Rio de Janeiro, Brazil) with new occurrences of Notholebias minimus. A–B. Swamps of open vegetation in Chaperó locality, C–D. Swamps in forest fragments in the campus of the Universidade Federal Rural do Rio de Janeiro – UFRRJ, and in the Área de Proteção Ambiental das Brisas, respectively.
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TABLE 3 |
Physical and chemical water characteristics in the temporary wetlands associated with captures of Notholebias minimus in the Chaperó locality (codes 11-12; Tab. 2), during the dry (June) and wet (December) seasons of 2022. Minimum– maximum (mean ± standard deviation).
The chi-square test did not show significant differences in the sex ratio (1.1 female: 1 male), with both sexes being captured in similar proportions (χ2 = 0.516, p = 0.472). The body size ranged from 11.1 to 31 mm (mean ± s.d., 19.1 ± 3.9 mm TL) and 11 to 26 mm (17.5 ± 3.0 mm TL), for males and females respectively. The mean body size of males was significantly larger than females (W = 2193.5, p = 0.0067). The length-weight relationship (LWR) with sexes pooled was determined by the following equation fitted to a potential curve: Wt = 0.0099 × TL 3.18 (N = 43; Fig. 4). This equation corresponds to the logarithmic form, ln W = 4.61 + 3.18 × ln L (R2= 0.92). Notholebias minimus exhibits positive allometric growth with an exponent parameter (b) equal to 3.18 (2.89–3.46; 95% confidence interval). The total number of oocytes present in the gonads (regardless of the stage of development) of females ranged from 35 to 63 (mean 50 ± 12.3 s.d). The bath fecundity (only vitellogenic oocytes) ranged from 18 to 40 (24.8 ± 8.8), corresponding to oocytes diameter ranging from 800 to 1,006 µm (905 ± 56 µm). Relative fecundity (eggs per body size unit – 1 cm) ranged from 8.1 to 16.6 (10.9 ± 3.3). Oocytes in advanced stages of development have mushroom-like projections and polygonal grooves in the zona pellucida (Fig. 5).
Seven different classes of land use and cover were mapped in adjacent areas (radius 250 m) of N. minimus occurrences (Fig. 6). The main impacts in the species occurrence areas were mosaic of land use (28.2%; areas of agricultural use where it was not possible to distinguish between pasture and agriculture), pasture (21.7%), urban area (4.8%) and other non-vegetated areas (3.2%; areas of non-permeable surfaces such as infrastructure or mining). The locations within conservation units exhibited greater relative coverage of natural matrices (total 48%; wooded sandbank vegetation 18.9%, forest formation 14.7%, and wetlands 14.2%) compared to unprotected sites (total 29.4%; wooded sandbank vegetation 0.26%, forest formation 11.7%, and wetlands 17.2%). Protected and unprotected areas also showed opposite temporal trends (1985–2021) of changes in the landscape, while unprotected areas showed an expansion of 4% of anthropic matrices, in protected areas there was a restoration of 7.3% of natural matrices (Fig. 6).
FIGURE 4 |
Length-weight relationship of Notholebias minimus (N = 43).
FIGURE 5 |
Unfertilized eggs of Notholebias minimus, evidencing mushroom-like projections and polygonal grooves in the zona pellucida. Scale bar = 100 µm.
FIGURE 6 |
Land use and cover (%) in 11 different localities (Protected/Conservation Units vs. Unprotected) and periods (1985–2021) at areas (buffer 250 m) of occurrence of Notholebias minimus.
DISCUSSIONNotholebias minimus has a remarkably wide geographic distribution compared with other species of the genus Notholebias. Records of this species include the basins of the rivers Guandu, Guarda, Portinho, and drainages of the Lagoon System of Jacarepaguá (Costa, 1988; Costa, Amorim, 2013). This contrasts with the other species of the genus, which have lesser wide distribution and are restricted to the surroundings of the type localities (Costa, 1988; Costa, Amorim, 2013; ICMBio, 2018). There are alternative historical scenarios for the modern distribution patterns of Rivulidae (e.g., Garcia et al., 2012; Costa et al., 2017; Loureiro et al., 2018), and at smaller spatial scales, there is evidence that some species could be dispersed by rearrangements of river drainages, large floods or even endozoochory (Costa, 2013; Silva et al., 2019). Therefore, the explanation for the current distribution of Notholebias species is not trivial and deserves further specific studies, as they may encompass unique phylogeographic patterns.
The new biotopes were located inside shaded forest fragments and in swamps of open vegetation exposed to the sun, typical of Notholebias spp., which may still include sandy coastal areas covered by bush, grass and open woodland vegetation located up to 100 m from the sea (Costa, 1988). The water in temporary pools at Chaperó locality showed an acidity tendency and low oxygen concentrations, typical environmental conditions of temporary wetlands (Bidwell, 2013,). Overall, annual killifish have evolved to withstand significant daily and seasonal environmental changes, including variations in temperature, oxygen concentration, salinity, pH, and water availability, that approach the limits of vertebrate survival (Podrabsky et al., 2016; Polačik, Podbrabsky, 2016; Ishimatsuet al., 2018). The co-occurrence between N. minimus and other non-annual species (T. trichopterus, P. anisophallos, H. bifasciatus, D. hastatus) indicates a periodic connection of the temporary wetlands with adjacent perennial water bodies. Sympatry between Notholebias and other annual and non-annual species is common (Costa, 1988; ICMBio, 2018) and indicates that these species are able to complete their life cycle and maintain viable populations even under periodic competition or predation.
Notholebias minimus showed a positive allometric growth (b = 3.18), with comparatively more gain in weight than in length (Froese, 2006). However, no previous references were found for the LWR of N. minimus and other species of Notholebias, what prevents comparisons of our results with other studies. Males of N. minimus are larger than females, corroborating the pattern of sexual dimorphism commonly observed in other species of Rivulidae (e.g., Arenzon et al., 2001; Lanés et al., 2012; Guedes et al., 2020). Preparation for reproduction can cause oxidative stress and affect maternal self-maintenance (Godoy et al., 2020) and consequently the somatic growth of females. Differences in body size mediate the coexistence of annual fish in temporary pools by mitigating intra and interspecific competition (Arenzon et al., 2001; Volcan et al., 2019). Therefore, intraspecific differences observed in body size between males and females may be associated with different reproductive energy costs, in addition to playing an important role in population coexistence.
A reduced batch fecundity (24.8 ± 8.8 eggs) was found for N. minimus, as well as for other annual species such as Cynopoecilus melanotaenia (Regan, 1912) (19 ± 26 eggs; Gonçalves et al., 2011), Austrolebias nigrofasciatus Costa & Cheffe, 2001 (21.5 ± 12 eggs; Volcan et al., 2011), and Leptopanchax opalescens (Myers, 1942) (27 ± 7.0 eggs; Guedes et al., 2023). However, the eggs are relatively large (maximum 1.006 μm) when weighted by the spatial limitations imposed by the coelomic cavity in this species of reduced body size (< 4 cm). According to the optimal egg size theory, populations evolve a particular egg size that balances the tradeoff between egg size and fecundity to maximize reproductive yield (Smith, Fretwell, 1974). Therefore, larger eggs come at a cost of reducing the number of eggs, which is in accordance with the findings of this study. Annual species have smaller eggs when compared to non-annual species of the family Rivulidae (Guedes et al., 2023). This may be associated with the extreme tolerance of embryos to hypoxia due to the process of embryonic diapause, which culminates in developmental arrest, metabolic depression, and G1 cell cycle arrest (Podrabsky et al., 2016). For species without embryonic diapause, the optimal investment in offspring size increases as environmental quality decreases (Rollinson, Hutchings, 2013; Riesch et al., 2014; Santi et al., 2021). The zona pellucida of mature eggs of N. minimus featured mushroom-like projections similar to other species in the genera Leptopanchax and Notholebias (Costa, Leal, 2009; Thompson et al., 2017). Wourms, Sheldon (1976) hypothesized that these projections are a chorionic respiratory system since there is a network of channels leading to hollow spikes that may function as egg-like aeropiles, similar to insect eggs. This may be an adaptation for annual fishes since a thick, hard, and consequently poorly oxygen-permeable zona pellucida may be necessary to prevent desiccation (Thompson et al., 2017).
Notholebias minimus is currently found in five conservation units in the State of Rio de Janeiro, including the unpublished record in the Brisas APA presented here. However, other species such as Notholebias vermiculatus and N. fractifasciatus do not occur in protected areas (ICMBio, 2018). Notholebias cruzi whose type locality is outside a conservation unit, had its biotopes destroyed due to urban expansion and has not been found since 2002, and may be extinct (Costa, 2012; Lira, 2021). Biotopes of N. minimus located inside conservation units show great natural cover and environmental restoration trends between 1985 and 2021. On the other hand, locations without any protection show greater coverage of anthropic matrices (pasture, urban area) and a loss of temporary wetlands between 1985 and 2021. These results show the important role played by protected areas in the conservation of biotopes. However, even the protected areas showed high coverage (52%) of anthropic matrices, which may reflect the type of territorial policy, since part of these units are for sustainable use and consequently have fewer restrictions on land use (SNUC, 2000), and/or historical deforestation prior to 1985, since the Brazilian Atlantic Forest biome is historically impacted (Joly et al., 2014; Egler et al., 2020).
The wide geographic distribution of N. minimus, combined with records in conservation units, places this species in a more favorable conservation position when compared to other species of the genus Notholebias. Our findings reveal that biotopes located within protected areas show a trend of restoration between 1985–2021, with an advancement of natural matrices. Conversely, biotopes found in unprotected areas show an opposite trend, with an increase in anthropogenic impacts on land use and coverage. However, it is crucial to maintain continuous monitoring of the biotopes, both inside and outside protected areas, to ensure the successful preservation of these endangered fish. In conclusion, our findings expand the knowledge of the habitats and population structure of N. minimus, and reinforce the importance of establishing protected areas for the conservation and restoration of annual fish biotopes.
ACKNOWLEDGEMENTSThis research was funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq (Proc. #140512/2022–5; 305712/2020–9; 306792/2021–4), Fundação Carlos Chagas Filho de Amparo à Pesquisa no Estado do Rio de Janeiro – FAPERJ (Proc. E–26/200.897/2021; E–26/202.483/2021), Fundo Brasileiro para a Biodiversidade – FUNBIO Conservando o Futuro, and Instituto HUMANIZE (Proc. # 028/2023). Special thanks to Yuri Borba for photographing the fish and habitat at Área de Proteção Ambiental das Brisas.
REFERENCES
Astyanax apiaka • A New Species of Astyanax (Characiformes: Characidae) from the rio Apiacás, rio Teles Pires Basin, Mato Grosso, BrazilBrazil
Astyanax apiaka
Ferreira, Lima, Ribeiro, Flausino, Machado & Mirande, 2023
DOI: 10.1139/cjz-2022-0153
Researchgate.net/publication/369917162
Abstract
A new species of Astyanax Baird & Girard, 1854 is described from the rio Apiacás, a tributary of the rio Teles Pires, rio Tapajós basin, Mato Grosso state, Brazil. The new taxon can be distinguished from all congeners, except those belonging to the Astyanax bimaculatus species group and to the Astyanax orthodus species group, by the presence of a horizontally elongated to rounded humeral blotch. The new taxon can be readily distinguished from all species belonging to the A. bimaculatus species group and to the A. orthodus species group by presenting a distinct morphology in premaxillary and dentary teeth with conspicuous diastema (a teeth gap) between them. We also present a hypothesis about the phylogenetic relationships of the new taxon within Astyanax.
Key words: taxonomy, Stethaprioninae, Gymnocharacini, Astyanax apiaka, rio Tapajós basin, Neotropical region
Astyanax apiaka, uncatalogued specimen photographed alive during field work. Lateral view, left side.
Astyanax apiaka, sp. nov.
Etymology: The specific name honors the Apiaká, an indigenous group, which inhabits the region where the new species was collected, and also the eponymous river from where the species is endemic. A noun in apposition.
Rio Cabeça de Boi, a tributary of the rio Apiacás, rio Teles Pires basin, Brazil, type-locality of Astyanax apiaka.
Katiane M. Ferreira, Flávio C. T. Lima, Alexande C. Ribeiro, Nelson Flausino Jr., Francisco A. Machado and Juan Marcos Mirande. 2023. A New Species of Astyanax (Characiformes, Characidae) from the rio Apiacás, rio Teles Pires Basin, with a discussion on its phylogenetic position. Canadian Journal of Zoology. 101(2). DOI: 10.1139/cjz-2022-0153
Researchgate.net/publication/369917162_A_new_species_of_Astyanax_from_the_rio_Apiacas_rio_Teles_Pires_basin
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Astyanax apiaka
Ferreira, Lima, Ribeiro, Flausino, Machado & Mirande, 2023
DOI: 10.1139/cjz-2022-0153
Researchgate.net/publication/369917162
Abstract
A new species of Astyanax Baird & Girard, 1854 is described from the rio Apiacás, a tributary of the rio Teles Pires, rio Tapajós basin, Mato Grosso state, Brazil. The new taxon can be distinguished from all congeners, except those belonging to the Astyanax bimaculatus species group and to the Astyanax orthodus species group, by the presence of a horizontally elongated to rounded humeral blotch. The new taxon can be readily distinguished from all species belonging to the A. bimaculatus species group and to the A. orthodus species group by presenting a distinct morphology in premaxillary and dentary teeth with conspicuous diastema (a teeth gap) between them. We also present a hypothesis about the phylogenetic relationships of the new taxon within Astyanax.
Key words: taxonomy, Stethaprioninae, Gymnocharacini, Astyanax apiaka, rio Tapajós basin, Neotropical region
Astyanax apiaka, uncatalogued specimen photographed alive during field work. Lateral view, left side.
Astyanax apiaka, sp. nov.
Etymology: The specific name honors the Apiaká, an indigenous group, which inhabits the region where the new species was collected, and also the eponymous river from where the species is endemic. A noun in apposition.
Rio Cabeça de Boi, a tributary of the rio Apiacás, rio Teles Pires basin, Brazil, type-locality of Astyanax apiaka.
Katiane M. Ferreira, Flávio C. T. Lima, Alexande C. Ribeiro, Nelson Flausino Jr., Francisco A. Machado and Juan Marcos Mirande. 2023. A New Species of Astyanax (Characiformes, Characidae) from the rio Apiacás, rio Teles Pires Basin, with a discussion on its phylogenetic position. Canadian Journal of Zoology. 101(2). DOI: 10.1139/cjz-2022-0153
Researchgate.net/publication/369917162_A_new_species_of_Astyanax_from_the_rio_Apiacas_rio_Teles_Pires_basin
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Chiloglanis fortuitus
Chlioglanis frodobragginsi
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31 July 2023
Two New Species of Suckermouth Catfishes (Mochokidae: Chiloglanis) from Upper Guinean Forest Streams in West Africa
Ray C. Schmidt, Pedro H. N. Bragança, John P. Friel, Frank Pezold, Denis Tweddle, Henry L. Bart Jr.
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Ichthyology & Herpetology, 111(3):376-389 (2023). https://doi.org/10.1643/i2022067
AbstractSuckermouth catfishes of the genus Chiloglanis are found throughout tropical Africa. Recent studies highlighted the diversity within this genus remains incompletely documented and nearly 20 new species have been described in the past ten years. Here we describe two new species of Chiloglanis from streams in the Upper Guinean Forest. Chiloglanis fortuitus, new species, is only known from one specimen collected in the St. John River drainage in Liberia and is readily distinguished from other species of Chiloglanis by the number of mandibular teeth and the length of the barbels associated with the oral disc. Chiloglanis frodobagginsi, new species, from the upper Niger River was previously considered to be a disjunct population of C. micropogon. A combination of several characters diagnoses C. frodobagginsi, new species, from topotypic C. micropogon in the Lualaba River (Congo River basin) and from Central African populations of Chiloglanis cf. micropogon in the Benue, Ndian, and Cross River drainages. The biogeographical implications of the recognition of C. frodobagginsi, new species, the likelihood of finding additional diversity in the streams of the Upper Guinean Forests, and the taxonomy of C. micropogon and C. batesii are also discussed.
There are currently 63 species of suckermouth catfishes in the genus Chiloglanis (Mochokidae) generally associated with flowing waters throughout tropical Africa (Fricke et al., 2022). Several species were described in recent years (Friel and Vigliotta, 2011; Schmidt et al., 2015, 2017; Schmidt and Barrientos, 2019; Kashindye et al., 2021) and many more taxa remain to be formally described (Morris et al., 2016; Chakona et al., 2018; Watson, 2020; Ward, 2021). Though superficially similar in morphology, these species have many informative diagnostic characters associated with their teeth, oral disc morphology, barbels, and spine and fin-ray lengths. Thus, many species originally considered to be widely distributed can clearly be separated into different species by carefully examining these characters.
This research on the Upper Guinean species of Chiloglanis started by looking at the morphological and molecular variation within the previously reported widespread species Chiloglanis occidentalis in streams of the Upper Guinean Forest. A molecular analysis revealed the presence of distinct lineages/species within C. occidentalis, many of which were endemic to individual river basins (Schmidt et al., 2016). These species broadly formed two groups: one group with generally shorter dorsal spines, pectoral spines, and maxillary barbels, and the other with longer dorsal and pectoral spines, and longer maxillary barbels. Within the region, endemic species belonging to both groups co-occur (sympatry) in several drainages in southeastern Guinea, seemingly using different microhabitats. The same study also showed that populations of another species, C. aff. micropogon, in the upper Niger River drainage in Guinea were genetically distinct from topotypic populations of C. micropogon in the Lualaba River (Congo River drainage) with 3.6% divergence in cytochrome b and 6.2% divergence in growth hormone intron 2 (Schmidt et al., 2016). In another paper on the diversity of Chiloglanis in the Upper Guinean Forests, when examining and selecting the type series for C. tweddlei, one specimen clearly stood out morphologically (Schmidt et al., 2017). This specimen superficially resembled members of the group with shorter spines and barbels, but it had more mandibular teeth than any other species of Chiloglanis in the region.
The present study aimed to examine the morphological variation among populations of C. micropogon and C. aff. micropogon to determine if the populations in the upper Niger River deserved specific recognition. Further, the unique specimen collected in the St. John River drainage was reexamined and the presence of other specimens of this unique morphotype in ichthyological collections investigated. The results of this study support the recognition of these two populations as distinct species of Chiloglanis which are described herein: C. frodobagginsi, new species, from the upper Niger River previously identified as C. aff. micropogon, and C. fortuitus, new species, from the St. John River drainage. We also discuss the variation within populations of C. micropogon in Central Africa and highlight areas where further collection efforts are needed.
MATERIALS AND METHODSSpecimens of Chiloglanis and other taxa were collected during several expeditions in Guinea and Liberia. Three of these expeditions occurred during 2003, and the most recent collections took place in 2012 (Liberia) and 2013 (Guinea; Fig. 1). Specimens from these expeditions are cataloged at several institutions with the bulk of the material residing in AMNH, AUM, CUMV, SAIAB, and TU (acronyms according to Sabaj, 2020). Comparative material from the Lualaba River (type locality of C. micropogon) and populations of Chiloglanis cf. micropogon in the Benue River, Cross River, and Ndian River drainages were also included in the analysis. Measurements were taken to 0.1 mm with a digital caliper and a stereo microscope equipped with an ocular micrometer. Morphometric measurements and meristic counts follow Schmidt et al. (2017) modified from Skelton and White (1980) and Friel and Vigliotta (2011). The holotype of C. micropogon was examined during a previous study, but a full suite of measurements was not collected. Sex of type specimens was determined by external examination of genital papillae following Friel and Vigliotta (2011). Measurements collected from the unique specimen from the St. John River drainage were included with the measurements from the short-spine taxa obtained in a previous study (Schmidt et al., 2017). A principal component analysis (PCA) using the covariance matrix of log-transformed measurements and descriptive statistics was completed in MYSTAT (SYSTAT Software Inc.). Body shape variation within principal components strongly correlated to size for populations of C. micropogon (e.g., PC1) was assessed through reduced-major axis (RMA) regression lines in the SMATR package in R (Warton et al., 2006).
Fig. 1Localities of species of Chiloglanis discussed in this study. Rivers of the Upper Guinean Forests enlarged from outlined region in the inset map of West and Central Africa. River drainages outlined in white lines. White circles are localities where no Chiloglanis were collected. Locations of Chiloglanis frodobagginsi (black circles), holotype of C. frodobagginsi (black star), type locality of Chiloglanis fortuitus (black triangle), and comparative Chiloglanis micropogon and Chiloglanis cf. micropogon (black squares).
RESULTSMorphological comparisons of populations of Chiloglanis.--A PCA of 45 morphometric measurements of C. fortuitus, new species, and 113 specimens of short-spine taxa shows C. fortuitus, new species, as distinct from the other taxa in the region (Fig. 2). Premaxillary tooth length and the length of the maxillary, medial, and lateral mandibular barbels contribute to the variation observed in PC2. These barbels are longer in C. fortuitus, new species, than in the other short-spine taxa, although with just one specimen of C. fortuitus, new species, it isn't possible to investigate these characters further.
Fig. 2Plots of PC1 to PC2 (A) and PC2 to PC3 (B) from principal component analysis of 45 log-transformed measurements from 114 specimens of the short-spine taxa from the Upper Guinean Forests. Holotype of Chiloglanis fortuitus denoted by star.
The morphological comparison of C. frodobagginsi, new species, and C. micropogon included 35 measurements and eight meristics from 50 specimens. Measurements shown to be sexually dimorphic (e.g., fin lengths and length of postcleithral process) were not included in the analysis (Supplemental Table A; see Data Accessibility). Plots of principal components 1 and 2 clearly separate C. frodobagginsi, new species, from C. micropogon in the Lualaba River (Fig. 3A). Populations of Chiloglanis cf. micropogon from the Benue, Ndian, and Cross River drainages are also distinct from topotypic C. micropogon and C. frodobagginsi, new species. Occipital shield width, mandibular tooth row width, maxillary barbel length, and distance between dorsal and adipose fins contribute to variation observed in PC2 (Supplemental Table B; see Data Accessibility). In plots of PC2 to PC3, populations of C. micropogon from the Lualaba River and C. frodobagginsi, new species, are still distinct (Fig. 3B). The populations in the Moa River are also largely distinct from Niger River C. frodobagginsi, new species (Fig. 3A, B). These two specimens are only 19.4 and 20.1 mm SL so additional specimens from this population are needed to better understand the variation observed.
Fig. 3Plots of PC1 to PC2 from principal component analysis of 35 log-transformed measurements from 47 specimens (A) and PC2 to PC3 (B). The holotype of Chiloglanis frodobagginsi is noted by the black star. Refer to Supplemental Table B (see Data Accessibility) for component loading values.
The first principal component was positively correlated with standard length (Pearson's correlation = 0.99). The RMA regression of PC1 to the log-transformed standard length (not shown) shows that the slopes of populations of Chiloglanis cf. micropogon, C. micropogon, and C. frodobagginsi, new species, are equal (P = 0.14) and that there is no difference in the elevation (i.e., the y-intercept) for each group (P = 0.39). When examining just the population of C. micropogon and C. frodobagginsi, new species, there is a difference in the elevation between the two (P = 0.04). Examining individual measurements and counts does give a sense of how the allometric trajectory of some of these traits differ in C. frodobagginsi, new species, and C. micropogon (Supplemental Fig. A; see Data Accessibility). The distance between the dorsal fin and adipose fin as a percentage of standard length has equal slopes (P = 0.164), but they have significantly different elevations (P = 0.0036; Fig. 4A). The number of premaxillary teeth plotted against log-transformed standard length for each species also clearly shows that these two species are distinct (Fig. 4B).
Fig. 4Reduced-major axis regression of distance from dorsal fin to adipose fin (as a percentage of standard length) on log-transformed standard length (A). Reduced-major axis regression of log-transformed total number of premaxillary teeth on log-transformed standard length (B). Chiloglanis frodobagginsi (open circle), Chiloglanis frodobagginsi from the Moa River (filled circle), Chiloglanis micropogon (open square), and holotype of C. frodobagginsi (black star).
Chiloglanis fortuitus, Schmidt, Bragança, and Tweddle, new species
urn:lsid:zoobank.org:act:5DAB9826-ADEE-42B5-84A8-934D5CCF4511
Figure 5, Table 1
- Holotype.--SAIAB 202292, 35.0 mm SL, Liberia, St. John River drainage, Nimba County, Dayea River, above Yekepa, 7.579333°N, 8.516889°W, D. Tweddle, 30 March 2012. Diagnosis.--Chiloglanis fortuitus is distinguished from all known species of Chiloglanis, including all species in the Upper Guinean Forest, except C. disneyi, C. microps, C. niger, and C. orthodontus, in having 18 mandibular teeth in the functional row (vs. 6–15 teeth; Table 1). Chiloglanis fortuitus is easily distinguished from C. disneyi, C. microps, and C. niger in having longer mandibular barbels whereas these are absent or reduced in the latter species. Chiloglanis fortuitus is distinguished from C. orthodontus in having a more robust oral disc and its length equal to its width versus length much shorter than width (Friel and Vigliotta, 2011). Chiloglanis fortuitus is further distinguished from C. orthodontus in having a longer dorsal spine (12.8 versus 4.1–7.8 % SL) and shorter maxillary barbels (7.2 versus 9.4–14.8 % SL).
- Description.--Morphometric measurements and meristics for holotype summarized in Table 1. Dorsal, lateral, and ventral views (Fig. 5) illustrate body shape, fin shape and placement, oral disc size and shape, and maxillary and mandibular barbel lengths.
- Moderate-sized Chiloglanis, maximum standard length observed 35.0 mm in one male specimen. Body dorsally depressed anteriorly and laterally compressed posteriorly. Pre-dorsal convex, sloping ventrally towards posterior nares, pre-orbital convex. Post-dorsal body sloping ventrally towards caudal fin. Post-anal profile concave, pre-anal profile horizontal. Small unculiferous tubercles present on body, concentrations of tubercles higher near head. Lateral line complete, arising at level of orbit and sloping ventrally to midlateral alongside of body towards caudal peduncle. Urogenital papillae presumed sexually dimorphic; males with elongated urogenital papilla.
- Head depressed. Gill membranes broadly united. Gill openings restricted, opening near pectoral-fin origin to horizontal level of orbit. Occipital-nuchal shield covered and visible through skin. Eye moderate in size, located post mid-head length, horizontal axis longest, without free margins. Anterior and posterior nares equidistant, positioned mid-snout. Naris with raised rims, posterior naris with elongated anterior flap.
- Mouth inferior, upper and lower lips united to form oral disc. Oral disc moderate in size, length equaling width and covered in papillae. Barbels in three pairs; maxillary barbel originating from posterolateral region of disc, unbranched, moderate in length, 7% of SL. Lateral and medial mandibular barbels moderate, incorporated into lower lip and positioned on both sides of midline cleft on posterior margin of oral disc. Lateral barbel 5% of SL, less than twice length of medial barbel. Primary maxillary teeth “S” shaped with exposed brown tips. 72 teeth in four scattered rows on ovoid tooth pads. Secondary premaxillary teeth scattered on posterior surface of premaxillae. Tertiary teeth small and needle-like, near midline of dorsal edge of tooth plate. Mandibular teeth in one to two rows, “S” shaped and grouped near midline. Functional (anterior) row with 18 brown-tipped teeth.
- Dorsal-fin origin just posterior to anterior third of body. Dorsal fin with small spinelet, spine, and four rays. Dorsal spine moderate to short in length, reaching 13% of SL. Adipose fin medium length, reaching 17% of SL; margin convex with small notch posteriorly. Caudal fin forked with rounded lobes, lower lobe longer than upper lobe, count i, 7, 8, i. Anal-fin origin posterior to origin of adipose fin, margin convex, count iii, 6. Pelvic-fin origin at vertical between dorsal and adipose fins, margin convex, reaching beyond anal-fin origin, count i, 6. Pectoral fin with smooth spine, reaching 16% of SL, count I, 7. Postcleithral process in holotype short and pointed.
- Coloration.--Coloration of preserved specimen in Figure 5. In dorsal view, dark brown with mottled areas of medium brown. Lighter areas between nares and orbits, at origin of dorsal fin, at origin and terminus of adipose fin, and at caudal peduncle. In lateral view, specimen with yellow-buff color with overlying medium and dark brown blotches. Dark area more prevalent dorsal to midline, extending ventrally at origins of pelvic and anal fins. Dark brown melanophores scattered across body, more readily visible ventral to midline, prominent on sides of belly. Ventral surface yellow-buff colored with few melanophores scattered near pelvic and anal fins. Oral disc and barbels cream colored.
- Pectoral and dorsal spines pigmented distally, rays cream to translucent. Dorsal base of pectoral fin lightly marked by triangular area of dark brown melanophores, band of melanophores at mid-length. Dorsal fin with area of melanophores near base and mid-length. Anal fin with melanophores at base and mid-length. Pelvic fin cream with few melanophores at base and band at mid-length. Adipose fin cream to translucent with dark brown markings from region just posterior of origin to its posterior third. Caudal fin cream to translucent with dark brown areas near base, mid-length, and distal end on upper and lower lobes; lighter areas forming circular marking on upper and lower lobes.
- Etymology.--The specific epithet is “fortuitus,” referring to the fortuitous aspect of collecting this one specimen at the type locality. The collector, D. Tweddle, sampled fishes at 36 localities in the upper St. John River drainage in Liberia and collected 69 specimens of Chiloglanis at ten of these localities. Additionally, the lot that contained C. fortuitus was one of the three lots borrowed by the lead author to aid with the description of C. tweddlei (Schmidt et al., 2017). The discovery and formal description of C. fortuitus is fortuitous in several aspects.
- Distribution.--Chiloglanis fortuitus is only known from the type locality in the Dayea River above Yekepa in Nimba County, Liberia (Supplemental Fig. B; see Data Accessibility). The site looked natural, yet it had been severely impacted many years earlier by the iron ore mine upstream. It was fast flowing, of uniform depth with a bottom of gravel with small rocks, with very little natural structure (e.g., woody debris and large boulders) likely due to previous mining activities. It is interesting that this species was not collected at the other ten localities in the region that contained C. tweddlei. As with other members of Chiloglanis that are found in streams in the Upper Guinea Forests, when two species co-occur within a drainage, they usually utilize different microhabitats (Schmidt et al., 2017). Additional collection efforts in the upper St. John River drainage in Guinea and Liberia may yield additional specimens and populations of C. fortuitus.
- Remarks.--Species descriptions based on a single specimen are not ideal though in this case it is warranted. This species is morphologically distinct from congeners in the region (Fig. 2), and the number of mandibular teeth and morphology of the oral disc and barbels, characters used in the taxonomy of species of Chiloglanis, clearly separate it from all other known species of Chiloglanis. In sampling fishes at 36 localities, the collector was only able to get one specimen of C. fortuitus. Another lot from the St. John River drainage, USNM 193949, collected in the 1950s, contained 17 specimens all of which were determined to be C. tweddlei. This species is seemingly rare within the drainage and we don't know when, or even if, additional specimens of C. fortuitus will be collected. Additionally, this area is under intense pressures from the mining industry and all species present face an uncertain future. Indeed, the type specimen was collected in a stream that had previously been disturbed by iron ore mining. Formally describing this species is an important step in recognizing and conserving the freshwater biodiversity in the Upper Guinean Forests.
- Chiloglanis fortuitus resembles species of Chiloglanis that are in the short-spine group referenced in Schmidt et al. (2016, 2017). The discovery of this new species within the St. John River suggests that additional species of Chiloglanis, and other taxa, remain to be discovered and described from the region. This is especially likely for rivers in the region (e.g., Rokel, Jong, Sewa, and Mano) where collections of freshwater taxa are still lacking. While collecting this specimen was fortuitous, depositing the specimen and the others collected during an environmental impact assessment into natural history collections is what allowed this species to be discovered and described. Other new species have been collected and formerly described from similar surveys in the region (Pezold et al., 2016, 2020). We encourage practitioners in this field to continue the practice of depositing specimens collected during assessments in natural history collections so that the specimens will be available to researchers.
Table 1Morphometric measurements and meristics for holotype of Chiloglanis fortuitus. Standard length expressed in mm. All other measurements expressed in percent SL.
Chiloglanis frodobagginsi, Schmidt, Friel, Bart, and Pezold, new species
urn:lsid:zoobank.org:act:02157426-E35A-4ABB-BEF4-85047A68B5C8
Figure 6, Table 2
- Chiloglanis batesii.--Paugy and Roberts, 1992 (in part): 502–511; Paugy and Roberts, 2003 (in part): 197–207.
- Chiloglanis micropogon.--Daget, 1954 (in part): 307–308; Daget, 1959 (in part): 682–683; Daget, 1962 (in part): 115.
- Chiloglanis cf. micropogon.--Schmidt et al., 2016: 201–204.
- Chiloglanis sp. aff. micropogon.--Schmidt et al., 2017: 301–336.
- Holotype.--TU 203552, 24.1 mm SL, Guinea, Niger River, North of Faranah, on road N29, 10.28382°N, 10.76925°W, 2013 Guinea expedition team, 29 January 2013.
- Paratypes.--AMNH 263794, 4, 23.1–25.7 mm SL, AUM 59751, 8, CUMV 97679, 8, TU 203527, 4, 24.8–25.3 mm SL, Guinea, Niger River drainage, Mafou River, on road N2 ∼80 km South of Faranah, 9.53072°N, 10.40199°W, 2013 Guinea expedition team, 28 January 2013; AUM 59554, 19, CUMV 97678, 18, TU 203348, 19, 20.6–24.1 mm SL, FLMNH 249106, 5, 20.0–24.6 mm SL, Guinea, Niger River drainage, Tinkisso River, below Tinkisso Dam, 10.72793°N, 11.16855°W, 2013 Guinea expedition team, 12 January 2013; CUMV 97680, 6, TU 204171, 4, 19.2–24.3 mm SL, collected with holotype; SAIAB 203746, 9, 19.9–23.3 mm SL, USNM 437542, 9, 22.1–38.1 mm SL, Niger River drainage, Tinkisso River, at dam, 10.72°N 11.17°W, B. Samoura and others, 7 April 2003; TU 204157, 1, 20.4 mm SL, Guinea, Niger River drainage, Tinkisso River, at dam, 10.72793°N 11.16855°W, F. Pezold and others, 18 January 2003.
- Non-type material examined.--AMNH 264623, 1, 26.3 mm SL, Guinea, Niger River drainage, Tinkisso River, at Toumania, 10.57902°N, 10.47273°W, F. Pezold and others, 16 May 2003; CUMV 98653, 1, 19.4 mm SL, TU 204170, 1, 20.1 mm SL, Guinea, Moa River drainage, Masseni River, about 3 miles north of Konesseridou, 8.7204°N, 9.52436°W, 2013 Guinea expedition team, 26 January 2013; MRAC 2016.029.P.52-63, 12, 20.0–27.0 mm SL, Guinea, Niger River drainage, Tinkisso River, at Bissikrima, 10.83°N, 10.92°W, B. Samoura and others, 8 April 2003; USNM 437545, 5, 22.2–23.5 mm SL, Guinea, Niger River drainage, Niger River, north of Faranah, F. Pezold and others, 26 May 2003.
- Diagnosis.--Chiloglanis frodobagginsi is distinguished from all known species of Chiloglanis in the Upper Guinean Forests, and most of the other described species (except C. disneyi, C. harbinger, C. marlieri, C. micropogon, C. microps, C. mongoensis, and C. niger) by the very reduced, or absent, mandibular barbels on the oral disc. Chiloglanis frodobagginsi can be distinguished from C. disneyi, C. harbinger, C. marlieri, C. microps, C. mongoensis, and C. niger in having fewer mandibular teeth in one row (10–12 versus 16–20, 26–30, 26–28, 16–18, 28, and 16–20 respectively). Chiloglanis frodobagginsi is distinguished from C. batesii in having two prominent papillae on the roof of the oral cavity; versus the absence of papillae in C. batesii. This species is further distinguished from C. batesii in having shorter and more blunt mandibular teeth arranged in bunched rows; versus sharper, more elongate, and disordered mandibular teeth. Chiloglanis frodobagginsi also has a fleshy unpapillated ridge posterior to the mandibular teeth versus several large papillae in C. batesii (Friel and Vigliotta, 2011).
- A unique combination of characters distinguishes C. frodobagginsi from the closely related C. micropogon and C. cf. micropogon from Central Africa. As compared to C. micropogon from the Lualaba River, C. frodobagginsi has a larger eye diameter (4.2–6.5 versus 4.7–5.5 % SL; Supplemental Fig. A; see Data Accessibility), longer maxillary barbels (3.8–7.2 versus 3.4–6.5 % SL; Supplemental Fig. A; see Data Accessibility), a narrower mandibular tooth row (1.6–2.8 versus 2.4–3.1 % SL; Supplemental Fig. A; see Data Accessibility), a longer distance between dorsal fin and adipose fin (14.4–21.5 versus 14.9–18.8 % SL; Fig. 4A), and a shorter anal-fin base length (8.0–10.8 versus 9.7–12.7 % SL; Supplemental Fig. A; see Data Accessibility). Chiloglanis frodobagginsi is further distinguished from C. micropogon in having fewer premaxillary teeth (36–70 versus 62–103) scattered in three rows versus four (Fig. 4B; Table 2). While the ranges of these measurements and counts overlap, these distinctions hold true when comparing similar sized species (Fig. 4; Supplemental Fig. A; see Data Accessibility). Compared to Chiloglanis cf. micropogon from the Benue, Ndian, and Cross River basins Chiloglanis frodobagginsi has a narrower occipital shield (3.0–4.0 versus 4.0–5.4 % SL), a shorter dorsal fin to adipose fin distance (14.5–21.5 versus 19.3–24.2), and a narrower mandibular tooth row (1.6–2.8 versus 1.8–3.2 % SL).
- Description.--Morphometric measurements and meristics for holotype and 21 paratypes summarized in Table 2. Dorsal, lateral, and ventral views (Fig. 6) illustrate body shape, fin shape and placement, oral disc size and shape, and maxillary and mandibular barbel lengths.
- Small to moderate-sized Chiloglanis, maximum standard length 38.1 mm. Body dorsally depressed anteriorly and laterally compressed posteriorly. Pre-dorsal convex, sloping ventrally towards posterior nares, pre-orbital convex, sharply angling towards tip of snout pre-nares. Post-dorsal body sloping ventrally towards caudal fin. Post-anal profile shallowly concave, pre-anal profile horizontal to slightly convex. Small unculiferous tubercles present on body, concentrations of tubercles higher near head. Lateral line complete, arising at dorsal level of orbit and sloping ventrally to midlateral alongside of body towards caudal peduncle. Urogenital papillae sexually dimorphic; males with elongated urogenital papillae, females with reduced papillae, separated from anus by shallow invagination.
- Head depressed. Gill membranes broadly united. Gill openings restricted, opening near pectoral-fin origin to horizontal level of mid-orbit. Occipital-nuchal shield covered and visible through skin. Eye moderate in size, located post mid-head length, horizontal axis longest, without free margins. Anterior naris set farther apart than posterior naris, positioned mid-snout. Nares with raised rims, posterior naris with elongated anterior flap.
- Mouth inferior, upper and lower lips united to form oral disc. Oral disc moderate in size, slightly wider than long and covered in papillae. Maxillary barbel originating from posterolateral region of disc, unbranched, moderate in length, reaching 7% of SL. Lateral and medial mandibular barbels absent or very reduced. Two prominent papillae on roof of oral cavity. Primary maxillary teeth “S” shaped with exposed brown tips. 36–70 teeth in three scattered rows on ovoid tooth pads. Secondary premaxillary teeth scattered on posterior surface of premaxillae. Tertiary teeth small and needle-like, near midline of dorsal edge of toothplate. Mandibular teeth in one to two rows, curved and bunched near midline. Functional (anterior) row with 12 brown-tipped teeth. Distinct, slightly concave rectangular fleshy ridge posterior to mandibular teeth.
- Dorsal-fin origin just posterior to anterior third of body. Dorsal fin with small spinelet, spine, and five to six rays. Dorsal spine medium to short in length, reaching 13% of SL. Adipose fin medium length, reaching 19.6% of SL; margin convex. Caudal fin forked with rounded lobes, lower lobe longer than upper lobe, count i, 7, 8, i, no sexual dimorphism observed in examined specimens. Anal-fin origin posterior to origin of adipose fin, margin convex, count iii, 5–7. Pelvic-fin origin at vertical between dorsal and adipose fin, margins convex, reaching beyond anal-fin origin, count i, 6. Pectoral fin with smooth spine, reaching 15.6% of SL, count I, 8–9. Postcleithral process shorter and bluntly pointed, no sexual dimorphism noted in specimens examined.
- Coloration.--Typical coloration of preserved specimens in Figure 6. In dorsal view, specimens medium brown with mottled areas of light brown. Lighter areas on tip of snout anterior to nares, at origin of dorsal fin, at origin and terminus of adipose fin, and on caudal peduncle. White or cream unculiferous tubercles scattered across body, more concentrated near head. In lateral view, specimens with yellow-buff color with overlying medium brown blotches. Dark area more prevalent dorsal to midline, but extending ventrally at origin of pelvic and anal fins. Dark brown melanophores scattered across body, more readily visible ventral to midline, absent on belly. Ventral surface yellow-buff colored with few melanophores scattered near anus and origin of anal fin. Oral disc and barbels cream colored.
- Pectoral and dorsal spines pigmented distally and rays cream to translucent. Dorsal base of pectoral fin lightly marked by triangular area of dark brown melanophores, band of melanophores at mid-length. Dorsal fin with area of melanophores near base and mid-length. Anal fin with melanophores at mid-length. Pelvic fin cream with few melanophores at base and band at mid-length. Adipose fin cream to translucent with dark brown markings at origin. Caudal fin cream to translucent with dark brown areas near base and at mid-length.
- Etymology.--Chiloglanis frodobagginsi is named after another diminutive traveler, Frodo Baggins, a fictional character well known from J. R. R. Tolkien's The Lord of the Rings series. Roughly 3,000 miles (4,800 km) separate C. frodobagginsi in the upper Niger River drainage and C. micropogon, the sister species, found in the Congo River basin. Another seemingly closely related species, Chiloglanis cf. micropogon, is found in the southern Benue drainage and in several small coastal rivers about 3,000 km from the upper Niger River drainage (e.g., Cross and Ndian Rivers). It is unclear whether these species are descended from a more widespread species, or the result of dispersal from the Congo River basin into the Niger River drainage, via the Benue River, and then up to the headwaters of the Niger River. This was an incredible journey for such a small and seemingly non-vagile fish.
- Distribution.--Chiloglanis frodobagginsi occurs in the upper Niger River drainage in Guinea and further downstream in the Niger River near Bamako (Fig. 1; Daget, 1959). This species was collected in several tributaries to the Niger River in Guinea and also collected in the upper reaches of the Moa River drainage (Masseni River), a coastal river drainage. Only two specimens were collected in the Moa River drainage and no tissues were retained. Given that most species of Chiloglanis in the region are restricted to individual river drainages and since the Moa River drainage is on the other (i.e., west) side of the Guinean Range from the Niger River drainage, this population may be a distinct species. For this reason, these specimens were not included in the type material for C. frodobagginsi. In the Tinkisso River, C. frodobagginsi was collected below the waterfall over small gravel in the middle of the channel. Chiloglanis waterloti is also found in the Tinkisso River, but this species is usually associated with woody debris or large rocks.
- Remarks.--The affinity between Chiloglanis frodobagginsi and C. micropogon was first reported in research on fishes in the upper Niger River drainage (Daget, 1954, 1959). The large distance between the populations in the upper Niger River and the Lualaba River (Congo River drainage) warranted further examinations of these specimens (Daget, 1959). Daget sent specimens from the upper Niger River to Max Poll for comparison to those that Poll described as C. micropogon from the Congo River drainage (Poll, 1952; Daget, 1959). Poll noted some variation between the different populations, but it wasn't enough to readily distinguish one from the other (Daget, 1959). Daget also noted their diminutive size and rarity relative to the co-occurring specimens of C. waterloti (Daget, 1954). Herein we noted another aspect of these specimens that wasn't directly noted: the apparent lack of an elongated upper caudal-fin lobe and an elongate and spatulate postcleithral process in males. An examination of the type specimen of C. micropogon and the sketch of the holotype clearly shows an elongated upper caudal-fin lobe (Poll, 1952, fig. 3, page 228). The larger specimens collected in recent expeditions were mostly females, and none of the males collected showed an elongated upper caudal-fin lobe. More specimens of C. frodobagginsi are needed to better understand if this species also displays those sexually dimorphic characteristics, or if the lack of sexual differentiation can be a useful trait in distinguishing both species. Chiloglanis frodobagginsi is also genetically distinct from C. micropogon with a divergence observed of 3.6% in cytochrome b and 6.2% in Growth Hormone intron 2 (Schmidt et al., 2016).
- Populations of Chiloglanis cf. micropogon in the Benue, Cross, and Ndian Rivers have only been relatively recently collected (e.g., in the 1970s and 1980s) and were unknown to Daget and Poll at the time of their comparisons of upper Niger and Lualaba River specimens. In examining these specimens, they clearly concur with C. micropogon, but also differ in some respects (Fig. 3). Some specimens showed the sexual dimorphism attributed to C. micropogon (e.g., an elongated upper caudal-fin lobe and an elongated and spatulate postcleithral process), but most of the specimens examined did not have these traits. Many of these collections and subsequent identifications took place before many of the species in the region were described (Roberts, 1989) and cataloged under superficially similar species names C. niger and C. disneyi. Additional populations from the Benue and the smaller coastal drainages in Central Africa are needed to fully resolve the relationships within the C. micropogon complex.
Table 2Morphometric measurements and meristics for Chiloglanis frodobagginsi (n = 22; holotype and 21 paratypes) and topotypic Chiloglanis micropogon (n = 10). Standard length expressed in mm. All other measurements expressed in percent SL. Meristic data for holotype are identified by an asterisk (*).
DISCUSSIONThe two new species of Chiloglanis described herein provide further evidence that the Upper Guinean Forests support a wealth of biodiversity. Chiloglanis fortuitus was collected during an environmental assessment in the upper St. John River drainage in Liberia. This one specimen was serendipitously borrowed when examining type material for the description of the co-occurring C. tweddlei. The presence of multiple species within these forested streams suggests many more species remain to be discovered and formally described. Many of the streams that originate on the western slope of the Guinean Range remain relatively unexplored. As anthropogenic pressures increase in the region, it is critical that these rivers are surveyed so that this biodiversity can be documented before it is lost (Lalèyè et al., 2021).
Chiloglanis micropogon was, until recently, considered a synonym of Chiloglanis batesii (Roberts, 1989; Friel and Vigliotta, 2011). Roberts considered C. batesii to be one of the most widespread species of Chiloglanis occurring from the upper Niger River drainage to the Congo River basin, and throughout Central Africa (Roberts, 1989). Friel and Vigliotta (2011) recognized C. micropogon as a distinct taxon based on several different characters. Papillae on the roof of the oral cavity are present in C. micropogon but absent in C. batesii. These papillae are also present in the holotype of C. frodobagginsi (Fig. 6). There were also several oral disc characters mentioned (e.g., fleshy ridge posterior to mandibular teeth) that distinguished C. micropogon and C. batesii (Friel and Vigliotta, 2011). Chiloglanis batesii was likely described from Nyong River drainage in southern Cameroon (Boulenger, 1904). Populations of Chiloglanis, reported as C. batesii or C. micropogon, from the Nyong River to the Niger River need to be examined in more detail to determine the distributions of these species. Populations of Chiloglanis cf. micropogon from the Benue, Ndian, and Cross River basins appear to be distinct from topotypic C. micropogon, but additional specimens are needed from the region for confirmation (Fig. 3; Supplemental Table C; see Data Accessibility).
Understanding the diversity of Chiloglanis in the region is complicated by the presence of several species that are superficially similar to C. micropogon and C. batesii, especially smaller individuals. Chiloglanis niger also has reduced/absent mandibular barbels and around 12 mandibular teeth. The smaller individuals examined are very similar to C. micropogon, but are readily distinguished by the straight, robust mandibular teeth and smaller eye, relative to similar-sized C. micropogon. Small specimens of C. disneyi can also superficially resemble C. micropogon, but this species usually has many more mandibular teeth (16–20 versus 12) and has small mandibular barbels. Most of these species were described around the same time as several major collecting expeditions in the region (Teugels et al., 1992), and many of the specimens were deposited as Chiloglanis sp. or incorrectly placed into one of the newly described species. Sexual dimorphism in these species is also seemingly variable. One smaller male specimen of C. cf. micropogon from the Benue River clearly has an elongate and spatulate postcleithral process and elongated upper caudal-fin lobe. Another specimen, determined to be C. niger, has an elongated upper caudal-fin lobe but not an elongate postcleithral process. Another issue is the relative lack of material from the region. Many lots only contain one or a few specimens and some of those are damaged. It seems that many of these fishes are relatively rare (but may be locally abundant) and are often not sampled if electrofishers are not utilized. Examining the remaining cataloged material from this region should clarify some of these issues, but additional collecting in Cameroon and surrounding areas is also needed.
The biogeographical implications of the close relationship between the Upper Guinean Forest C. frodobagginsi and the Congolese C. micropogon are also quite interesting. A previous study (Schmidt et al., 2016) appears to offer the first molecular evidence of a recent connection between the fish fauna in the Congo River basin and the Niger River drainage. This past connection was hypothesized based on several presumptive shared taxa that occur within the Congo, Chad, and Niger River drainages (e.g., Campylomormyrus tamandua; Lévêque, 1997). Lévêque (1997) hypothesized that fishes from the Congo River first entered the Chad basin and then gained access to the Niger River drainage through the Gauthiot Falls in the upper Benue River. The presence of Chiloglanis cf. micropogon in the Benue River drainage also supports the hypothesis that this river served as a dispersal corridor for fishes in the region. These fishes could have then spread throughout the Niger River drainage, and subsequent climatic changes may have restricted them to well-watered regions within the watershed. The headwater streams of the Niger River drainage in Guinea have likely served as refugia where forests, and more importantly water, have persisted during climatic fluctuations (Mayr and O'Hara, 1986). Other fishes that are thought to occur within the Congo and Niger drainages should be investigated to see if similar patterns exist.
The presence of C. frodobagginsi in the upper Moa River also provides further evidence for headwater capture in the region. The diversity within these forested streams that arise along the Guinean Range has likely been fueled by recurring headwater capture events in the region. This would allow for species to geodisperse (vicariance) into neighboring drainages and diversify. If enough time passes before another headwater capture event, or the headwater capture event is across the Guinean Range versus alongside of it, a second or third species can become established in the system. In the Moa River system, there are three species of Chiloglanis, and within the Loffa and St. John River drainages there are two species present (Schmidt et al., 2017). These mechanisms that have probably promoted diversification within Chiloglanis have likely also promoted diversification within the mountain catfishes (Amphilius) and African small barbs (Enteromius; Schmidt and Pezold, 2011; Schmidt, 2014; Schmidt et al., 2019). Similarly, it seems that the diversity in other co-occurring groups of fishes is also vastly underestimated and needs to be investigated further.
MATERIAL EXAMINEDChiloglanis micropogon: Democratic Republic of the Congo: Congo River drainage: CUMV 97580, 10 of 101, 18.6–22.0 mm SL, Lualaba River, at main portion of Wagenia Falls, 0.49413°N, 25.20701°E; MRAC 91479, holotype, 49 mm SL, Nzokwe River, affluent of Ulindi River, Territory Kabare, 2.92°S, 28.53°E, G. Marlier, 20 May 1949.
Chiloglanis cf. micropogon: Nigeria: Benue River drainage: USNM 338276, 2, 21.3–28.0 mm SL, Mayo Santo (Fulani) or River Shuntan, small stream inflow to main river near Gashaka Camp. This eventually drains to the River Taraba which joins the River Benue, 7.3806°N, 11.4736°E. Cameroon: Cross River drainage: USNM 304265, 3, 22.4–26.3 mm SL, collecting points upper tributaries of Munaya, near Baro Village, northern Korup, Bake River below Nere Bifa Falls, 5.833°N, 9.1722°E; USNM 304331, 5, 22.3–36.3 mm SL, Akpa-Yafe System, streams and rivers of southwest Korup, Akpasang River at crossing point nearest end of ‘P’ (transect), 5.01°N, 8.75°E; Ndian River drainage: USNM 303409, 44, 25.7–27.4 mm SL, streams and rivers of southeast boundary of Korup, main Ndian River at bridge crossing into Korup, 4.9833°N, 8.85°E; USNM 303624, 1, 39.7 mm SL, streams and rivers of southeast boundary of Korup, Owaye River just north of Mana River, Korup ‘buffer zone A,’ 5.1°N, 8.9833°E.
Chiloglanis niger: Cameroon: Benue River drainage: USNM 280387, 1, 54.7 mm SL, Northwest Province, Fujua, fast flowing stream with rocky bottom, 6.28333°N, 10.28333°E (georeferenced); USNM 338335, 1, 38.9 mm SL, Mayo Dundere, the upper reaches of the Mayo Gashaka/Mayo Korngal. This eventually drains to the River Taraba which joins the River Benue, 7.0306°N, 11.5667°E; USNM 338717, 1, 41.7 mm SL, Mayo Katan, at the crossing point with a dirt road. This stream eventually drains to the River Taraba which joins the River Benue, 7.1639°N, 11.3917°E.
Chiloglanis tweddlei: Liberia: St. John River drainage: SAIAB 188313, 3, Nimba County, Kahn River upstream, 7.589167°N, 8.568611°W; SAIAB 188352, 1, Nimba County, Bold River, 7.50444°N, 8.58944°W; SAIAB 188448, 1, Nimba County, Yiti River, main road, 7.4875°N, 8.615278°W; SAIAB 188466, 3, Nimba County, Dehn River, at Lugbei, 7.608611°N, 8.622778°W; SAIAB 188551, 8, Nimba County, Yiti River, 7.516111°N, 8.704167°W; SAIAB 188582, 10, Nimba County, Yiti River upstream, 7.510278°N, 8.749167°W; SAIAB 188608, 1, Nimba County, Bee River, at Saniquellie, 7.369556°N, 8.697278°W; SAIAB 188639, 3, Nimba County, Tributary of Vellie River, 7.5755°N, 8.657722°W; USNM 193949, 17, Bong County, Gbarngy District, streams and tributary to St. John River.
DATA ACCESSIBILITYSupplemental material is available at https://www.ichthyologyandherpetology.org/i2022067. Unless an alternative copyright or statement noting that a figure is reprinted from a previous source is noted in a figure caption, the published images and illustrations in this article are licensed by the American Society of Ichthyologists and Herpetologists for use if the use includes a citation to the original source (American Society of Ichthyologists and Herpetologists, the DOI of the Ichthyology & Herpetology article, and any individual image credits listed in the figure caption) in accordance with the Creative Commons Attribution CC BY License. ZooBank publication urn:lsid:zoobank.org:pub: AA5998FE-9F91-46B2-AB49-B8EDE9B6E4DA.
ACKNOWLEDGMENTSFunding for the 2003 expeditions was provided from the Critical Ecosystem Partnership Fund administered by Conservation International, the HHMI/ULM Undergraduate Science Education Program, and by OISE 0080699 to FP. Funding for the 2013 expedition provided from the All Cypriniformes Species Inventory (ACSII, NSF DEB #1023403). We thank S. Diallo, B. Coulibaly (deceased), M. Diop, B. Samoura, B. Kaba, M. Camara, and members of the 2002–2003 ULM Guinea expeditions for assistance in the field. The 2013 expedition included J. W. Armbruster, H. L. Bart, S. Diallo, T. Diallo, J. P. Friel, M. M. Hayes, M. Magase, and M. Sou. Comparative material was generously provided by C. Dillman (CUMV) and D. Pitassy (USNM). J. Mann (TU) loaned and shipped the specimens of C. frodobagginsi to RCS so that this description could be completed, T. Vigliotta (AMNH) shared the images of the holotype of C. micropogon, and R. Robins (FLMNH) assisted in cataloging type material. Many thanks to the collections staff at SAIAB and USNM who provided PHNB and RCS with material while institutions had restricted access during the COVID-19 pandemic. Sandra Raredon (USNM) photographed the type material of C. frodobagginsi and generously worked during restricted conditions due to the pandemic.
© 2023 by the American Society of Ichthyologists and Herpetologists
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Ray C. Schmidt, Pedro H. N. Bragança, John P. Friel, Frank Pezold, Denis Tweddle, and Henry L. Bart Jr. "Two New Species of Suckermouth Catfishes (Mochokidae: Chiloglanis) from Upper Guinean Forest Streams in West Africa," Ichthyology & Herpetology 111(3), 376-389, (31 July 2023). https://doi.org/10.1643/i2022067
Received: 18 August 2022; Accepted: 1 May 2023; Published: 31 July 2023
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31 July 2023Two New Species of Suckermouth Catfishes (Mochokidae: Chiloglanis) from Upper Guinean Forest Streams in West Africa
Ray C. Schmidt, Pedro H. N. Bragança, John P. Friel, Frank Pezold, Denis Tweddle, Henry L. Bart Jr.
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Ichthyology & Herpetology, 111(3):376-389 (2023). https://doi.org/10.1643/i2022067
AbstractSuckermouth catfishes of the genus Chiloglanis are found throughout tropical Africa. Recent studies highlighted the diversity within this genus remains incompletely documented and nearly 20 new species have been described in the past ten years. Here we describe two new species of Chiloglanis from streams in the Upper Guinean Forest. Chiloglanis fortuitus, new species, is only known from one specimen collected in the St. John River drainage in Liberia and is readily distinguished from other species of Chiloglanis by the number of mandibular teeth and the length of the barbels associated with the oral disc. Chiloglanis frodobagginsi, new species, from the upper Niger River was previously considered to be a disjunct population of C. micropogon. A combination of several characters diagnoses C. frodobagginsi, new species, from topotypic C. micropogon in the Lualaba River (Congo River basin) and from Central African populations of Chiloglanis cf. micropogon in the Benue, Ndian, and Cross River drainages. The biogeographical implications of the recognition of C. frodobagginsi, new species, the likelihood of finding additional diversity in the streams of the Upper Guinean Forests, and the taxonomy of C. micropogon and C. batesii are also discussed.
There are currently 63 species of suckermouth catfishes in the genus Chiloglanis (Mochokidae) generally associated with flowing waters throughout tropical Africa (Fricke et al., 2022). Several species were described in recent years (Friel and Vigliotta, 2011; Schmidt et al., 2015, 2017; Schmidt and Barrientos, 2019; Kashindye et al., 2021) and many more taxa remain to be formally described (Morris et al., 2016; Chakona et al., 2018; Watson, 2020; Ward, 2021). Though superficially similar in morphology, these species have many informative diagnostic characters associated with their teeth, oral disc morphology, barbels, and spine and fin-ray lengths. Thus, many species originally considered to be widely distributed can clearly be separated into different species by carefully examining these characters.
This research on the Upper Guinean species of Chiloglanis started by looking at the morphological and molecular variation within the previously reported widespread species Chiloglanis occidentalis in streams of the Upper Guinean Forest. A molecular analysis revealed the presence of distinct lineages/species within C. occidentalis, many of which were endemic to individual river basins (Schmidt et al., 2016). These species broadly formed two groups: one group with generally shorter dorsal spines, pectoral spines, and maxillary barbels, and the other with longer dorsal and pectoral spines, and longer maxillary barbels. Within the region, endemic species belonging to both groups co-occur (sympatry) in several drainages in southeastern Guinea, seemingly using different microhabitats. The same study also showed that populations of another species, C. aff. micropogon, in the upper Niger River drainage in Guinea were genetically distinct from topotypic populations of C. micropogon in the Lualaba River (Congo River drainage) with 3.6% divergence in cytochrome b and 6.2% divergence in growth hormone intron 2 (Schmidt et al., 2016). In another paper on the diversity of Chiloglanis in the Upper Guinean Forests, when examining and selecting the type series for C. tweddlei, one specimen clearly stood out morphologically (Schmidt et al., 2017). This specimen superficially resembled members of the group with shorter spines and barbels, but it had more mandibular teeth than any other species of Chiloglanis in the region.
The present study aimed to examine the morphological variation among populations of C. micropogon and C. aff. micropogon to determine if the populations in the upper Niger River deserved specific recognition. Further, the unique specimen collected in the St. John River drainage was reexamined and the presence of other specimens of this unique morphotype in ichthyological collections investigated. The results of this study support the recognition of these two populations as distinct species of Chiloglanis which are described herein: C. frodobagginsi, new species, from the upper Niger River previously identified as C. aff. micropogon, and C. fortuitus, new species, from the St. John River drainage. We also discuss the variation within populations of C. micropogon in Central Africa and highlight areas where further collection efforts are needed.
MATERIALS AND METHODSSpecimens of Chiloglanis and other taxa were collected during several expeditions in Guinea and Liberia. Three of these expeditions occurred during 2003, and the most recent collections took place in 2012 (Liberia) and 2013 (Guinea; Fig. 1). Specimens from these expeditions are cataloged at several institutions with the bulk of the material residing in AMNH, AUM, CUMV, SAIAB, and TU (acronyms according to Sabaj, 2020). Comparative material from the Lualaba River (type locality of C. micropogon) and populations of Chiloglanis cf. micropogon in the Benue River, Cross River, and Ndian River drainages were also included in the analysis. Measurements were taken to 0.1 mm with a digital caliper and a stereo microscope equipped with an ocular micrometer. Morphometric measurements and meristic counts follow Schmidt et al. (2017) modified from Skelton and White (1980) and Friel and Vigliotta (2011). The holotype of C. micropogon was examined during a previous study, but a full suite of measurements was not collected. Sex of type specimens was determined by external examination of genital papillae following Friel and Vigliotta (2011). Measurements collected from the unique specimen from the St. John River drainage were included with the measurements from the short-spine taxa obtained in a previous study (Schmidt et al., 2017). A principal component analysis (PCA) using the covariance matrix of log-transformed measurements and descriptive statistics was completed in MYSTAT (SYSTAT Software Inc.). Body shape variation within principal components strongly correlated to size for populations of C. micropogon (e.g., PC1) was assessed through reduced-major axis (RMA) regression lines in the SMATR package in R (Warton et al., 2006).
Fig. 1Localities of species of Chiloglanis discussed in this study. Rivers of the Upper Guinean Forests enlarged from outlined region in the inset map of West and Central Africa. River drainages outlined in white lines. White circles are localities where no Chiloglanis were collected. Locations of Chiloglanis frodobagginsi (black circles), holotype of C. frodobagginsi (black star), type locality of Chiloglanis fortuitus (black triangle), and comparative Chiloglanis micropogon and Chiloglanis cf. micropogon (black squares).
RESULTSMorphological comparisons of populations of Chiloglanis.--A PCA of 45 morphometric measurements of C. fortuitus, new species, and 113 specimens of short-spine taxa shows C. fortuitus, new species, as distinct from the other taxa in the region (Fig. 2). Premaxillary tooth length and the length of the maxillary, medial, and lateral mandibular barbels contribute to the variation observed in PC2. These barbels are longer in C. fortuitus, new species, than in the other short-spine taxa, although with just one specimen of C. fortuitus, new species, it isn't possible to investigate these characters further.
Fig. 2Plots of PC1 to PC2 (A) and PC2 to PC3 (B) from principal component analysis of 45 log-transformed measurements from 114 specimens of the short-spine taxa from the Upper Guinean Forests. Holotype of Chiloglanis fortuitus denoted by star.
The morphological comparison of C. frodobagginsi, new species, and C. micropogon included 35 measurements and eight meristics from 50 specimens. Measurements shown to be sexually dimorphic (e.g., fin lengths and length of postcleithral process) were not included in the analysis (Supplemental Table A; see Data Accessibility). Plots of principal components 1 and 2 clearly separate C. frodobagginsi, new species, from C. micropogon in the Lualaba River (Fig. 3A). Populations of Chiloglanis cf. micropogon from the Benue, Ndian, and Cross River drainages are also distinct from topotypic C. micropogon and C. frodobagginsi, new species. Occipital shield width, mandibular tooth row width, maxillary barbel length, and distance between dorsal and adipose fins contribute to variation observed in PC2 (Supplemental Table B; see Data Accessibility). In plots of PC2 to PC3, populations of C. micropogon from the Lualaba River and C. frodobagginsi, new species, are still distinct (Fig. 3B). The populations in the Moa River are also largely distinct from Niger River C. frodobagginsi, new species (Fig. 3A, B). These two specimens are only 19.4 and 20.1 mm SL so additional specimens from this population are needed to better understand the variation observed.
Fig. 3Plots of PC1 to PC2 from principal component analysis of 35 log-transformed measurements from 47 specimens (A) and PC2 to PC3 (B). The holotype of Chiloglanis frodobagginsi is noted by the black star. Refer to Supplemental Table B (see Data Accessibility) for component loading values.
The first principal component was positively correlated with standard length (Pearson's correlation = 0.99). The RMA regression of PC1 to the log-transformed standard length (not shown) shows that the slopes of populations of Chiloglanis cf. micropogon, C. micropogon, and C. frodobagginsi, new species, are equal (P = 0.14) and that there is no difference in the elevation (i.e., the y-intercept) for each group (P = 0.39). When examining just the population of C. micropogon and C. frodobagginsi, new species, there is a difference in the elevation between the two (P = 0.04). Examining individual measurements and counts does give a sense of how the allometric trajectory of some of these traits differ in C. frodobagginsi, new species, and C. micropogon (Supplemental Fig. A; see Data Accessibility). The distance between the dorsal fin and adipose fin as a percentage of standard length has equal slopes (P = 0.164), but they have significantly different elevations (P = 0.0036; Fig. 4A). The number of premaxillary teeth plotted against log-transformed standard length for each species also clearly shows that these two species are distinct (Fig. 4B).
Fig. 4Reduced-major axis regression of distance from dorsal fin to adipose fin (as a percentage of standard length) on log-transformed standard length (A). Reduced-major axis regression of log-transformed total number of premaxillary teeth on log-transformed standard length (B). Chiloglanis frodobagginsi (open circle), Chiloglanis frodobagginsi from the Moa River (filled circle), Chiloglanis micropogon (open square), and holotype of C. frodobagginsi (black star).
Chiloglanis fortuitus, Schmidt, Bragança, and Tweddle, new species
urn:lsid:zoobank.org:act:5DAB9826-ADEE-42B5-84A8-934D5CCF4511
Figure 5, Table 1
- Holotype.--SAIAB 202292, 35.0 mm SL, Liberia, St. John River drainage, Nimba County, Dayea River, above Yekepa, 7.579333°N, 8.516889°W, D. Tweddle, 30 March 2012. Diagnosis.--Chiloglanis fortuitus is distinguished from all known species of Chiloglanis, including all species in the Upper Guinean Forest, except C. disneyi, C. microps, C. niger, and C. orthodontus, in having 18 mandibular teeth in the functional row (vs. 6–15 teeth; Table 1). Chiloglanis fortuitus is easily distinguished from C. disneyi, C. microps, and C. niger in having longer mandibular barbels whereas these are absent or reduced in the latter species. Chiloglanis fortuitus is distinguished from C. orthodontus in having a more robust oral disc and its length equal to its width versus length much shorter than width (Friel and Vigliotta, 2011). Chiloglanis fortuitus is further distinguished from C. orthodontus in having a longer dorsal spine (12.8 versus 4.1–7.8 % SL) and shorter maxillary barbels (7.2 versus 9.4–14.8 % SL).
- Description.--Morphometric measurements and meristics for holotype summarized in Table 1. Dorsal, lateral, and ventral views (Fig. 5) illustrate body shape, fin shape and placement, oral disc size and shape, and maxillary and mandibular barbel lengths.
- Moderate-sized Chiloglanis, maximum standard length observed 35.0 mm in one male specimen. Body dorsally depressed anteriorly and laterally compressed posteriorly. Pre-dorsal convex, sloping ventrally towards posterior nares, pre-orbital convex. Post-dorsal body sloping ventrally towards caudal fin. Post-anal profile concave, pre-anal profile horizontal. Small unculiferous tubercles present on body, concentrations of tubercles higher near head. Lateral line complete, arising at level of orbit and sloping ventrally to midlateral alongside of body towards caudal peduncle. Urogenital papillae presumed sexually dimorphic; males with elongated urogenital papilla.
- Head depressed. Gill membranes broadly united. Gill openings restricted, opening near pectoral-fin origin to horizontal level of orbit. Occipital-nuchal shield covered and visible through skin. Eye moderate in size, located post mid-head length, horizontal axis longest, without free margins. Anterior and posterior nares equidistant, positioned mid-snout. Naris with raised rims, posterior naris with elongated anterior flap.
- Mouth inferior, upper and lower lips united to form oral disc. Oral disc moderate in size, length equaling width and covered in papillae. Barbels in three pairs; maxillary barbel originating from posterolateral region of disc, unbranched, moderate in length, 7% of SL. Lateral and medial mandibular barbels moderate, incorporated into lower lip and positioned on both sides of midline cleft on posterior margin of oral disc. Lateral barbel 5% of SL, less than twice length of medial barbel. Primary maxillary teeth “S” shaped with exposed brown tips. 72 teeth in four scattered rows on ovoid tooth pads. Secondary premaxillary teeth scattered on posterior surface of premaxillae. Tertiary teeth small and needle-like, near midline of dorsal edge of tooth plate. Mandibular teeth in one to two rows, “S” shaped and grouped near midline. Functional (anterior) row with 18 brown-tipped teeth.
- Dorsal-fin origin just posterior to anterior third of body. Dorsal fin with small spinelet, spine, and four rays. Dorsal spine moderate to short in length, reaching 13% of SL. Adipose fin medium length, reaching 17% of SL; margin convex with small notch posteriorly. Caudal fin forked with rounded lobes, lower lobe longer than upper lobe, count i, 7, 8, i. Anal-fin origin posterior to origin of adipose fin, margin convex, count iii, 6. Pelvic-fin origin at vertical between dorsal and adipose fins, margin convex, reaching beyond anal-fin origin, count i, 6. Pectoral fin with smooth spine, reaching 16% of SL, count I, 7. Postcleithral process in holotype short and pointed.
- Coloration.--Coloration of preserved specimen in Figure 5. In dorsal view, dark brown with mottled areas of medium brown. Lighter areas between nares and orbits, at origin of dorsal fin, at origin and terminus of adipose fin, and at caudal peduncle. In lateral view, specimen with yellow-buff color with overlying medium and dark brown blotches. Dark area more prevalent dorsal to midline, extending ventrally at origins of pelvic and anal fins. Dark brown melanophores scattered across body, more readily visible ventral to midline, prominent on sides of belly. Ventral surface yellow-buff colored with few melanophores scattered near pelvic and anal fins. Oral disc and barbels cream colored.
- Pectoral and dorsal spines pigmented distally, rays cream to translucent. Dorsal base of pectoral fin lightly marked by triangular area of dark brown melanophores, band of melanophores at mid-length. Dorsal fin with area of melanophores near base and mid-length. Anal fin with melanophores at base and mid-length. Pelvic fin cream with few melanophores at base and band at mid-length. Adipose fin cream to translucent with dark brown markings from region just posterior of origin to its posterior third. Caudal fin cream to translucent with dark brown areas near base, mid-length, and distal end on upper and lower lobes; lighter areas forming circular marking on upper and lower lobes.
- Etymology.--The specific epithet is “fortuitus,” referring to the fortuitous aspect of collecting this one specimen at the type locality. The collector, D. Tweddle, sampled fishes at 36 localities in the upper St. John River drainage in Liberia and collected 69 specimens of Chiloglanis at ten of these localities. Additionally, the lot that contained C. fortuitus was one of the three lots borrowed by the lead author to aid with the description of C. tweddlei (Schmidt et al., 2017). The discovery and formal description of C. fortuitus is fortuitous in several aspects.
- Distribution.--Chiloglanis fortuitus is only known from the type locality in the Dayea River above Yekepa in Nimba County, Liberia (Supplemental Fig. B; see Data Accessibility). The site looked natural, yet it had been severely impacted many years earlier by the iron ore mine upstream. It was fast flowing, of uniform depth with a bottom of gravel with small rocks, with very little natural structure (e.g., woody debris and large boulders) likely due to previous mining activities. It is interesting that this species was not collected at the other ten localities in the region that contained C. tweddlei. As with other members of Chiloglanis that are found in streams in the Upper Guinea Forests, when two species co-occur within a drainage, they usually utilize different microhabitats (Schmidt et al., 2017). Additional collection efforts in the upper St. John River drainage in Guinea and Liberia may yield additional specimens and populations of C. fortuitus.
- Remarks.--Species descriptions based on a single specimen are not ideal though in this case it is warranted. This species is morphologically distinct from congeners in the region (Fig. 2), and the number of mandibular teeth and morphology of the oral disc and barbels, characters used in the taxonomy of species of Chiloglanis, clearly separate it from all other known species of Chiloglanis. In sampling fishes at 36 localities, the collector was only able to get one specimen of C. fortuitus. Another lot from the St. John River drainage, USNM 193949, collected in the 1950s, contained 17 specimens all of which were determined to be C. tweddlei. This species is seemingly rare within the drainage and we don't know when, or even if, additional specimens of C. fortuitus will be collected. Additionally, this area is under intense pressures from the mining industry and all species present face an uncertain future. Indeed, the type specimen was collected in a stream that had previously been disturbed by iron ore mining. Formally describing this species is an important step in recognizing and conserving the freshwater biodiversity in the Upper Guinean Forests.
- Chiloglanis fortuitus resembles species of Chiloglanis that are in the short-spine group referenced in Schmidt et al. (2016, 2017). The discovery of this new species within the St. John River suggests that additional species of Chiloglanis, and other taxa, remain to be discovered and described from the region. This is especially likely for rivers in the region (e.g., Rokel, Jong, Sewa, and Mano) where collections of freshwater taxa are still lacking. While collecting this specimen was fortuitous, depositing the specimen and the others collected during an environmental impact assessment into natural history collections is what allowed this species to be discovered and described. Other new species have been collected and formerly described from similar surveys in the region (Pezold et al., 2016, 2020). We encourage practitioners in this field to continue the practice of depositing specimens collected during assessments in natural history collections so that the specimens will be available to researchers.
Table 1Morphometric measurements and meristics for holotype of Chiloglanis fortuitus. Standard length expressed in mm. All other measurements expressed in percent SL.
Chiloglanis frodobagginsi, Schmidt, Friel, Bart, and Pezold, new species
urn:lsid:zoobank.org:act:02157426-E35A-4ABB-BEF4-85047A68B5C8
Figure 6, Table 2
- Chiloglanis batesii.--Paugy and Roberts, 1992 (in part): 502–511; Paugy and Roberts, 2003 (in part): 197–207.
- Chiloglanis micropogon.--Daget, 1954 (in part): 307–308; Daget, 1959 (in part): 682–683; Daget, 1962 (in part): 115.
- Chiloglanis cf. micropogon.--Schmidt et al., 2016: 201–204.
- Chiloglanis sp. aff. micropogon.--Schmidt et al., 2017: 301–336.
- Holotype.--TU 203552, 24.1 mm SL, Guinea, Niger River, North of Faranah, on road N29, 10.28382°N, 10.76925°W, 2013 Guinea expedition team, 29 January 2013.
- Paratypes.--AMNH 263794, 4, 23.1–25.7 mm SL, AUM 59751, 8, CUMV 97679, 8, TU 203527, 4, 24.8–25.3 mm SL, Guinea, Niger River drainage, Mafou River, on road N2 ∼80 km South of Faranah, 9.53072°N, 10.40199°W, 2013 Guinea expedition team, 28 January 2013; AUM 59554, 19, CUMV 97678, 18, TU 203348, 19, 20.6–24.1 mm SL, FLMNH 249106, 5, 20.0–24.6 mm SL, Guinea, Niger River drainage, Tinkisso River, below Tinkisso Dam, 10.72793°N, 11.16855°W, 2013 Guinea expedition team, 12 January 2013; CUMV 97680, 6, TU 204171, 4, 19.2–24.3 mm SL, collected with holotype; SAIAB 203746, 9, 19.9–23.3 mm SL, USNM 437542, 9, 22.1–38.1 mm SL, Niger River drainage, Tinkisso River, at dam, 10.72°N 11.17°W, B. Samoura and others, 7 April 2003; TU 204157, 1, 20.4 mm SL, Guinea, Niger River drainage, Tinkisso River, at dam, 10.72793°N 11.16855°W, F. Pezold and others, 18 January 2003.
- Non-type material examined.--AMNH 264623, 1, 26.3 mm SL, Guinea, Niger River drainage, Tinkisso River, at Toumania, 10.57902°N, 10.47273°W, F. Pezold and others, 16 May 2003; CUMV 98653, 1, 19.4 mm SL, TU 204170, 1, 20.1 mm SL, Guinea, Moa River drainage, Masseni River, about 3 miles north of Konesseridou, 8.7204°N, 9.52436°W, 2013 Guinea expedition team, 26 January 2013; MRAC 2016.029.P.52-63, 12, 20.0–27.0 mm SL, Guinea, Niger River drainage, Tinkisso River, at Bissikrima, 10.83°N, 10.92°W, B. Samoura and others, 8 April 2003; USNM 437545, 5, 22.2–23.5 mm SL, Guinea, Niger River drainage, Niger River, north of Faranah, F. Pezold and others, 26 May 2003.
- Diagnosis.--Chiloglanis frodobagginsi is distinguished from all known species of Chiloglanis in the Upper Guinean Forests, and most of the other described species (except C. disneyi, C. harbinger, C. marlieri, C. micropogon, C. microps, C. mongoensis, and C. niger) by the very reduced, or absent, mandibular barbels on the oral disc. Chiloglanis frodobagginsi can be distinguished from C. disneyi, C. harbinger, C. marlieri, C. microps, C. mongoensis, and C. niger in having fewer mandibular teeth in one row (10–12 versus 16–20, 26–30, 26–28, 16–18, 28, and 16–20 respectively). Chiloglanis frodobagginsi is distinguished from C. batesii in having two prominent papillae on the roof of the oral cavity; versus the absence of papillae in C. batesii. This species is further distinguished from C. batesii in having shorter and more blunt mandibular teeth arranged in bunched rows; versus sharper, more elongate, and disordered mandibular teeth. Chiloglanis frodobagginsi also has a fleshy unpapillated ridge posterior to the mandibular teeth versus several large papillae in C. batesii (Friel and Vigliotta, 2011).
- A unique combination of characters distinguishes C. frodobagginsi from the closely related C. micropogon and C. cf. micropogon from Central Africa. As compared to C. micropogon from the Lualaba River, C. frodobagginsi has a larger eye diameter (4.2–6.5 versus 4.7–5.5 % SL; Supplemental Fig. A; see Data Accessibility), longer maxillary barbels (3.8–7.2 versus 3.4–6.5 % SL; Supplemental Fig. A; see Data Accessibility), a narrower mandibular tooth row (1.6–2.8 versus 2.4–3.1 % SL; Supplemental Fig. A; see Data Accessibility), a longer distance between dorsal fin and adipose fin (14.4–21.5 versus 14.9–18.8 % SL; Fig. 4A), and a shorter anal-fin base length (8.0–10.8 versus 9.7–12.7 % SL; Supplemental Fig. A; see Data Accessibility). Chiloglanis frodobagginsi is further distinguished from C. micropogon in having fewer premaxillary teeth (36–70 versus 62–103) scattered in three rows versus four (Fig. 4B; Table 2). While the ranges of these measurements and counts overlap, these distinctions hold true when comparing similar sized species (Fig. 4; Supplemental Fig. A; see Data Accessibility). Compared to Chiloglanis cf. micropogon from the Benue, Ndian, and Cross River basins Chiloglanis frodobagginsi has a narrower occipital shield (3.0–4.0 versus 4.0–5.4 % SL), a shorter dorsal fin to adipose fin distance (14.5–21.5 versus 19.3–24.2), and a narrower mandibular tooth row (1.6–2.8 versus 1.8–3.2 % SL).
- Description.--Morphometric measurements and meristics for holotype and 21 paratypes summarized in Table 2. Dorsal, lateral, and ventral views (Fig. 6) illustrate body shape, fin shape and placement, oral disc size and shape, and maxillary and mandibular barbel lengths.
- Small to moderate-sized Chiloglanis, maximum standard length 38.1 mm. Body dorsally depressed anteriorly and laterally compressed posteriorly. Pre-dorsal convex, sloping ventrally towards posterior nares, pre-orbital convex, sharply angling towards tip of snout pre-nares. Post-dorsal body sloping ventrally towards caudal fin. Post-anal profile shallowly concave, pre-anal profile horizontal to slightly convex. Small unculiferous tubercles present on body, concentrations of tubercles higher near head. Lateral line complete, arising at dorsal level of orbit and sloping ventrally to midlateral alongside of body towards caudal peduncle. Urogenital papillae sexually dimorphic; males with elongated urogenital papillae, females with reduced papillae, separated from anus by shallow invagination.
- Head depressed. Gill membranes broadly united. Gill openings restricted, opening near pectoral-fin origin to horizontal level of mid-orbit. Occipital-nuchal shield covered and visible through skin. Eye moderate in size, located post mid-head length, horizontal axis longest, without free margins. Anterior naris set farther apart than posterior naris, positioned mid-snout. Nares with raised rims, posterior naris with elongated anterior flap.
- Mouth inferior, upper and lower lips united to form oral disc. Oral disc moderate in size, slightly wider than long and covered in papillae. Maxillary barbel originating from posterolateral region of disc, unbranched, moderate in length, reaching 7% of SL. Lateral and medial mandibular barbels absent or very reduced. Two prominent papillae on roof of oral cavity. Primary maxillary teeth “S” shaped with exposed brown tips. 36–70 teeth in three scattered rows on ovoid tooth pads. Secondary premaxillary teeth scattered on posterior surface of premaxillae. Tertiary teeth small and needle-like, near midline of dorsal edge of toothplate. Mandibular teeth in one to two rows, curved and bunched near midline. Functional (anterior) row with 12 brown-tipped teeth. Distinct, slightly concave rectangular fleshy ridge posterior to mandibular teeth.
- Dorsal-fin origin just posterior to anterior third of body. Dorsal fin with small spinelet, spine, and five to six rays. Dorsal spine medium to short in length, reaching 13% of SL. Adipose fin medium length, reaching 19.6% of SL; margin convex. Caudal fin forked with rounded lobes, lower lobe longer than upper lobe, count i, 7, 8, i, no sexual dimorphism observed in examined specimens. Anal-fin origin posterior to origin of adipose fin, margin convex, count iii, 5–7. Pelvic-fin origin at vertical between dorsal and adipose fin, margins convex, reaching beyond anal-fin origin, count i, 6. Pectoral fin with smooth spine, reaching 15.6% of SL, count I, 8–9. Postcleithral process shorter and bluntly pointed, no sexual dimorphism noted in specimens examined.
- Coloration.--Typical coloration of preserved specimens in Figure 6. In dorsal view, specimens medium brown with mottled areas of light brown. Lighter areas on tip of snout anterior to nares, at origin of dorsal fin, at origin and terminus of adipose fin, and on caudal peduncle. White or cream unculiferous tubercles scattered across body, more concentrated near head. In lateral view, specimens with yellow-buff color with overlying medium brown blotches. Dark area more prevalent dorsal to midline, but extending ventrally at origin of pelvic and anal fins. Dark brown melanophores scattered across body, more readily visible ventral to midline, absent on belly. Ventral surface yellow-buff colored with few melanophores scattered near anus and origin of anal fin. Oral disc and barbels cream colored.
- Pectoral and dorsal spines pigmented distally and rays cream to translucent. Dorsal base of pectoral fin lightly marked by triangular area of dark brown melanophores, band of melanophores at mid-length. Dorsal fin with area of melanophores near base and mid-length. Anal fin with melanophores at mid-length. Pelvic fin cream with few melanophores at base and band at mid-length. Adipose fin cream to translucent with dark brown markings at origin. Caudal fin cream to translucent with dark brown areas near base and at mid-length.
- Etymology.--Chiloglanis frodobagginsi is named after another diminutive traveler, Frodo Baggins, a fictional character well known from J. R. R. Tolkien's The Lord of the Rings series. Roughly 3,000 miles (4,800 km) separate C. frodobagginsi in the upper Niger River drainage and C. micropogon, the sister species, found in the Congo River basin. Another seemingly closely related species, Chiloglanis cf. micropogon, is found in the southern Benue drainage and in several small coastal rivers about 3,000 km from the upper Niger River drainage (e.g., Cross and Ndian Rivers). It is unclear whether these species are descended from a more widespread species, or the result of dispersal from the Congo River basin into the Niger River drainage, via the Benue River, and then up to the headwaters of the Niger River. This was an incredible journey for such a small and seemingly non-vagile fish.
- Distribution.--Chiloglanis frodobagginsi occurs in the upper Niger River drainage in Guinea and further downstream in the Niger River near Bamako (Fig. 1; Daget, 1959). This species was collected in several tributaries to the Niger River in Guinea and also collected in the upper reaches of the Moa River drainage (Masseni River), a coastal river drainage. Only two specimens were collected in the Moa River drainage and no tissues were retained. Given that most species of Chiloglanis in the region are restricted to individual river drainages and since the Moa River drainage is on the other (i.e., west) side of the Guinean Range from the Niger River drainage, this population may be a distinct species. For this reason, these specimens were not included in the type material for C. frodobagginsi. In the Tinkisso River, C. frodobagginsi was collected below the waterfall over small gravel in the middle of the channel. Chiloglanis waterloti is also found in the Tinkisso River, but this species is usually associated with woody debris or large rocks.
- Remarks.--The affinity between Chiloglanis frodobagginsi and C. micropogon was first reported in research on fishes in the upper Niger River drainage (Daget, 1954, 1959). The large distance between the populations in the upper Niger River and the Lualaba River (Congo River drainage) warranted further examinations of these specimens (Daget, 1959). Daget sent specimens from the upper Niger River to Max Poll for comparison to those that Poll described as C. micropogon from the Congo River drainage (Poll, 1952; Daget, 1959). Poll noted some variation between the different populations, but it wasn't enough to readily distinguish one from the other (Daget, 1959). Daget also noted their diminutive size and rarity relative to the co-occurring specimens of C. waterloti (Daget, 1954). Herein we noted another aspect of these specimens that wasn't directly noted: the apparent lack of an elongated upper caudal-fin lobe and an elongate and spatulate postcleithral process in males. An examination of the type specimen of C. micropogon and the sketch of the holotype clearly shows an elongated upper caudal-fin lobe (Poll, 1952, fig. 3, page 228). The larger specimens collected in recent expeditions were mostly females, and none of the males collected showed an elongated upper caudal-fin lobe. More specimens of C. frodobagginsi are needed to better understand if this species also displays those sexually dimorphic characteristics, or if the lack of sexual differentiation can be a useful trait in distinguishing both species. Chiloglanis frodobagginsi is also genetically distinct from C. micropogon with a divergence observed of 3.6% in cytochrome b and 6.2% in Growth Hormone intron 2 (Schmidt et al., 2016).
- Populations of Chiloglanis cf. micropogon in the Benue, Cross, and Ndian Rivers have only been relatively recently collected (e.g., in the 1970s and 1980s) and were unknown to Daget and Poll at the time of their comparisons of upper Niger and Lualaba River specimens. In examining these specimens, they clearly concur with C. micropogon, but also differ in some respects (Fig. 3). Some specimens showed the sexual dimorphism attributed to C. micropogon (e.g., an elongated upper caudal-fin lobe and an elongated and spatulate postcleithral process), but most of the specimens examined did not have these traits. Many of these collections and subsequent identifications took place before many of the species in the region were described (Roberts, 1989) and cataloged under superficially similar species names C. niger and C. disneyi. Additional populations from the Benue and the smaller coastal drainages in Central Africa are needed to fully resolve the relationships within the C. micropogon complex.
Table 2Morphometric measurements and meristics for Chiloglanis frodobagginsi (n = 22; holotype and 21 paratypes) and topotypic Chiloglanis micropogon (n = 10). Standard length expressed in mm. All other measurements expressed in percent SL. Meristic data for holotype are identified by an asterisk (*).
DISCUSSIONThe two new species of Chiloglanis described herein provide further evidence that the Upper Guinean Forests support a wealth of biodiversity. Chiloglanis fortuitus was collected during an environmental assessment in the upper St. John River drainage in Liberia. This one specimen was serendipitously borrowed when examining type material for the description of the co-occurring C. tweddlei. The presence of multiple species within these forested streams suggests many more species remain to be discovered and formally described. Many of the streams that originate on the western slope of the Guinean Range remain relatively unexplored. As anthropogenic pressures increase in the region, it is critical that these rivers are surveyed so that this biodiversity can be documented before it is lost (Lalèyè et al., 2021).
Chiloglanis micropogon was, until recently, considered a synonym of Chiloglanis batesii (Roberts, 1989; Friel and Vigliotta, 2011). Roberts considered C. batesii to be one of the most widespread species of Chiloglanis occurring from the upper Niger River drainage to the Congo River basin, and throughout Central Africa (Roberts, 1989). Friel and Vigliotta (2011) recognized C. micropogon as a distinct taxon based on several different characters. Papillae on the roof of the oral cavity are present in C. micropogon but absent in C. batesii. These papillae are also present in the holotype of C. frodobagginsi (Fig. 6). There were also several oral disc characters mentioned (e.g., fleshy ridge posterior to mandibular teeth) that distinguished C. micropogon and C. batesii (Friel and Vigliotta, 2011). Chiloglanis batesii was likely described from Nyong River drainage in southern Cameroon (Boulenger, 1904). Populations of Chiloglanis, reported as C. batesii or C. micropogon, from the Nyong River to the Niger River need to be examined in more detail to determine the distributions of these species. Populations of Chiloglanis cf. micropogon from the Benue, Ndian, and Cross River basins appear to be distinct from topotypic C. micropogon, but additional specimens are needed from the region for confirmation (Fig. 3; Supplemental Table C; see Data Accessibility).
Understanding the diversity of Chiloglanis in the region is complicated by the presence of several species that are superficially similar to C. micropogon and C. batesii, especially smaller individuals. Chiloglanis niger also has reduced/absent mandibular barbels and around 12 mandibular teeth. The smaller individuals examined are very similar to C. micropogon, but are readily distinguished by the straight, robust mandibular teeth and smaller eye, relative to similar-sized C. micropogon. Small specimens of C. disneyi can also superficially resemble C. micropogon, but this species usually has many more mandibular teeth (16–20 versus 12) and has small mandibular barbels. Most of these species were described around the same time as several major collecting expeditions in the region (Teugels et al., 1992), and many of the specimens were deposited as Chiloglanis sp. or incorrectly placed into one of the newly described species. Sexual dimorphism in these species is also seemingly variable. One smaller male specimen of C. cf. micropogon from the Benue River clearly has an elongate and spatulate postcleithral process and elongated upper caudal-fin lobe. Another specimen, determined to be C. niger, has an elongated upper caudal-fin lobe but not an elongate postcleithral process. Another issue is the relative lack of material from the region. Many lots only contain one or a few specimens and some of those are damaged. It seems that many of these fishes are relatively rare (but may be locally abundant) and are often not sampled if electrofishers are not utilized. Examining the remaining cataloged material from this region should clarify some of these issues, but additional collecting in Cameroon and surrounding areas is also needed.
The biogeographical implications of the close relationship between the Upper Guinean Forest C. frodobagginsi and the Congolese C. micropogon are also quite interesting. A previous study (Schmidt et al., 2016) appears to offer the first molecular evidence of a recent connection between the fish fauna in the Congo River basin and the Niger River drainage. This past connection was hypothesized based on several presumptive shared taxa that occur within the Congo, Chad, and Niger River drainages (e.g., Campylomormyrus tamandua; Lévêque, 1997). Lévêque (1997) hypothesized that fishes from the Congo River first entered the Chad basin and then gained access to the Niger River drainage through the Gauthiot Falls in the upper Benue River. The presence of Chiloglanis cf. micropogon in the Benue River drainage also supports the hypothesis that this river served as a dispersal corridor for fishes in the region. These fishes could have then spread throughout the Niger River drainage, and subsequent climatic changes may have restricted them to well-watered regions within the watershed. The headwater streams of the Niger River drainage in Guinea have likely served as refugia where forests, and more importantly water, have persisted during climatic fluctuations (Mayr and O'Hara, 1986). Other fishes that are thought to occur within the Congo and Niger drainages should be investigated to see if similar patterns exist.
The presence of C. frodobagginsi in the upper Moa River also provides further evidence for headwater capture in the region. The diversity within these forested streams that arise along the Guinean Range has likely been fueled by recurring headwater capture events in the region. This would allow for species to geodisperse (vicariance) into neighboring drainages and diversify. If enough time passes before another headwater capture event, or the headwater capture event is across the Guinean Range versus alongside of it, a second or third species can become established in the system. In the Moa River system, there are three species of Chiloglanis, and within the Loffa and St. John River drainages there are two species present (Schmidt et al., 2017). These mechanisms that have probably promoted diversification within Chiloglanis have likely also promoted diversification within the mountain catfishes (Amphilius) and African small barbs (Enteromius; Schmidt and Pezold, 2011; Schmidt, 2014; Schmidt et al., 2019). Similarly, it seems that the diversity in other co-occurring groups of fishes is also vastly underestimated and needs to be investigated further.
MATERIAL EXAMINEDChiloglanis micropogon: Democratic Republic of the Congo: Congo River drainage: CUMV 97580, 10 of 101, 18.6–22.0 mm SL, Lualaba River, at main portion of Wagenia Falls, 0.49413°N, 25.20701°E; MRAC 91479, holotype, 49 mm SL, Nzokwe River, affluent of Ulindi River, Territory Kabare, 2.92°S, 28.53°E, G. Marlier, 20 May 1949.
Chiloglanis cf. micropogon: Nigeria: Benue River drainage: USNM 338276, 2, 21.3–28.0 mm SL, Mayo Santo (Fulani) or River Shuntan, small stream inflow to main river near Gashaka Camp. This eventually drains to the River Taraba which joins the River Benue, 7.3806°N, 11.4736°E. Cameroon: Cross River drainage: USNM 304265, 3, 22.4–26.3 mm SL, collecting points upper tributaries of Munaya, near Baro Village, northern Korup, Bake River below Nere Bifa Falls, 5.833°N, 9.1722°E; USNM 304331, 5, 22.3–36.3 mm SL, Akpa-Yafe System, streams and rivers of southwest Korup, Akpasang River at crossing point nearest end of ‘P’ (transect), 5.01°N, 8.75°E; Ndian River drainage: USNM 303409, 44, 25.7–27.4 mm SL, streams and rivers of southeast boundary of Korup, main Ndian River at bridge crossing into Korup, 4.9833°N, 8.85°E; USNM 303624, 1, 39.7 mm SL, streams and rivers of southeast boundary of Korup, Owaye River just north of Mana River, Korup ‘buffer zone A,’ 5.1°N, 8.9833°E.
Chiloglanis niger: Cameroon: Benue River drainage: USNM 280387, 1, 54.7 mm SL, Northwest Province, Fujua, fast flowing stream with rocky bottom, 6.28333°N, 10.28333°E (georeferenced); USNM 338335, 1, 38.9 mm SL, Mayo Dundere, the upper reaches of the Mayo Gashaka/Mayo Korngal. This eventually drains to the River Taraba which joins the River Benue, 7.0306°N, 11.5667°E; USNM 338717, 1, 41.7 mm SL, Mayo Katan, at the crossing point with a dirt road. This stream eventually drains to the River Taraba which joins the River Benue, 7.1639°N, 11.3917°E.
Chiloglanis tweddlei: Liberia: St. John River drainage: SAIAB 188313, 3, Nimba County, Kahn River upstream, 7.589167°N, 8.568611°W; SAIAB 188352, 1, Nimba County, Bold River, 7.50444°N, 8.58944°W; SAIAB 188448, 1, Nimba County, Yiti River, main road, 7.4875°N, 8.615278°W; SAIAB 188466, 3, Nimba County, Dehn River, at Lugbei, 7.608611°N, 8.622778°W; SAIAB 188551, 8, Nimba County, Yiti River, 7.516111°N, 8.704167°W; SAIAB 188582, 10, Nimba County, Yiti River upstream, 7.510278°N, 8.749167°W; SAIAB 188608, 1, Nimba County, Bee River, at Saniquellie, 7.369556°N, 8.697278°W; SAIAB 188639, 3, Nimba County, Tributary of Vellie River, 7.5755°N, 8.657722°W; USNM 193949, 17, Bong County, Gbarngy District, streams and tributary to St. John River.
DATA ACCESSIBILITYSupplemental material is available at https://www.ichthyologyandherpetology.org/i2022067. Unless an alternative copyright or statement noting that a figure is reprinted from a previous source is noted in a figure caption, the published images and illustrations in this article are licensed by the American Society of Ichthyologists and Herpetologists for use if the use includes a citation to the original source (American Society of Ichthyologists and Herpetologists, the DOI of the Ichthyology & Herpetology article, and any individual image credits listed in the figure caption) in accordance with the Creative Commons Attribution CC BY License. ZooBank publication urn:lsid:zoobank.org:pub: AA5998FE-9F91-46B2-AB49-B8EDE9B6E4DA.
ACKNOWLEDGMENTSFunding for the 2003 expeditions was provided from the Critical Ecosystem Partnership Fund administered by Conservation International, the HHMI/ULM Undergraduate Science Education Program, and by OISE 0080699 to FP. Funding for the 2013 expedition provided from the All Cypriniformes Species Inventory (ACSII, NSF DEB #1023403). We thank S. Diallo, B. Coulibaly (deceased), M. Diop, B. Samoura, B. Kaba, M. Camara, and members of the 2002–2003 ULM Guinea expeditions for assistance in the field. The 2013 expedition included J. W. Armbruster, H. L. Bart, S. Diallo, T. Diallo, J. P. Friel, M. M. Hayes, M. Magase, and M. Sou. Comparative material was generously provided by C. Dillman (CUMV) and D. Pitassy (USNM). J. Mann (TU) loaned and shipped the specimens of C. frodobagginsi to RCS so that this description could be completed, T. Vigliotta (AMNH) shared the images of the holotype of C. micropogon, and R. Robins (FLMNH) assisted in cataloging type material. Many thanks to the collections staff at SAIAB and USNM who provided PHNB and RCS with material while institutions had restricted access during the COVID-19 pandemic. Sandra Raredon (USNM) photographed the type material of C. frodobagginsi and generously worked during restricted conditions due to the pandemic.
© 2023 by the American Society of Ichthyologists and Herpetologists
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Citation Download Citation
Ray C. Schmidt, Pedro H. N. Bragança, John P. Friel, Frank Pezold, Denis Tweddle, and Henry L. Bart Jr. "Two New Species of Suckermouth Catfishes (Mochokidae: Chiloglanis) from Upper Guinean Forest Streams in West Africa," Ichthyology & Herpetology 111(3), 376-389, (31 July 2023). https://doi.org/10.1643/i2022067
Received: 18 August 2022; Accepted: 1 May 2023; Published: 31 July 2023
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DOI: 10.11646/ZOOTAXA.5318.4.5
PAGE RANGE: 515-530
ABSTRACT VIEWS: 72
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A new species Lethrinops chilingali (Cichliformes: Cichlidae) from a Lake Malawi satellite lake, believed to be extinct in the wild. ACARIAFRICAN CICHLIDHAPLOCHROMINELAKE CHILINGALIMORPHOLOGY AbstractA new species of cichlid fish, Lethrinops chilingali is described from specimens collected from Lake Chilingali, near Nkhotakota, Malawi. It is assigned to the genus Lethrinops based on the form of the lower jaw dental arcade and by the absence of traits diagnostic of the phenotypically similar Ctenopharynx, Taeniolethrinops and Tramitichromis. It also lacks the enlarged cephalic lateral line canal pores found in species of Alticorpus and Aulonocara. The presence of a broken horizontal stripe on the flanks of females and immature/non-territorial males of Lethrinops chilingali distinguishes them from all congeners, including Lethrinops lethrinus, in which the stripe is typically continuous. Lethrinops chilingali also has a relatively shorter snout, shorter lachrymal bone and less ventrally positioned mouth than Lethrinops lethrinus. It appears likely that Lethrinops chilingali is now extinct in the wild, as this narrow endemic species has not been positively recorded in the natural environment since 2009. Breeding populations remain in captivity.
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PAGE RANGE: 515-530
ABSTRACT VIEWS: 72
PDF DOWNLOADED: 0
A new species Lethrinops chilingali (Cichliformes: Cichlidae) from a Lake Malawi satellite lake, believed to be extinct in the wild. ACARIAFRICAN CICHLIDHAPLOCHROMINELAKE CHILINGALIMORPHOLOGY AbstractA new species of cichlid fish, Lethrinops chilingali is described from specimens collected from Lake Chilingali, near Nkhotakota, Malawi. It is assigned to the genus Lethrinops based on the form of the lower jaw dental arcade and by the absence of traits diagnostic of the phenotypically similar Ctenopharynx, Taeniolethrinops and Tramitichromis. It also lacks the enlarged cephalic lateral line canal pores found in species of Alticorpus and Aulonocara. The presence of a broken horizontal stripe on the flanks of females and immature/non-territorial males of Lethrinops chilingali distinguishes them from all congeners, including Lethrinops lethrinus, in which the stripe is typically continuous. Lethrinops chilingali also has a relatively shorter snout, shorter lachrymal bone and less ventrally positioned mouth than Lethrinops lethrinus. It appears likely that Lethrinops chilingali is now extinct in the wild, as this narrow endemic species has not been positively recorded in the natural environment since 2009. Breeding populations remain in captivity.
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DOI: 10.11646/ZOOTAXA.5315.6.5
A new species of cirri-bearing eel of the genus Cirrhimuraena (Anguilliformes: Ophichthidae) from the coastal Bay of Bengal, IndiaPISCESFISHNEW SPECIESODISHA FRINGED-LIP EELPALUR CANALAbstractA new species of cirri-bearing ophichthidae eel Cirrhimuraena odishaensis sp. nov. is described here, on the basis of two specimens collected from the Palur canal and Talasari fish landing centre in Odisha, India. The distinguishing characters of Cirrhimuraena odishaensis sp. nov. that separate it from its congeners include the presence of a single row of mandibular teeth, origin of the dorsal fin directly above the midpoint of pectoral fin, vertebral counts (pre-dorsal 10, pre-anal 46–47, and total 160–162), and number of cirri (13) on the upper jaw. Morphologically Cirrhimuraena odishaensis shows close affinity with Cirrhimuraena yuanding and Cirrhimuraena orientalis. The new species differs from C. yuanding by origin of dorsal fin, number of intermaxillary and maxillary teeth, and length of head. The new species differs from C. orientalis with relatively higher vertebrae.
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A new species of cirri-bearing eel of the genus Cirrhimuraena (Anguilliformes: Ophichthidae) from the coastal Bay of Bengal, IndiaPISCESFISHNEW SPECIESODISHA FRINGED-LIP EELPALUR CANALAbstractA new species of cirri-bearing ophichthidae eel Cirrhimuraena odishaensis sp. nov. is described here, on the basis of two specimens collected from the Palur canal and Talasari fish landing centre in Odisha, India. The distinguishing characters of Cirrhimuraena odishaensis sp. nov. that separate it from its congeners include the presence of a single row of mandibular teeth, origin of the dorsal fin directly above the midpoint of pectoral fin, vertebral counts (pre-dorsal 10, pre-anal 46–47, and total 160–162), and number of cirri (13) on the upper jaw. Morphologically Cirrhimuraena odishaensis shows close affinity with Cirrhimuraena yuanding and Cirrhimuraena orientalis. The new species differs from C. yuanding by origin of dorsal fin, number of intermaxillary and maxillary teeth, and length of head. The new species differs from C. orientalis with relatively higher vertebrae.
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Squatina leae • Revision of the Western Indian Ocean Angel Sharks, Genus Squatina (Squatiniformes: Squatinidae), with Description of A New Species and Redescription of the African Angel Shark Squatina africana Regan, 1908
Squatina leae
Weigmann, Vaz, Akhilesh, Leeney & Naylor, 2023
DOI: 10.3390/biology12070975
Abstract
Sampling efforts on the Saya de Malha Bank (part of the Mascarene Plateau, western Indian Ocean) unveiled three unusual small juvenile angel shark specimens, that were a much paler color than the only known western Indian Ocean species, Squatina africana Regan, 1908. However, it took many years before further specimens, including adults of both sexes, and tissue samples were collected. The present manuscript contains a redescription of S. africana based on the holotype and additional material, as well as the formal description of the new species of Squatina. All specimens of the new species, hereafter referred to as Squatina leae sp. nov., were collected in the western Indian Ocean off southwestern India and on the Mascarene Plateau at depths of 100–500 m. The new species differs from S. africana in a number of characteristics including its coloration when fresh, smaller size at birth, size at maturity, and adult size, genetic composition, and distribution. Taxonomic characteristics include differences in the morphology of the pectoral skeleton and posterior nasal flap, denticle arrangement and morphology, vertebral counts, trunk width, pectoral–pelvic space, and clasper size. A key to the species of Squatina in the Indian Ocean is provided.
Keywords: Chondrichthyes; Elasmobranchii; angel sharks; systematics; taxonomy; diversity; morphology; PCA; mCT scans; genetics; NADH2; CO1
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, in (a) dorsolateral, (b) dorsal, and (c) ventral views in fresh condition.
Photographs kindly provided by P. U. Zacharia (ICAR-CMFRI).
Scale bar: 5 cm.
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, head in (a) dorsal and (b) ventral views, (c) clasper region in dorsal view, (d) anterior pectoral-fin margin in dorsofrontal view, (e) dorsal fins in dorsal view, and (f) caudal fin in dorsolateral view.
Photographs (a–d,f) kindly provided by P. U. Zacharia (ICAR-CMFRI) show the holotype in fresh condition, photograph (e) shows the holotype in preserved condition.
Family Squatinidae Bonaparte, 1838
Genus Squatina Duméril, 1806
Squatina leae sp. nov.
English name: Lea’s angel shark
Spanish name: Angelote de Lea
German name: Leas Engelhai
Diagnosis. A small angel shark species (maximum size 870 mm TL) with the following characteristics: dorsal coloration conspicuously bright, beige to light grayish-brown, with many light yellowish flecks on trunk, and pectoral and pelvic fins, as well as countless densely set, minute dark spots, partially forming pseudocelli, all over the dorsal surface; no median row of scute-like denticles on trunk; anterior nasal flap with two lateral, elongate barbels and a medial rectangular barbel, all with ventral margins slightly fringed to almost smooth; concave between eyes; posterior nasal flap with an additional barblet; pectoral-pelvic space 10.0–14.9% TL; pectoral-fin apex angular; pelvic-fin free rear tips not reaching level of first dorsal-fin origin; tail moderately long, its length from cloaca 50.2–58.5% TL; pectoral fins moderately long, length 31.1–35.2% TL; dorsal fins not lobe-like; first dorsal-fin base somewhat longer than second dorsal-fin base; caudal fin of adults with angular apices; monospondylous centra 43–46; diplospondylous precaudal centra 55–58; total precaudal centra 100–104; total vertebral centra 130–136; and pectoral-fin skeleton with propterygium articulating with four radials.
Geographic distribution—The new species is currently known from the western Indian Ocean on the Mascarene Plateau and off southwestern India in 100–500 m depths (Figure 10).
Etymology--The name is dedicated to the memory of Lea-Marie Cordt, the late sister of the first author’s fiancée.
Squatina leae sp. nov., paratypes ZMH 26097, juvenile male, 298 mm TL fresh (in dorsal view) and ZMH 26098, juvenile male, 259 mm TL fresh (in ventral view) taken directly after catching.
The photograph was taken and kindly provided by Matthias F. W. Stehmann.
Scale bar: 5 cm.
Conclusions:
The recognition of a new species, Squatina leae sp. nov., with the redescription of S. africana, clarifies the taxonomic status and distribution of these two western Indian Ocean angel shark species. This is essential for improved data collection and research and for more effective conservation and management policy decisions. Accordingly, this information must be incorporated into future conservation and management plans of sharks in the western Indian Ocean. The current lack of conservation plans at all scales in this ocean area, as well as the need for more research, will likely jeopardize the populations of western Indian Ocean angel sharks in the future.
Simon Weigmann, Diego F. B. Vaz, K. V. Akhilesh, Ruth H. Leeney and Gavin J. P. Naylor. 2023. Revision of the Western Indian Ocean Angel Sharks, Genus Squatina (Squatiniformes, Squatinidae), with Description of a New Species and Redescription of the African Angel Shark Squatina africana Regan, 1908. Biology. 12(7), 975. DOI: 10.3390/biology12070975
Simple Summary: Angel sharks (genus Squatina) are small- to medium-sized sharks with flattened bodies, that live on the seafloor. Until now, 23 valid species of angel sharks have been identified around the world, of which over half are thought to be facing a moderate to severe risk of extinction. Several juvenile angel sharks were collected by researchers working on the Mascarene Plateau, an elevated area of seabed in the Indian Ocean, in 1988 and 1989. They appeared different in coloration and in body shape and structure to a species known from East Africa and Madagascar, the African angel shark. Additional angel sharks were caught off the western coast of India in 2016 and in the central western Indian Ocean in 2017, including adult individuals. Information on body measurements and skeleton structure were collected, and genetic analyses were also conducted on these sharks and on museum specimens previously identified as African angel sharks. The results indicated that the specimens collected from the Mascarene Plateau and off southwestern India were a species that is new to science. It is genetically and morphologically distinct from the African angel shark; is smaller when born and when fully grown; and lives in a distinctly different area. The newly described species has been named Lea’s angel shark.
Squatina leae
Weigmann, Vaz, Akhilesh, Leeney & Naylor, 2023
DOI: 10.3390/biology12070975
Abstract
Sampling efforts on the Saya de Malha Bank (part of the Mascarene Plateau, western Indian Ocean) unveiled three unusual small juvenile angel shark specimens, that were a much paler color than the only known western Indian Ocean species, Squatina africana Regan, 1908. However, it took many years before further specimens, including adults of both sexes, and tissue samples were collected. The present manuscript contains a redescription of S. africana based on the holotype and additional material, as well as the formal description of the new species of Squatina. All specimens of the new species, hereafter referred to as Squatina leae sp. nov., were collected in the western Indian Ocean off southwestern India and on the Mascarene Plateau at depths of 100–500 m. The new species differs from S. africana in a number of characteristics including its coloration when fresh, smaller size at birth, size at maturity, and adult size, genetic composition, and distribution. Taxonomic characteristics include differences in the morphology of the pectoral skeleton and posterior nasal flap, denticle arrangement and morphology, vertebral counts, trunk width, pectoral–pelvic space, and clasper size. A key to the species of Squatina in the Indian Ocean is provided.
Keywords: Chondrichthyes; Elasmobranchii; angel sharks; systematics; taxonomy; diversity; morphology; PCA; mCT scans; genetics; NADH2; CO1
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, in (a) dorsolateral, (b) dorsal, and (c) ventral views in fresh condition.
Photographs kindly provided by P. U. Zacharia (ICAR-CMFRI).
Scale bar: 5 cm.
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, head in (a) dorsal and (b) ventral views, (c) clasper region in dorsal view, (d) anterior pectoral-fin margin in dorsofrontal view, (e) dorsal fins in dorsal view, and (f) caudal fin in dorsolateral view.
Photographs (a–d,f) kindly provided by P. U. Zacharia (ICAR-CMFRI) show the holotype in fresh condition, photograph (e) shows the holotype in preserved condition.
Family Squatinidae Bonaparte, 1838
Genus Squatina Duméril, 1806
Squatina leae sp. nov.
English name: Lea’s angel shark
Spanish name: Angelote de Lea
German name: Leas Engelhai
Diagnosis. A small angel shark species (maximum size 870 mm TL) with the following characteristics: dorsal coloration conspicuously bright, beige to light grayish-brown, with many light yellowish flecks on trunk, and pectoral and pelvic fins, as well as countless densely set, minute dark spots, partially forming pseudocelli, all over the dorsal surface; no median row of scute-like denticles on trunk; anterior nasal flap with two lateral, elongate barbels and a medial rectangular barbel, all with ventral margins slightly fringed to almost smooth; concave between eyes; posterior nasal flap with an additional barblet; pectoral-pelvic space 10.0–14.9% TL; pectoral-fin apex angular; pelvic-fin free rear tips not reaching level of first dorsal-fin origin; tail moderately long, its length from cloaca 50.2–58.5% TL; pectoral fins moderately long, length 31.1–35.2% TL; dorsal fins not lobe-like; first dorsal-fin base somewhat longer than second dorsal-fin base; caudal fin of adults with angular apices; monospondylous centra 43–46; diplospondylous precaudal centra 55–58; total precaudal centra 100–104; total vertebral centra 130–136; and pectoral-fin skeleton with propterygium articulating with four radials.
Geographic distribution—The new species is currently known from the western Indian Ocean on the Mascarene Plateau and off southwestern India in 100–500 m depths (Figure 10).
Etymology--The name is dedicated to the memory of Lea-Marie Cordt, the late sister of the first author’s fiancée.
Squatina leae sp. nov., paratypes ZMH 26097, juvenile male, 298 mm TL fresh (in dorsal view) and ZMH 26098, juvenile male, 259 mm TL fresh (in ventral view) taken directly after catching.
The photograph was taken and kindly provided by Matthias F. W. Stehmann.
Scale bar: 5 cm.
Conclusions:
The recognition of a new species, Squatina leae sp. nov., with the redescription of S. africana, clarifies the taxonomic status and distribution of these two western Indian Ocean angel shark species. This is essential for improved data collection and research and for more effective conservation and management policy decisions. Accordingly, this information must be incorporated into future conservation and management plans of sharks in the western Indian Ocean. The current lack of conservation plans at all scales in this ocean area, as well as the need for more research, will likely jeopardize the populations of western Indian Ocean angel sharks in the future.
Simon Weigmann, Diego F. B. Vaz, K. V. Akhilesh, Ruth H. Leeney and Gavin J. P. Naylor. 2023. Revision of the Western Indian Ocean Angel Sharks, Genus Squatina (Squatiniformes, Squatinidae), with Description of a New Species and Redescription of the African Angel Shark Squatina africana Regan, 1908. Biology. 12(7), 975. DOI: 10.3390/biology12070975
Simple Summary: Angel sharks (genus Squatina) are small- to medium-sized sharks with flattened bodies, that live on the seafloor. Until now, 23 valid species of angel sharks have been identified around the world, of which over half are thought to be facing a moderate to severe risk of extinction. Several juvenile angel sharks were collected by researchers working on the Mascarene Plateau, an elevated area of seabed in the Indian Ocean, in 1988 and 1989. They appeared different in coloration and in body shape and structure to a species known from East Africa and Madagascar, the African angel shark. Additional angel sharks were caught off the western coast of India in 2016 and in the central western Indian Ocean in 2017, including adult individuals. Information on body measurements and skeleton structure were collected, and genetic analyses were also conducted on these sharks and on museum specimens previously identified as African angel sharks. The results indicated that the specimens collected from the Mascarene Plateau and off southwestern India were a species that is new to science. It is genetically and morphologically distinct from the African angel shark; is smaller when born and when fully grown; and lives in a distinctly different area. The newly described species has been named Lea’s angel shark.
==========================
Squatina leae
Weigmann, Vaz, Akhilesh, Leeney & Naylor, 2023
DOI: 10.3390/biology12070975
Abstract
Sampling efforts on the Saya de Malha Bank (part of the Mascarene Plateau, western Indian Ocean) unveiled three unusual small juvenile angel shark specimens, that were a much paler color than the only known western Indian Ocean species, Squatina africana Regan, 1908. However, it took many years before further specimens, including adults of both sexes, and tissue samples were collected. The present manuscript contains a redescription of S. africana based on the holotype and additional material, as well as the formal description of the new species of Squatina. All specimens of the new species, hereafter referred to as Squatina leae sp. nov., were collected in the western Indian Ocean off southwestern India and on the Mascarene Plateau at depths of 100–500 m. The new species differs from S. africana in a number of characteristics including its coloration when fresh, smaller size at birth, size at maturity, and adult size, genetic composition, and distribution. Taxonomic characteristics include differences in the morphology of the pectoral skeleton and posterior nasal flap, denticle arrangement and morphology, vertebral counts, trunk width, pectoral–pelvic space, and clasper size. A key to the species of Squatina in the Indian Ocean is provided.
Keywords: Chondrichthyes; Elasmobranchii; angel sharks; systematics; taxonomy; diversity; morphology; PCA; mCT scans; genetics; NADH2; CO1
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, in (a) dorsolateral, (b) dorsal, and (c) ventral views in fresh condition.
Photographs kindly provided by P. U. Zacharia (ICAR-CMFRI).
Scale bar: 5 cm.
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, head in (a) dorsal and (b) ventral views, (c) clasper region in dorsal view, (d) anterior pectoral-fin margin in dorsofrontal view, (e) dorsal fins in dorsal view, and (f) caudal fin in dorsolateral view.
Photographs (a–d,f) kindly provided by P. U. Zacharia (ICAR-CMFRI) show the holotype in fresh condition, photograph (e) shows the holotype in preserved condition.
Family Squatinidae Bonaparte, 1838
Genus Squatina Duméril, 1806
Squatina leae sp. nov.
English name: Lea’s angel shark
Spanish name: Angelote de Lea
German name: Leas Engelhai
Diagnosis. A small angel shark species (maximum size 870 mm TL) with the following characteristics: dorsal coloration conspicuously bright, beige to light grayish-brown, with many light yellowish flecks on trunk, and pectoral and pelvic fins, as well as countless densely set, minute dark spots, partially forming pseudocelli, all over the dorsal surface; no median row of scute-like denticles on trunk; anterior nasal flap with two lateral, elongate barbels and a medial rectangular barbel, all with ventral margins slightly fringed to almost smooth; concave between eyes; posterior nasal flap with an additional barblet; pectoral-pelvic space 10.0–14.9% TL; pectoral-fin apex angular; pelvic-fin free rear tips not reaching level of first dorsal-fin origin; tail moderately long, its length from cloaca 50.2–58.5% TL; pectoral fins moderately long, length 31.1–35.2% TL; dorsal fins not lobe-like; first dorsal-fin base somewhat longer than second dorsal-fin base; caudal fin of adults with angular apices; monospondylous centra 43–46; diplospondylous precaudal centra 55–58; total precaudal centra 100–104; total vertebral centra 130–136; and pectoral-fin skeleton with propterygium articulating with four radials.
Geographic distribution—The new species is currently known from the western Indian Ocean on the Mascarene Plateau and off southwestern India in 100–500 m depths (Figure 10).
Etymology--The name is dedicated to the memory of Lea-Marie Cordt, the late sister of the first author’s fiancée.
Squatina leae sp. nov., paratypes ZMH 26097, juvenile male, 298 mm TL fresh (in dorsal view) and ZMH 26098, juvenile male, 259 mm TL fresh (in ventral view) taken directly after catching.
The photograph was taken and kindly provided by Matthias F. W. Stehmann.
Scale bar: 5 cm.
Conclusions:
The recognition of a new species, Squatina leae sp. nov., with the redescription of S. africana, clarifies the taxonomic status and distribution of these two western Indian Ocean angel shark species. This is essential for improved data collection and research and for more effective conservation and management policy decisions. Accordingly, this information must be incorporated into future conservation and management plans of sharks in the western Indian Ocean. The current lack of conservation plans at all scales in this ocean area, as well as the need for more research, will likely jeopardize the populations of western Indian Ocean angel sharks in the future.
Simon Weigmann, Diego F. B. Vaz, K. V. Akhilesh, Ruth H. Leeney and Gavin J. P. Naylor. 2023. Revision of the Western Indian Ocean Angel Sharks, Genus Squatina (Squatiniformes, Squatinidae), with Description of a New Species and Redescription of the African Angel Shark Squatina africana Regan, 1908. Biology. 12(7), 975. DOI: 10.3390/biology12070975
Simple Summary: Angel sharks (genus Squatina) are small- to medium-sized sharks with flattened bodies, that live on the seafloor. Until now, 23 valid species of angel sharks have been identified around the world, of which over half are thought to be facing a moderate to severe risk of extinction. Several juvenile angel sharks were collected by researchers working on the Mascarene Plateau, an elevated area of seabed in the Indian Ocean, in 1988 and 1989. They appeared different in coloration and in body shape and structure to a species known from East Africa and Madagascar, the African angel shark. Additional angel sharks were caught off the western coast of India in 2016 and in the central western Indian Ocean in 2017, including adult individuals. Information on body measurements and skeleton structure were collected, and genetic analyses were also conducted on these sharks and on museum specimens previously identified as African angel sharks. The results indicated that the specimens collected from the Mascarene Plateau and off southwestern India were a species that is new to science. It is genetically and morphologically distinct from the African angel shark; is smaller when born and when fully grown; and lives in a distinctly different area. The newly described species has been named Lea’s angel shark.
Squatina leae
Weigmann, Vaz, Akhilesh, Leeney & Naylor, 2023
DOI: 10.3390/biology12070975
Abstract
Sampling efforts on the Saya de Malha Bank (part of the Mascarene Plateau, western Indian Ocean) unveiled three unusual small juvenile angel shark specimens, that were a much paler color than the only known western Indian Ocean species, Squatina africana Regan, 1908. However, it took many years before further specimens, including adults of both sexes, and tissue samples were collected. The present manuscript contains a redescription of S. africana based on the holotype and additional material, as well as the formal description of the new species of Squatina. All specimens of the new species, hereafter referred to as Squatina leae sp. nov., were collected in the western Indian Ocean off southwestern India and on the Mascarene Plateau at depths of 100–500 m. The new species differs from S. africana in a number of characteristics including its coloration when fresh, smaller size at birth, size at maturity, and adult size, genetic composition, and distribution. Taxonomic characteristics include differences in the morphology of the pectoral skeleton and posterior nasal flap, denticle arrangement and morphology, vertebral counts, trunk width, pectoral–pelvic space, and clasper size. A key to the species of Squatina in the Indian Ocean is provided.
Keywords: Chondrichthyes; Elasmobranchii; angel sharks; systematics; taxonomy; diversity; morphology; PCA; mCT scans; genetics; NADH2; CO1
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, in (a) dorsolateral, (b) dorsal, and (c) ventral views in fresh condition.
Photographs kindly provided by P. U. Zacharia (ICAR-CMFRI).
Scale bar: 5 cm.
Squatina leae sp. nov., holotype, CMFRI GA. 15.2.5.4, adult male, 671 mm TL, head in (a) dorsal and (b) ventral views, (c) clasper region in dorsal view, (d) anterior pectoral-fin margin in dorsofrontal view, (e) dorsal fins in dorsal view, and (f) caudal fin in dorsolateral view.
Photographs (a–d,f) kindly provided by P. U. Zacharia (ICAR-CMFRI) show the holotype in fresh condition, photograph (e) shows the holotype in preserved condition.
Family Squatinidae Bonaparte, 1838
Genus Squatina Duméril, 1806
Squatina leae sp. nov.
English name: Lea’s angel shark
Spanish name: Angelote de Lea
German name: Leas Engelhai
Diagnosis. A small angel shark species (maximum size 870 mm TL) with the following characteristics: dorsal coloration conspicuously bright, beige to light grayish-brown, with many light yellowish flecks on trunk, and pectoral and pelvic fins, as well as countless densely set, minute dark spots, partially forming pseudocelli, all over the dorsal surface; no median row of scute-like denticles on trunk; anterior nasal flap with two lateral, elongate barbels and a medial rectangular barbel, all with ventral margins slightly fringed to almost smooth; concave between eyes; posterior nasal flap with an additional barblet; pectoral-pelvic space 10.0–14.9% TL; pectoral-fin apex angular; pelvic-fin free rear tips not reaching level of first dorsal-fin origin; tail moderately long, its length from cloaca 50.2–58.5% TL; pectoral fins moderately long, length 31.1–35.2% TL; dorsal fins not lobe-like; first dorsal-fin base somewhat longer than second dorsal-fin base; caudal fin of adults with angular apices; monospondylous centra 43–46; diplospondylous precaudal centra 55–58; total precaudal centra 100–104; total vertebral centra 130–136; and pectoral-fin skeleton with propterygium articulating with four radials.
Geographic distribution—The new species is currently known from the western Indian Ocean on the Mascarene Plateau and off southwestern India in 100–500 m depths (Figure 10).
Etymology--The name is dedicated to the memory of Lea-Marie Cordt, the late sister of the first author’s fiancée.
Squatina leae sp. nov., paratypes ZMH 26097, juvenile male, 298 mm TL fresh (in dorsal view) and ZMH 26098, juvenile male, 259 mm TL fresh (in ventral view) taken directly after catching.
The photograph was taken and kindly provided by Matthias F. W. Stehmann.
Scale bar: 5 cm.
Conclusions:
The recognition of a new species, Squatina leae sp. nov., with the redescription of S. africana, clarifies the taxonomic status and distribution of these two western Indian Ocean angel shark species. This is essential for improved data collection and research and for more effective conservation and management policy decisions. Accordingly, this information must be incorporated into future conservation and management plans of sharks in the western Indian Ocean. The current lack of conservation plans at all scales in this ocean area, as well as the need for more research, will likely jeopardize the populations of western Indian Ocean angel sharks in the future.
Simon Weigmann, Diego F. B. Vaz, K. V. Akhilesh, Ruth H. Leeney and Gavin J. P. Naylor. 2023. Revision of the Western Indian Ocean Angel Sharks, Genus Squatina (Squatiniformes, Squatinidae), with Description of a New Species and Redescription of the African Angel Shark Squatina africana Regan, 1908. Biology. 12(7), 975. DOI: 10.3390/biology12070975
Simple Summary: Angel sharks (genus Squatina) are small- to medium-sized sharks with flattened bodies, that live on the seafloor. Until now, 23 valid species of angel sharks have been identified around the world, of which over half are thought to be facing a moderate to severe risk of extinction. Several juvenile angel sharks were collected by researchers working on the Mascarene Plateau, an elevated area of seabed in the Indian Ocean, in 1988 and 1989. They appeared different in coloration and in body shape and structure to a species known from East Africa and Madagascar, the African angel shark. Additional angel sharks were caught off the western coast of India in 2016 and in the central western Indian Ocean in 2017, including adult individuals. Information on body measurements and skeleton structure were collected, and genetic analyses were also conducted on these sharks and on museum specimens previously identified as African angel sharks. The results indicated that the specimens collected from the Mascarene Plateau and off southwestern India were a species that is new to science. It is genetically and morphologically distinct from the African angel shark; is smaller when born and when fully grown; and lives in a distinctly different area. The newly described species has been named Lea’s angel shark.
==========================
Heterodontus marshallae • Species in Disguise: A New Species of Hornshark (Heterodontiformes: Heterodontidae) from Northern Australia
Heterodontus marshallae
White, Mollen, O’Neill, Yang & Naylor, 2023
Painted Hornshark || DOI: 10.3390/d15070849
twitter.com/WillWhiteSharks
Abstract
A new species of hornshark is described from northwestern Australia based on six whole specimens and a single egg case. Heterodontus marshallae n. sp. was previously considered to be conspecific with H. zebra from the Western Pacific. The new species differs from H. zebra in the sequence of its NADH2 gene, several morphological characters, egg case morphology and key coloration features. Despite the coloration being similar between H. marshallae n. sp. and H. zebra, i.e., pale background with 22 dark brown bands and saddles, they differ consistently in two key aspects. Firstly, the snout of H. marshallae n. sp. has a dark semicircular bar, usually bifurcated for most of its length vs. a pointed, triangular shaped dark marking in H. zebra. Secondly, H. zebra has a dark bar originating below the posterior gill slits and extending onto anterior pectoral fin, which is absent in H. marshallae n. sp. The Heterodontus marshallae n. sp. is endemic to northwestern Australia and occurs in deeper waters (125–229 m) than H. zebra (0–143 m).
Keywords: Heterodontus; taxonomy; species complex; egg case; morphology; genetics
Holotype of Heterodontus marshallae n. sp. (WAM P.35408-007, adolescent male, 541 mm TL), fresh: (a) dorsal view; (b) lateral view.
Lateral view of female paratypes of Heterodontus marshallae n. sp., fresh:
(a) WAM P.26193-010, juvenile, 355 mm TL;
(b) CSIRO H 6581-01, 580 mm TL (image flipped, right side of specimen shown).
Heterodontus marshallae n. sp.
Diagnosis: A small species of hornshark with the following combination of characters: colour pattern consisting of 22 dark bands and saddles; snout with a semicircular dark bar, usually bifurcated for most of its length; no dark bar below posterior gill slits extending onto anterior pectoral fin; anal fin well separated from caudal fin (anal-caudal space 11.0–13.5% TL); ventral lobe of caudal fin prominent (lower postventral margin 4.7–6.1% TL); dorsal spines long (exposed first dorsal spine length 3.9–4.5% TL); dorsal fins taller in juveniles than adults; symphyseal and anterior teeth pointed, lateral teeth molariform with a longitudinal keel; 20–22 tooth files in upper jaw, 17–19 in lower jaw; total vertebral centra 106–112, precaudal centra 70–76, monospondylous centra 33–37; egg case with narrow, curved, screw-like keels with 1.5 rotations from anterior to posterior margins.
Etymology:
The specific name is in honour of Dr. Lindsay Marshall (www.stickfigurefish.com.au (accessed 10 May 2023)), a scientific illustrator and elasmobranch scientist who expertly painted all the sharks and rays of the world for the Chondrichthyan Tree of Life Project.
The vernacular name proposed is painted hornshark, in allusion to not only the beautiful coloration of the species but also to its namesake, who has painted all the hornsharks in amazing detail.
Egg case of: (a) Heterodontus marshallae n. sp., preserved (paratype, NTM S.18275-001); (b) H. zebra, preserved (KAUM-I. 69456); (c) H. portusjacksoni, preserved (CSIRO H 8732-02).
William T. White, Frederik H. Mollen, Helen L. O’Neill, Lei Yang and Gavin J. P. Naylor. 2023. Species in Disguise: A New Species of Hornshark from Northern Australia (Heterodontiformes: Heterodontidae). Diversity. 15(7), 849. DOI: 10.3390/d15070849
(This article belongs to the Special Issue Genetic Connectivity, Species Diversity and Conservation Biology of Chondrichthyes)
twitter.com/WillWhiteSharks/status/1679337718546075650
==========================
Heterodontus marshallae
White, Mollen, O’Neill, Yang & Naylor, 2023
Painted Hornshark || DOI: 10.3390/d15070849
twitter.com/WillWhiteSharks
Abstract
A new species of hornshark is described from northwestern Australia based on six whole specimens and a single egg case. Heterodontus marshallae n. sp. was previously considered to be conspecific with H. zebra from the Western Pacific. The new species differs from H. zebra in the sequence of its NADH2 gene, several morphological characters, egg case morphology and key coloration features. Despite the coloration being similar between H. marshallae n. sp. and H. zebra, i.e., pale background with 22 dark brown bands and saddles, they differ consistently in two key aspects. Firstly, the snout of H. marshallae n. sp. has a dark semicircular bar, usually bifurcated for most of its length vs. a pointed, triangular shaped dark marking in H. zebra. Secondly, H. zebra has a dark bar originating below the posterior gill slits and extending onto anterior pectoral fin, which is absent in H. marshallae n. sp. The Heterodontus marshallae n. sp. is endemic to northwestern Australia and occurs in deeper waters (125–229 m) than H. zebra (0–143 m).
Keywords: Heterodontus; taxonomy; species complex; egg case; morphology; genetics
Holotype of Heterodontus marshallae n. sp. (WAM P.35408-007, adolescent male, 541 mm TL), fresh: (a) dorsal view; (b) lateral view.
Lateral view of female paratypes of Heterodontus marshallae n. sp., fresh:
(a) WAM P.26193-010, juvenile, 355 mm TL;
(b) CSIRO H 6581-01, 580 mm TL (image flipped, right side of specimen shown).
Heterodontus marshallae n. sp.
Diagnosis: A small species of hornshark with the following combination of characters: colour pattern consisting of 22 dark bands and saddles; snout with a semicircular dark bar, usually bifurcated for most of its length; no dark bar below posterior gill slits extending onto anterior pectoral fin; anal fin well separated from caudal fin (anal-caudal space 11.0–13.5% TL); ventral lobe of caudal fin prominent (lower postventral margin 4.7–6.1% TL); dorsal spines long (exposed first dorsal spine length 3.9–4.5% TL); dorsal fins taller in juveniles than adults; symphyseal and anterior teeth pointed, lateral teeth molariform with a longitudinal keel; 20–22 tooth files in upper jaw, 17–19 in lower jaw; total vertebral centra 106–112, precaudal centra 70–76, monospondylous centra 33–37; egg case with narrow, curved, screw-like keels with 1.5 rotations from anterior to posterior margins.
Etymology:
The specific name is in honour of Dr. Lindsay Marshall (www.stickfigurefish.com.au (accessed 10 May 2023)), a scientific illustrator and elasmobranch scientist who expertly painted all the sharks and rays of the world for the Chondrichthyan Tree of Life Project.
The vernacular name proposed is painted hornshark, in allusion to not only the beautiful coloration of the species but also to its namesake, who has painted all the hornsharks in amazing detail.
Egg case of: (a) Heterodontus marshallae n. sp., preserved (paratype, NTM S.18275-001); (b) H. zebra, preserved (KAUM-I. 69456); (c) H. portusjacksoni, preserved (CSIRO H 8732-02).
William T. White, Frederik H. Mollen, Helen L. O’Neill, Lei Yang and Gavin J. P. Naylor. 2023. Species in Disguise: A New Species of Hornshark from Northern Australia (Heterodontiformes: Heterodontidae). Diversity. 15(7), 849. DOI: 10.3390/d15070849
(This article belongs to the Special Issue Genetic Connectivity, Species Diversity and Conservation Biology of Chondrichthyes)
twitter.com/WillWhiteSharks/status/1679337718546075650
==========================
Cryptocoryne vinzelii (Araceae) • A New Species of Water Trumpet from Basilan Island, Philippines [Discovery through Citizen Science II]
Cryptocoryne vinzelii Naive,
in Naive, Duhaylungsod et Jacobsen, 2023.
taiwania.NTU.edu.tw/abstract/1938
facebook.com/TaiwaniaOffice
twitter.com/orchidARCIIae
Abstract
A new Sulu Archipelago endemic species, Cryptocoryne vinzelii, is herein described and illustrated discovered by a citizen scientist in the island of Basilan. A detailed description, colour plates, phenology, distribution and a provisional conservation status are presented. With the recent discovery of a new species, the biodiversity of the Philippines has expanded, revealing a total of 10 distinct Cryptocoryne taxa, of which nine are known to be endemic. This new finding underscores the country's remarkable ecological richness and highlights the importance of citizen science in preserving and studying its unique flora.
Keyword: Aroid, critically endangered, Cryptocoryne palawanensis, Cryptocoryne pygmaea, Sulu Archipelago, BARMM
Cryptocoryne vinzelii Naive
A. Spathe B. Spadix C. Detail of limb D. Infructescence.
Photos from A.B. Duhaylungsod & MAK Naive 137 prepared by: MAK Naive.
In situ photograph of Cryptocoryne vinzelii showing its habit.
Photo by: AB Duhaylungsod.
Cryotocoryne vinzelii Naive, sp. nov.
Diagnosis: This new species resembles Cryptocoryne palawanensis Bastmeijer, N.Jacobsen & Naive (Naive et al., 2022b) but differs significantly in having these following characters: smaller, broader, robust leaves; 4– 7 mm long peduncle; erect, wide opened, upright limb; and up to 40 male flowers
Etymology: Named after the son of the citizen scientist (2nd author) who discovered the species, Vinzel D. Duhaylungsod.
Mark Arcebal K. Naive, Alvin B. Duhaylungsod and Niels Jacobsen. 2023. Discovery through Citizen Science II: Cryptocoryne vinzelii (Araceae), A New Species of Water Trumpet from Basilan Island, Philippines. Taiwania. 68(3); 294-297. DOI: 10.6165/tai.2023.68.294
taiwania.NTU.edu.tw/abstract/1938
facebook.com/TaiwaniaOffice/posts/3403827936505678
twitter.com/orchidARCIIae/status/1677959422650490881
==========================
Cryptocoryne vinzelii Naive,
in Naive, Duhaylungsod et Jacobsen, 2023.
taiwania.NTU.edu.tw/abstract/1938
facebook.com/TaiwaniaOffice
twitter.com/orchidARCIIae
Abstract
A new Sulu Archipelago endemic species, Cryptocoryne vinzelii, is herein described and illustrated discovered by a citizen scientist in the island of Basilan. A detailed description, colour plates, phenology, distribution and a provisional conservation status are presented. With the recent discovery of a new species, the biodiversity of the Philippines has expanded, revealing a total of 10 distinct Cryptocoryne taxa, of which nine are known to be endemic. This new finding underscores the country's remarkable ecological richness and highlights the importance of citizen science in preserving and studying its unique flora.
Keyword: Aroid, critically endangered, Cryptocoryne palawanensis, Cryptocoryne pygmaea, Sulu Archipelago, BARMM
Cryptocoryne vinzelii Naive
A. Spathe B. Spadix C. Detail of limb D. Infructescence.
Photos from A.B. Duhaylungsod & MAK Naive 137 prepared by: MAK Naive.
In situ photograph of Cryptocoryne vinzelii showing its habit.
Photo by: AB Duhaylungsod.
Cryotocoryne vinzelii Naive, sp. nov.
Diagnosis: This new species resembles Cryptocoryne palawanensis Bastmeijer, N.Jacobsen & Naive (Naive et al., 2022b) but differs significantly in having these following characters: smaller, broader, robust leaves; 4– 7 mm long peduncle; erect, wide opened, upright limb; and up to 40 male flowers
Etymology: Named after the son of the citizen scientist (2nd author) who discovered the species, Vinzel D. Duhaylungsod.
Mark Arcebal K. Naive, Alvin B. Duhaylungsod and Niels Jacobsen. 2023. Discovery through Citizen Science II: Cryptocoryne vinzelii (Araceae), A New Species of Water Trumpet from Basilan Island, Philippines. Taiwania. 68(3); 294-297. DOI: 10.6165/tai.2023.68.294
taiwania.NTU.edu.tw/abstract/1938
facebook.com/TaiwaniaOffice/posts/3403827936505678
twitter.com/orchidARCIIae/status/1677959422650490881
==========================
New, Huge Cavefish Species, Neolissochilus pnar, Described
www.reef2rainforest.com/2023/07/06/new-huge-cavefish-species-neolissochilus-pnar-described/
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www.reef2rainforest.com/2023/07/06/new-huge-cavefish-species-neolissochilus-pnar-described/
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DOI: 10.11646/ZOOTAXA.5315.1.6
Glyptothorax viridis, a new species of catfish (Teleostei: Siluriformes: Sisoridae) from Manipur, IndiaPISCESGLYPTOTHORAX VIRIDISNEW SPECIESCHAKPI RIVERCHINDWIN DRAINAGEINDO-BURMARHEOPHILIC SISORIDAbstractGlyptothorax viridis, new species, is described from the Dujang, a hill stream tributary of the Chakpi River, Chindwin drainage in Manipur, India. It is distinguished from its congeners by the following combination of characters: presence of plicae on paired fins; thoracic adhesive apparatus with a deep, cone-shaped median depression opening caudally; a slender pelvic fin reaching the anal fin, and tuberculated skin with three stripes on the body.
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Glyptothorax viridis, a new species of catfish (Teleostei: Siluriformes: Sisoridae) from Manipur, IndiaPISCESGLYPTOTHORAX VIRIDISNEW SPECIESCHAKPI RIVERCHINDWIN DRAINAGEINDO-BURMARHEOPHILIC SISORIDAbstractGlyptothorax viridis, new species, is described from the Dujang, a hill stream tributary of the Chakpi River, Chindwin drainage in Manipur, India. It is distinguished from its congeners by the following combination of characters: presence of plicae on paired fins; thoracic adhesive apparatus with a deep, cone-shaped median depression opening caudally; a slender pelvic fin reaching the anal fin, and tuberculated skin with three stripes on the body.
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DOI: 10.11646/ZOOTAXA.5315.1.2
Glyptothorax vatandousti, a new species of torrent catfish from the upper Karkheh drainage in Iran (Teleostei: Sisoridae)PISCESBARCODINGFRESHWATER FISHTAXONOMYWESTERN ASIAAbstractGlyptothorax vatandousti, new species, from the upper Karkheh drainage, a tributary of the Iranian Tigris, is distinguished from its congeners in the Persian Gulf basin by having the flank with a fine, pale-brown mottled pattern overlaid by small and large, blackish or dark-brown blotches, deep caudal-peduncle (its depth 1.1–1.3 times in length), and without, or with a pale-brown triangle-shaped blotch in front of dorsal-fin origin.
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Glyptothorax vatandousti, a new species of torrent catfish from the upper Karkheh drainage in Iran (Teleostei: Sisoridae)PISCESBARCODINGFRESHWATER FISHTAXONOMYWESTERN ASIAAbstractGlyptothorax vatandousti, new species, from the upper Karkheh drainage, a tributary of the Iranian Tigris, is distinguished from its congeners in the Persian Gulf basin by having the flank with a fine, pale-brown mottled pattern overlaid by small and large, blackish or dark-brown blotches, deep caudal-peduncle (its depth 1.1–1.3 times in length), and without, or with a pale-brown triangle-shaped blotch in front of dorsal-fin origin.
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A new species of Parauchenoglanis (Auchenoglanididae: Siluriformes) from the Upper Lualaba River (Upper Congo), with further evidence of hidden species diversity within the genusYonela Sithole, Tobias Musschoot, Charlotte E. T. Huyghe, Albert Chakona, Emmanuel J. W. M. N. Vreven
First published: 11 April 2023
https://doi.org/10.1111/jfb.15309urn:lsid:zoobank.org:pub:762B314B-31FF-4715-A186-86A14BAD2A4B
Albert Chakona and Emmanuel J. W. M. N. Vreven made an equal contribution to this work.
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SHAREAbstractParauchenoglanis zebratus sp. nov. is a new species endemic to the Upper Lualaba in the Upper Congo Basin. It is distinguished from all its congeners known from the Congo Basin and adjacent basins by the presence of (1) distinctive dark-brown or black vertical bars on the lateral side of the body, at least for specimens about ≥120 mm LS, (2) a broad and triangular humeral process embedded under the skin and (3) a well-serrated pectoral-fin spine. Genetic analysis based on mtDNA COI sequences confirmed the genetic distinctiveness (2.8%–13.6% K2P genetic divergence) of P. zebratus sp. nov. from congeners within the Congo and adjacent river basins. The study also revealed additional undocumented diversity within P. ngamensis, P. pantherinus, P. punctatus and P. balayi, indicating the need for further in-depth alpha-taxonomic attention to provide more accurate species delimitations for this genus. The discovery of yet another new species endemic to the Upper Lualaba, and this well outside the currently established protected areas, highlights the critical need for further assessments to accurately document the species diversity to guide freshwater conservation prioritisation and biodiversity management in this region.
==========================
First published: 11 April 2023
https://doi.org/10.1111/jfb.15309urn:lsid:zoobank.org:pub:762B314B-31FF-4715-A186-86A14BAD2A4B
Albert Chakona and Emmanuel J. W. M. N. Vreven made an equal contribution to this work.
Read the full text
TOOLS
SHAREAbstractParauchenoglanis zebratus sp. nov. is a new species endemic to the Upper Lualaba in the Upper Congo Basin. It is distinguished from all its congeners known from the Congo Basin and adjacent basins by the presence of (1) distinctive dark-brown or black vertical bars on the lateral side of the body, at least for specimens about ≥120 mm LS, (2) a broad and triangular humeral process embedded under the skin and (3) a well-serrated pectoral-fin spine. Genetic analysis based on mtDNA COI sequences confirmed the genetic distinctiveness (2.8%–13.6% K2P genetic divergence) of P. zebratus sp. nov. from congeners within the Congo and adjacent river basins. The study also revealed additional undocumented diversity within P. ngamensis, P. pantherinus, P. punctatus and P. balayi, indicating the need for further in-depth alpha-taxonomic attention to provide more accurate species delimitations for this genus. The discovery of yet another new species endemic to the Upper Lualaba, and this well outside the currently established protected areas, highlights the critical need for further assessments to accurately document the species diversity to guide freshwater conservation prioritisation and biodiversity management in this region.
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Molecular species delimitation and description of a new species of Phenacogaster (Teleostei, Characidae) from the southern Amazon basin
Camila S. Souza, George M. T. Mattox, George Vita, Luz E. Ochoa, Bruno F. Melo, Claudio OliveiraAbstractPhenacogaster is the most species-rich genus of the subfamily Characinae with 23 valid species broadly distributed in riverine systems of South America. Despite the taxonomic diversity of the genus, little has been advanced about its molecular diversity. A recent molecular phylogeny indicated the presence of undescribed species within Phenacogaster that is formally described here. We sampled 73 specimens of Phenacogaster and sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene in order to undertake species delimitation analyses and evaluate their intra- and interspecific genetic diversity. The results show the presence of 14 species, 13 of which are valid and one undescribed. The new species is known from the tributaries of the Xingu basin, the Rio das Mortes of the Araguaia basin, and the Rio Teles Pires of the Tapajós basin. It is distinguished by the incomplete lateral line, position of the humeral blotch near the pseudotympanum, and shape of the caudal-peduncle blotch. Meristic data and genetic differentiation relative to other Phenacogaster species represent strong evidence for the recognition of the new species and highlight the occurrence of an additional lineage of P. franciscoensis.
KeywordsBiodiversity, Characinae, mitochondrial DNA, Neotropical freshwater fishes, Phenacogasterini
IntroductionThe Neotropical fish subfamily Characinae encompasses small- to medium-sized tetras found across South America and in Panama and Costa Rica (Lucena and Menezes 2003; Mattox et al. 2018). Most members of this subfamily have the anterodorsal region of the body with a gibbosity (except for Acestrocephalus Eigenmann, 1910 and Phenacogaster Eigenmann, 1907) and diverse trophic strategies, including carnivory, omnivory, and lepidophagy (Géry 1977; Sazima 1984). The subfamily sensu Souza et al. (2022) currently comprises 85 valid species distributed among seven genera: Acanthocharax Eigenmann, 1912, Acestrocephalus, Charax Scopoli, 1777, Cynopotamus Valenciennes, 1850, Galeocharax Fowler, 1910, Phenacogaster, and Roeboides Günther, 1864. Phenacogaster stands out as the largest and most taxonomically complex genus within Characinae, with 23 species distributed across cis-Andean South American riverine habitats (Fricke et al. 2023). They are small fishes measuring up to 6 cm standard length (SL) and are often known as “lambaris”, “glass tetras”, “mojaritas”, and “yaya” (Lucena and Malabarba 2010).
Relative to other Characinae genera, Phenacogaster possesses two longitudinal series of elongate and imbricated scales producing a zigzag pattern in a flat preventral region, as well as the outer premaxillary tooth row divided into a medial and a lateral section separated by a diastema (Eigenmann 1917; Malabarba and Lucena 1995; Mattox and Toledo-Piza 2012). Lucena and Malabarba (2010) presented the most comprehensive taxonomic revision of the genus with descriptions of nine species of Phenacogaster, nearly doubling the species diversity, and an identification key for the species, with the exception of the so-called Phenacogaster pectinata complex with P. pectinata (Cope, 1870), P. microstictus Eigenmann, 1909, P. beni Eigenmann, 1911 and P. suborbitalis (Ahl, 1936). Recently, three more species from the Brazilian Shield have been described: P. naevata Antonetti, Lucena & Lucena, 2018; P. eurytaenia Antonetti, Lucena & Lucena, 2018 from the Tocantins basin (Antonetti et al. 2018); and P. julliae Lucena & Lucena, 2019 from the Rio São Francisco (Lucena and Lucena 2019).
No study has been conducted to assess the interspecific genetic diversity of Phenacogaster, although species delimitation methods have been used for such purposes in other Characidae (Rossini et al. 2016; García-Melo et al. 2019; Brito et al. 2021; Malabarba et al. 2021; Mattox et al. 2023). A recent molecular phylogeny of Characinae revealed the presence of the two clades in Phenacogaster, the P. pectinata clade and the P. franciscoensis clade, as well as an undescribed species of Phenacogaster from the Xingu basin (Souza et al. 2022). To further investigate this question, we used mitochondrial data and species delimitation techniques to estimate intra- and interspecific genetic diversity within the genus. The results confirmed the presence of a new species in the upper Rio Xingu of the Amazonian Brazilian Shield, which is formally described in this paper.
==========================
Camila S. Souza, George M. T. Mattox, George Vita, Luz E. Ochoa, Bruno F. Melo, Claudio OliveiraAbstractPhenacogaster is the most species-rich genus of the subfamily Characinae with 23 valid species broadly distributed in riverine systems of South America. Despite the taxonomic diversity of the genus, little has been advanced about its molecular diversity. A recent molecular phylogeny indicated the presence of undescribed species within Phenacogaster that is formally described here. We sampled 73 specimens of Phenacogaster and sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene in order to undertake species delimitation analyses and evaluate their intra- and interspecific genetic diversity. The results show the presence of 14 species, 13 of which are valid and one undescribed. The new species is known from the tributaries of the Xingu basin, the Rio das Mortes of the Araguaia basin, and the Rio Teles Pires of the Tapajós basin. It is distinguished by the incomplete lateral line, position of the humeral blotch near the pseudotympanum, and shape of the caudal-peduncle blotch. Meristic data and genetic differentiation relative to other Phenacogaster species represent strong evidence for the recognition of the new species and highlight the occurrence of an additional lineage of P. franciscoensis.
KeywordsBiodiversity, Characinae, mitochondrial DNA, Neotropical freshwater fishes, Phenacogasterini
IntroductionThe Neotropical fish subfamily Characinae encompasses small- to medium-sized tetras found across South America and in Panama and Costa Rica (Lucena and Menezes 2003; Mattox et al. 2018). Most members of this subfamily have the anterodorsal region of the body with a gibbosity (except for Acestrocephalus Eigenmann, 1910 and Phenacogaster Eigenmann, 1907) and diverse trophic strategies, including carnivory, omnivory, and lepidophagy (Géry 1977; Sazima 1984). The subfamily sensu Souza et al. (2022) currently comprises 85 valid species distributed among seven genera: Acanthocharax Eigenmann, 1912, Acestrocephalus, Charax Scopoli, 1777, Cynopotamus Valenciennes, 1850, Galeocharax Fowler, 1910, Phenacogaster, and Roeboides Günther, 1864. Phenacogaster stands out as the largest and most taxonomically complex genus within Characinae, with 23 species distributed across cis-Andean South American riverine habitats (Fricke et al. 2023). They are small fishes measuring up to 6 cm standard length (SL) and are often known as “lambaris”, “glass tetras”, “mojaritas”, and “yaya” (Lucena and Malabarba 2010).
Relative to other Characinae genera, Phenacogaster possesses two longitudinal series of elongate and imbricated scales producing a zigzag pattern in a flat preventral region, as well as the outer premaxillary tooth row divided into a medial and a lateral section separated by a diastema (Eigenmann 1917; Malabarba and Lucena 1995; Mattox and Toledo-Piza 2012). Lucena and Malabarba (2010) presented the most comprehensive taxonomic revision of the genus with descriptions of nine species of Phenacogaster, nearly doubling the species diversity, and an identification key for the species, with the exception of the so-called Phenacogaster pectinata complex with P. pectinata (Cope, 1870), P. microstictus Eigenmann, 1909, P. beni Eigenmann, 1911 and P. suborbitalis (Ahl, 1936). Recently, three more species from the Brazilian Shield have been described: P. naevata Antonetti, Lucena & Lucena, 2018; P. eurytaenia Antonetti, Lucena & Lucena, 2018 from the Tocantins basin (Antonetti et al. 2018); and P. julliae Lucena & Lucena, 2019 from the Rio São Francisco (Lucena and Lucena 2019).
No study has been conducted to assess the interspecific genetic diversity of Phenacogaster, although species delimitation methods have been used for such purposes in other Characidae (Rossini et al. 2016; García-Melo et al. 2019; Brito et al. 2021; Malabarba et al. 2021; Mattox et al. 2023). A recent molecular phylogeny of Characinae revealed the presence of the two clades in Phenacogaster, the P. pectinata clade and the P. franciscoensis clade, as well as an undescribed species of Phenacogaster from the Xingu basin (Souza et al. 2022). To further investigate this question, we used mitochondrial data and species delimitation techniques to estimate intra- and interspecific genetic diversity within the genus. The results confirmed the presence of a new species in the upper Rio Xingu of the Amazonian Brazilian Shield, which is formally described in this paper.
==========================
DOI: 10.11646/ZOOTAXA.5311.3.3
Species of Garra (Cyprinidae: Labeoninae) in the Salween River basin with description of an enigmatic new species from the Ataran River drainage of Thailand and Myanmar PISCESACTINOPTERYGIITELEOSTPHYLOGENETICSZAMI RIVER
Garra panitvongi
Tangjitjaroen, Randall, Tongnunui, Boyd & Page, 2023
ปลาเลียหินหางแดง | Redtail Garra || DOI: 10.11646/zootaxa.5311.3.3
facebook.com/ThaiFishBook
Abstract
Garra panitvongi, new species, is described from the Ataran River drainage, Salween River basin, of southeastern Myanmar and western Thailand. It is the sixth species of Garra known from the Salween River basin and is readily distinguished from all congeners by the red-orange color of the body and caudal fin, and a pointed proboscis with a blue stripe on each side from the anterior margin of the orbit to the tip of the proboscis and with the stripes forming a V-shape. Garra panitvongi is known in the aquarium trade as the Redtail Garra. Descriptive information is provided on poorly known species of Garra in the Salween River basin, and Garra nujiangensis is transferred to Ageneiogarra.
Key words: Actinopterygii, teleost, phylogenetics, Zami River
Garra panitvongi, THNHM-F021641, 67.8 mm SL, holotype;
Thailand: Zami River basin: Kanchanaburi Province: Kasat River, 5.5 km NE Ban Thi Rai Pa [village], ..., 4 February 2020.
Upper live, lower preserved.
(A) Type locality of Garra panitvongi and (B) G. panitvongi in Kasat River, Kanchanaburi Province, Thailand.
Photos in B by Nonn Panitvong.
Garra panitvongi, new species
Redtail Garra, ปลาเลียหินหางแดง
Diagnosis. Garra panitvongi is easily distinguished from all other species of Garra by the red-orange color of the caudal fin and posterior one-fourth of the body (Fig. 3), and a pointed proboscis with a blue stripe on each side from the anterior margin of the orbit to the tip of the proboscis and with the stripes forming a V-shape (Fig. 4). It further differs from G. notata and G. salweenica, the only other species of Garra in the Salween River basin with a proboscis, by lacking conspicuous black spots at the base of the dorsal fin and large black spots or bands on the caudal fin. It further differs from G. salweenica in having fewer pectoral rays (14–15 vs.17–18).
Etymology. The specific name panitvongi, a noun in genitive case, is applied in recognition of the tremendous contributions made by Dr. Nonn Panitvong to our knowledge of fishes of Thailand, in particular through his book, “A Photographic Guide to Freshwater Fishes of Thailand” (Panitvong 2020). facebook.com/ThaiFishBook
Weerapongse Tangjitjaroen, Zachary S. Randall, Sampan Tongnunui, David A. Boyd and Lawrence M. Page. 2023. Species of Garra (Cyprinidae: Labeoninae) in the Salween River Basin with Description of An Enigmatic New Species from the Ataran River Drainage of Thailand and Myanmar. Zootaxa. 5311(3); 375-392. DOI: 10.11646/zootaxa.5311.3.3
facebook.com/ThaiFishBook/posts/715195443950985
==========================
Species of Garra (Cyprinidae: Labeoninae) in the Salween River basin with description of an enigmatic new species from the Ataran River drainage of Thailand and Myanmar PISCESACTINOPTERYGIITELEOSTPHYLOGENETICSZAMI RIVER
Garra panitvongi
Tangjitjaroen, Randall, Tongnunui, Boyd & Page, 2023
ปลาเลียหินหางแดง | Redtail Garra || DOI: 10.11646/zootaxa.5311.3.3
facebook.com/ThaiFishBook
Abstract
Garra panitvongi, new species, is described from the Ataran River drainage, Salween River basin, of southeastern Myanmar and western Thailand. It is the sixth species of Garra known from the Salween River basin and is readily distinguished from all congeners by the red-orange color of the body and caudal fin, and a pointed proboscis with a blue stripe on each side from the anterior margin of the orbit to the tip of the proboscis and with the stripes forming a V-shape. Garra panitvongi is known in the aquarium trade as the Redtail Garra. Descriptive information is provided on poorly known species of Garra in the Salween River basin, and Garra nujiangensis is transferred to Ageneiogarra.
Key words: Actinopterygii, teleost, phylogenetics, Zami River
Garra panitvongi, THNHM-F021641, 67.8 mm SL, holotype;
Thailand: Zami River basin: Kanchanaburi Province: Kasat River, 5.5 km NE Ban Thi Rai Pa [village], ..., 4 February 2020.
Upper live, lower preserved.
(A) Type locality of Garra panitvongi and (B) G. panitvongi in Kasat River, Kanchanaburi Province, Thailand.
Photos in B by Nonn Panitvong.
Garra panitvongi, new species
Redtail Garra, ปลาเลียหินหางแดง
Diagnosis. Garra panitvongi is easily distinguished from all other species of Garra by the red-orange color of the caudal fin and posterior one-fourth of the body (Fig. 3), and a pointed proboscis with a blue stripe on each side from the anterior margin of the orbit to the tip of the proboscis and with the stripes forming a V-shape (Fig. 4). It further differs from G. notata and G. salweenica, the only other species of Garra in the Salween River basin with a proboscis, by lacking conspicuous black spots at the base of the dorsal fin and large black spots or bands on the caudal fin. It further differs from G. salweenica in having fewer pectoral rays (14–15 vs.17–18).
Etymology. The specific name panitvongi, a noun in genitive case, is applied in recognition of the tremendous contributions made by Dr. Nonn Panitvong to our knowledge of fishes of Thailand, in particular through his book, “A Photographic Guide to Freshwater Fishes of Thailand” (Panitvong 2020). facebook.com/ThaiFishBook
Weerapongse Tangjitjaroen, Zachary S. Randall, Sampan Tongnunui, David A. Boyd and Lawrence M. Page. 2023. Species of Garra (Cyprinidae: Labeoninae) in the Salween River Basin with Description of An Enigmatic New Species from the Ataran River Drainage of Thailand and Myanmar. Zootaxa. 5311(3); 375-392. DOI: 10.11646/zootaxa.5311.3.3
facebook.com/ThaiFishBook/posts/715195443950985
==========================
DOI: 10.11646/ZOOTAXA.5311.3.2
A revision of the gudgeon genus Hypseleotris (Gobiiformes: Gobioidei: Eleotridae) of northwest Australia, describing three new species and synonymizing the genus Kimberleyeleotris PISCESELEOTRIDAERANGE-RESTRICTEDFRESHWATERBIODIVERSITYTAXONOMYSYSTEMATICS AbstractSpecies within the northwest Australian clade of Hypseleotris (six species) and the genus Kimberleyeleotris (two species) are reviewed following the recording of new populations in the region and a molecular study of the group that identified three undescribed candidate species. Based on the analysis of extensive morphological and nuclear and mitochondrial molecular datasets, Kimberleyeleotris is here formally synonymised with Hypseleotris. Furthermore, three species from the Kimberley region, Western Australia, are described to science: Hypseleotris maranda sp. nov., Hypseleotris wunduwala sp. nov., and Hypseleotris garawudjirri sp. nov. The presence of, or number of scales across the head and body, the pattern of sensory papillae on the head, fin ray counts, dorsal and anal fin colouration (particularly in breeding males), and body depth, can be used to distinguish the members of the northwest Australia lineage. Furthermore, the newly described species were genetically separated from all northwest Australian congeners by K2P distances ranging from 7.8–11.3% based on the CO1 gene, and 7.7–16.3 % based on the entire mitochondrial genome. Two of the new species, H. maranda sp. nov. and H. wunduwala sp. nov., have extremely narrow ranges being found in single sub-catchments of the Roe and King Edward Rivers respectively. On the other hand, H. garawudjirri sp. nov. is moderately widespread, being found across the Charnley, Calder, and Sale rivers. While the conservation risk to H. maranda sp. nov. and H. wunduwala sp. nov. is inherently high due to their small range, there are currently no obvious local threatening processes to either of these species given their remote locations that are little impacted by human activities.
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A revision of the gudgeon genus Hypseleotris (Gobiiformes: Gobioidei: Eleotridae) of northwest Australia, describing three new species and synonymizing the genus Kimberleyeleotris PISCESELEOTRIDAERANGE-RESTRICTEDFRESHWATERBIODIVERSITYTAXONOMYSYSTEMATICS AbstractSpecies within the northwest Australian clade of Hypseleotris (six species) and the genus Kimberleyeleotris (two species) are reviewed following the recording of new populations in the region and a molecular study of the group that identified three undescribed candidate species. Based on the analysis of extensive morphological and nuclear and mitochondrial molecular datasets, Kimberleyeleotris is here formally synonymised with Hypseleotris. Furthermore, three species from the Kimberley region, Western Australia, are described to science: Hypseleotris maranda sp. nov., Hypseleotris wunduwala sp. nov., and Hypseleotris garawudjirri sp. nov. The presence of, or number of scales across the head and body, the pattern of sensory papillae on the head, fin ray counts, dorsal and anal fin colouration (particularly in breeding males), and body depth, can be used to distinguish the members of the northwest Australia lineage. Furthermore, the newly described species were genetically separated from all northwest Australian congeners by K2P distances ranging from 7.8–11.3% based on the CO1 gene, and 7.7–16.3 % based on the entire mitochondrial genome. Two of the new species, H. maranda sp. nov. and H. wunduwala sp. nov., have extremely narrow ranges being found in single sub-catchments of the Roe and King Edward Rivers respectively. On the other hand, H. garawudjirri sp. nov. is moderately widespread, being found across the Charnley, Calder, and Sale rivers. While the conservation risk to H. maranda sp. nov. and H. wunduwala sp. nov. is inherently high due to their small range, there are currently no obvious local threatening processes to either of these species given their remote locations that are little impacted by human activities.
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DOI: 10.11646/ZOOTAXA.5311.1.4
Two new freshwater blennies from the Eastern Mediterranean basin (Teleostei: Blenniidae)PISCESCOI BARCODE REGIONCEYHAN DRAINAGESEYHAN DRAINAGEMOLECULAR DISTANCEAbstractTwo new species of Salariopsis are described from the Eastern Mediterranean basin. Salariopsis burcuae, new species, from the Bay of Antalya east to the Jordan, is characterised by having a short cirrus, usually not overlapping the 9th circum-orbital sensory pore, and many tiny black dots on the cheek not organised in rows or bands. The new species shows a 4.1% K2P sequence divergence on the cytochrome-c-oxidase subunit 1 (COI) barcoding region from its closest relative, S. fluviatilis. Salariopsis renatorum, new species, from the upper Ceyhan drainage and a coastal stream in Arsuz, is distinguished by having an unbranched supraocular tentacle, black lateral line pores, a short snout, and no black dots on the upper part of the flank and on the cheek. It is also distinguished from its geographically closest congener, S. burcuae, by a molecular distance of 8.8% K2P in its COI barcode region.
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Two new freshwater blennies from the Eastern Mediterranean basin (Teleostei: Blenniidae)PISCESCOI BARCODE REGIONCEYHAN DRAINAGESEYHAN DRAINAGEMOLECULAR DISTANCEAbstractTwo new species of Salariopsis are described from the Eastern Mediterranean basin. Salariopsis burcuae, new species, from the Bay of Antalya east to the Jordan, is characterised by having a short cirrus, usually not overlapping the 9th circum-orbital sensory pore, and many tiny black dots on the cheek not organised in rows or bands. The new species shows a 4.1% K2P sequence divergence on the cytochrome-c-oxidase subunit 1 (COI) barcoding region from its closest relative, S. fluviatilis. Salariopsis renatorum, new species, from the upper Ceyhan drainage and a coastal stream in Arsuz, is distinguished by having an unbranched supraocular tentacle, black lateral line pores, a short snout, and no black dots on the upper part of the flank and on the cheek. It is also distinguished from its geographically closest congener, S. burcuae, by a molecular distance of 8.8% K2P in its COI barcode region.
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Pseudolaguvia permaris • A New Catfish (Siluriformes: Sisoridae) from the Eastern Ghats of India
Pseudolaguvia permaris
Vijayakrishnan, Praveenraj & Mishra, 2023
DOI: 10.11646/zootaxa.5297.2.6
twitter.com/Meenkaran1
Abstract
Pseudolaguvia permaris, a new sisorid catfish is described from the Mahanadi River basin in Odisha, India. The new species can be distinguished from congeners in having the following combination of characters: serrated anterior margin of dorsal-fin spine, thoracic adhesive apparatus not extending beyond base of last pectoral-fin ray, caudal peduncle depth 8.6–10.2% SL, body depth at anus 15.3–20.2% SL, adipose-fin base length 13.6–18.1% SL, dorsal to adipose distance 11.4–14.4% SL, length of pectoral-fin spine 19.3–28.0% SL, length of dorsal-fin spine 16.5–20.4% SL, head width 21.6–25.9% SL and indistinct, creamish bands on the body.
Keywords: Pisces, Siluriformes, Sisoroidea, Odisha, Mahanadi River, biogeography
Balaji Vijayakrishnan, Jayasimhan Praveenraj and Abhisek Mishra. 2023. Pseudolaguvia permaris, A New Catfish from the Eastern Ghats of India (Teleostei: Sisoridae). Zootaxa. 5297(2); 271-281. DOI: 10.11646/zootaxa.5297.2.6
twitter.com/Meenkaran1/status/1669724664455626753
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Pseudolaguvia permaris
Vijayakrishnan, Praveenraj & Mishra, 2023
DOI: 10.11646/zootaxa.5297.2.6
twitter.com/Meenkaran1
Abstract
Pseudolaguvia permaris, a new sisorid catfish is described from the Mahanadi River basin in Odisha, India. The new species can be distinguished from congeners in having the following combination of characters: serrated anterior margin of dorsal-fin spine, thoracic adhesive apparatus not extending beyond base of last pectoral-fin ray, caudal peduncle depth 8.6–10.2% SL, body depth at anus 15.3–20.2% SL, adipose-fin base length 13.6–18.1% SL, dorsal to adipose distance 11.4–14.4% SL, length of pectoral-fin spine 19.3–28.0% SL, length of dorsal-fin spine 16.5–20.4% SL, head width 21.6–25.9% SL and indistinct, creamish bands on the body.
Keywords: Pisces, Siluriformes, Sisoroidea, Odisha, Mahanadi River, biogeography
Balaji Vijayakrishnan, Jayasimhan Praveenraj and Abhisek Mishra. 2023. Pseudolaguvia permaris, A New Catfish from the Eastern Ghats of India (Teleostei: Sisoridae). Zootaxa. 5297(2); 271-281. DOI: 10.11646/zootaxa.5297.2.6
twitter.com/Meenkaran1/status/1669724664455626753
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Labeo mbimbii,
Description of Two New Labeo (Labeoninae; Cyprinidae) Endemic to the Lulua River in the Democratic Republic of Congo (Kasai Ecoregion); a Hotspot of Fish Diversity in the Congo Basin
Tobit L.D. Liyandja, Melanie L.J. Stiassny
Author Affiliations +
American Museum Novitates, 2023(3999):1-22 (2023). https://doi.org/10.1206/3999.1
AbstractLabeo mbimbii, n. sp., and Labeo manasseeae, n. sp., two small-bodied Labeo species, are described from the lower and middle reaches of the Lulua River (Kasai ecoregion, Congo basin) in the Democratic Republic of Congo. The two new species are members of the L. forskalii species group and are genetically distinct from all other species of that clade. Morphologically they can be distinguished from central African L. forskalii group congeners except L. dhonti, L. lukulae, L. luluae, L. parvus, L. quadribarbis, and L. simpsoni in the possession of 29 or fewer (vs. 30 or more) vertebrae and from those congeners by a wider interpectoral, among other features.
The two new species are endemic to the Lulua River and, although overlapping in geographical range and most meristic and morphometric measures, are readily differentiated by differing numbers of fully developed supraneural bones, predorsal vertebrae, snout morphology, and additional osteological features. The description of these two species brings the total of Labeo species endemic to the Lulua basin to three. The third endemic species, L. luluae, was previously known only from the juvenile holotype, but numerous additional specimens have now been identified. The cooccurrence of 14 Labeo species in the Lulua River, three of which are endemic, highlights this system as a hotspot of Labeo diversity in the Congo basin and across the continent.
Citation Download Citation
Tobit L.D. Liyandja and Melanie L.J. Stiassny "Description of Two New Labeo (Labeoninae; Cyprinidae) Endemic to the Lulua River in the Democratic Republic of Congo (Kasai Ecoregion); a Hotspot of Fish Diversity in the Congo Basin," American Museum Novitates 2023(3999), 1-22, (18 May 2023). https://doi.org/10.1206/3999.1
Published: 18 May 2023
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Tobit L.D. Liyandja, Melanie L.J. Stiassny
Author Affiliations +
American Museum Novitates, 2023(3999):1-22 (2023). https://doi.org/10.1206/3999.1
AbstractLabeo mbimbii, n. sp., and Labeo manasseeae, n. sp., two small-bodied Labeo species, are described from the lower and middle reaches of the Lulua River (Kasai ecoregion, Congo basin) in the Democratic Republic of Congo. The two new species are members of the L. forskalii species group and are genetically distinct from all other species of that clade. Morphologically they can be distinguished from central African L. forskalii group congeners except L. dhonti, L. lukulae, L. luluae, L. parvus, L. quadribarbis, and L. simpsoni in the possession of 29 or fewer (vs. 30 or more) vertebrae and from those congeners by a wider interpectoral, among other features.
The two new species are endemic to the Lulua River and, although overlapping in geographical range and most meristic and morphometric measures, are readily differentiated by differing numbers of fully developed supraneural bones, predorsal vertebrae, snout morphology, and additional osteological features. The description of these two species brings the total of Labeo species endemic to the Lulua basin to three. The third endemic species, L. luluae, was previously known only from the juvenile holotype, but numerous additional specimens have now been identified. The cooccurrence of 14 Labeo species in the Lulua River, three of which are endemic, highlights this system as a hotspot of Labeo diversity in the Congo basin and across the continent.
Citation Download Citation
Tobit L.D. Liyandja and Melanie L.J. Stiassny "Description of Two New Labeo (Labeoninae; Cyprinidae) Endemic to the Lulua River in the Democratic Republic of Congo (Kasai Ecoregion); a Hotspot of Fish Diversity in the Congo Basin," American Museum Novitates 2023(3999), 1-22, (18 May 2023). https://doi.org/10.1206/3999.1
Published: 18 May 2023
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- Original Paper
- Published: 09 June 2023
- 17 Accesses
- 3 Altmetric
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A new Coelorinchus from the western Indian Ocean with comments on the C. tokiensis group of species (Teleostei: Gadiformes: Macrouridae) PISCESTAXONOMYMORPHOLOGYDEEP-SEA BENTHIC FISHINDO-PACIFIC AbstractA new species, Coelorinchus zinjianus sp. nov., is described from the western Indian Ocean off Madagascar. In many respects, the new species is similar to C. quadricristatus but differs from that species in details of scale spinulation, mouth coloration (pale vs. dark), size of external light organ, and some other proportions. Together with C. flabellispinis and C. trunovi, these species form the flabellispinis species group, which is restricted to the northern and western Indian Ocean and is similar in most respects to the West-Pacific tokiensis group, but differs in the size and shape of the terminal snout scute (long and pointed, diamond-shaped vs. small and blunt) and apparently attaining a smaller adult size (< 45–55 cm TL vs. > 80–90 cm TL, depending on the species).
mapress.com/zt/article/view/zootaxa.5301.1.7
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Phenacogaster lucenae • Molecular Species Delimitation and Description of A New Species of Phenacogaster (Characiformes: Characidae) from the southern Amazon Basin
Phenacogaster lucenae
Souza, Mattox, Vita, Ochoa, Melo & Oliveira, 2023
DOI: 10.3897/zookeys.1164.102436
Abstract
Phenacogaster is the most species-rich genus of the subfamily Characinae with 23 valid species broadly distributed in riverine systems of South America. Despite the taxonomic diversity of the genus, little has been advanced about its molecular diversity. A recent molecular phylogeny indicated the presence of undescribed species within Phenacogaster that is formally described here. We sampled 73 specimens of Phenacogaster and sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene in order to undertake species delimitation analyses and evaluate their intra- and interspecific genetic diversity. The results show the presence of 14 species, 13 of which are valid and one undescribed. The new species is known from the tributaries of the Xingu basin, the Rio das Mortes of the Araguaia basin, and the Rio Teles Pires of the Tapajós basin. It is distinguished by the incomplete lateral line, position of the humeral blotch near the pseudotympanum, and shape of the caudal-peduncle blotch. Meristic data and genetic differentiation relative to other Phenacogaster species represent strong evidence for the recognition of the new species and highlight the occurrence of an additional lineage of P. franciscoensis.
Keywords: Biodiversity, Characinae, mitochondrial DNA, Neotropical freshwater fishes, Phenacogasterini
Phenacogaster lucenae
A MZUSP 126754, holotype, 26.7 mm SL, Brazil, Pará, Novo Progresso, Xingu basin, stream affluent of Rio Curuá
B LBP 30738, paratype, 38.1 mm SL, Brazil, Mato Grosso, Primavera do Leste, Xingu basin, Rio Culuene, Córrego Xavante
C LBP 25217, paratype, 30.6 mm SL, Brazil, Pará, Altamira, Xingu basin, Rio Treze de Maio.
Phenacogaster lucenae sp. nov.
Phenacogaster sp. Xingu: Souza et al. 2022: 9, figs 3, 5
[molecular phylogeny; cited in figures also as Phenacogaster sp. Xingu].
Diagnosis: Phenacogaster lucenae is distinguished from all congeners except P. tegata (Eigenmann, 1911), P. carteri (Norman, 1934), P. napoatilis Lucena & Malabarba, 2010, and P. capitulata Lucena & Malabarba, 2010 by having an incomplete lateral line (vs. complete lateral line). It differs from P. tegata by the presence of a round or slightly longitudinal oval humeral blotch near the pseudotympanum and distant from the vertical through dorsal-fin origin (vs. humeral blotch longitudinally elongated distant from pseudotympanum, closer to vertical through dorsal-fin origin). The new species differs from P. carteri by having a humeral blotch in males and females (vs. absence of humeral blotch in both sexes) and from P. napoatilis and P. capitulata by having a humeral blotch in both sexes (vs. absence of humeral blotch in males). In addition to the incomplete lateral line (vs. complete), P. lucenae differs from P. retropinna Lucena & Malabarba, 2010 by the anal-fin origin at vertical through base of first or second dorsal-fin branched ray (vs. anal-fin origin located posteriorly to that point), and from P. ojitata Lucena & Malabarba, 2010 by the round caudal peduncle blotch slightly reaching over the middle caudal-fin rays (vs. a diamond-shaped caudal peduncle blotch and further extending over the middle caudal-fin rays).
Etymology: Phenacogaster lucenae is named in honor of Dr. Zilda Margarete Seixas de Lucena, an eminent ichthyologist who has significantly contributed to our knowledge of Phenacogaster taxonomy. A noun in genitive case.
Camila S. Souza, George M. T. Mattox, George Vita, Luz E. Ochoa, Bruno F. Melo and Claudio Oliveira. 2023. Molecular Species Delimitation and Description of A New Species of Phenacogaster (Teleostei, Characidae) from the southern Amazon Basin. ZooKeys. 1164: 1-21. DOI: 10.3897/zookeys.1164.102436
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Phenacogaster lucenae
Souza, Mattox, Vita, Ochoa, Melo & Oliveira, 2023
DOI: 10.3897/zookeys.1164.102436
Abstract
Phenacogaster is the most species-rich genus of the subfamily Characinae with 23 valid species broadly distributed in riverine systems of South America. Despite the taxonomic diversity of the genus, little has been advanced about its molecular diversity. A recent molecular phylogeny indicated the presence of undescribed species within Phenacogaster that is formally described here. We sampled 73 specimens of Phenacogaster and sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene in order to undertake species delimitation analyses and evaluate their intra- and interspecific genetic diversity. The results show the presence of 14 species, 13 of which are valid and one undescribed. The new species is known from the tributaries of the Xingu basin, the Rio das Mortes of the Araguaia basin, and the Rio Teles Pires of the Tapajós basin. It is distinguished by the incomplete lateral line, position of the humeral blotch near the pseudotympanum, and shape of the caudal-peduncle blotch. Meristic data and genetic differentiation relative to other Phenacogaster species represent strong evidence for the recognition of the new species and highlight the occurrence of an additional lineage of P. franciscoensis.
Keywords: Biodiversity, Characinae, mitochondrial DNA, Neotropical freshwater fishes, Phenacogasterini
Phenacogaster lucenae
A MZUSP 126754, holotype, 26.7 mm SL, Brazil, Pará, Novo Progresso, Xingu basin, stream affluent of Rio Curuá
B LBP 30738, paratype, 38.1 mm SL, Brazil, Mato Grosso, Primavera do Leste, Xingu basin, Rio Culuene, Córrego Xavante
C LBP 25217, paratype, 30.6 mm SL, Brazil, Pará, Altamira, Xingu basin, Rio Treze de Maio.
Phenacogaster lucenae sp. nov.
Phenacogaster sp. Xingu: Souza et al. 2022: 9, figs 3, 5
[molecular phylogeny; cited in figures also as Phenacogaster sp. Xingu].
Diagnosis: Phenacogaster lucenae is distinguished from all congeners except P. tegata (Eigenmann, 1911), P. carteri (Norman, 1934), P. napoatilis Lucena & Malabarba, 2010, and P. capitulata Lucena & Malabarba, 2010 by having an incomplete lateral line (vs. complete lateral line). It differs from P. tegata by the presence of a round or slightly longitudinal oval humeral blotch near the pseudotympanum and distant from the vertical through dorsal-fin origin (vs. humeral blotch longitudinally elongated distant from pseudotympanum, closer to vertical through dorsal-fin origin). The new species differs from P. carteri by having a humeral blotch in males and females (vs. absence of humeral blotch in both sexes) and from P. napoatilis and P. capitulata by having a humeral blotch in both sexes (vs. absence of humeral blotch in males). In addition to the incomplete lateral line (vs. complete), P. lucenae differs from P. retropinna Lucena & Malabarba, 2010 by the anal-fin origin at vertical through base of first or second dorsal-fin branched ray (vs. anal-fin origin located posteriorly to that point), and from P. ojitata Lucena & Malabarba, 2010 by the round caudal peduncle blotch slightly reaching over the middle caudal-fin rays (vs. a diamond-shaped caudal peduncle blotch and further extending over the middle caudal-fin rays).
Etymology: Phenacogaster lucenae is named in honor of Dr. Zilda Margarete Seixas de Lucena, an eminent ichthyologist who has significantly contributed to our knowledge of Phenacogaster taxonomy. A noun in genitive case.
Camila S. Souza, George M. T. Mattox, George Vita, Luz E. Ochoa, Bruno F. Melo and Claudio Oliveira. 2023. Molecular Species Delimitation and Description of A New Species of Phenacogaster (Teleostei, Characidae) from the southern Amazon Basin. ZooKeys. 1164: 1-21. DOI: 10.3897/zookeys.1164.102436
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Kryptolebias genome of three species
IntroductionKryptolebias is a killifish genus (family Rivulidae) composed of seven currently valid species (Berbel-Filho et al. 2022), although the number of species in the genus is likely to change as some taxonomic debates are still ongoing (Berbel-Filho et al. 2022; Huber 2016). Phylogenetic analyses have indicated the presence of two distinct monophyletic clades within Kryptolebias, one of them composed of narrowly distributed freshwater species living in temporary streams and pools in South America: K. campelloi (Costa 1990) from North Brazil; K. sepia Vermeulen & Hrbek 2005 from Suriname; K. gracilis Costa 2007, and K. brasiliensis (Valenciennes 1821) from Southeast Brazil. The other clade is composed of three species living in mangrove forests along the tropical and subtropical western Atlantic basin, the ‘mangrove killifish clade’: K. marmoratus (Poey 1880), K. hermaphroditus sensu Costa 2011, and K. ocellatus (sensu Costa 2011) (Berbel-Filho et al. 2022; Costa, Lima, and Bartolette 2010; Murphy, Thomerson, and Collier 1999; Tatarenkov et al. 2009, 2017).
Kryptolebias is a remarkable genus in many aspects. For instance, K. marmoratus and K. hermaphroditus sensu Costa 2011 are the only two vertebrates known to be capable of self-fertilization (Berbel-Filho et al. 2022), whereas K. ocellatus (sensu Costa 2011) is a hermaphroditic but obligate outcrossing species (Berbel-Filho et al. 2020). This variation in mating systems makes Kryptolebias a unique vertebrate system for investigating the genomic, physiological, and behavioral changes involved in the transition from outcrossing to selfing. In addition, K. marmoratus, the most well-studied Kryptolebias species, is considered a highly amphibious fish (Turko, Rossi, and Wright 2021), with extreme physiological and behavioral adaptations to live out of water, in some cases for months (Taylor 1990). The amphibious nature of K. marmoratus is also likely to be valid for other Kryptolebias species, providing unique opportunities for studying the phenotypic and genomic changes involved in the transition from aquatic to terrestrial habitats.
To avoid long-term taxonomic confusion, we would like to provide some background on the taxonomic status of K. ocellatus (Sensu Costa 2011), whose genome was sequenced here. Due to morphological similarities and syntopy between species, the taxonomic status of the mangrove killifish clade has been historically confusing, particularly in Southeast Brazil. Briefly, Rivulus ocellatus was initially described by Hensel (1868) using a single specimen from Rio de Janeiro, Brazil. Later, Seegers (1984) suggested the existence of two syntopic species in Rio de Janeiro: the hermaphroditic R. ocellatus as in Hensel (1868), and a yet undescribed species composed of hermaphrodites and males, named R. caudomarginatus. After taxonomic revision of the family Rivulidae, Costa (2004) reclassified some previously known Rivulus species (Rivulus brasiliensis, R. campelloi, R. caudomarginatus, R. ocellatus, and R. marmoratus) into a new genus called Kryptolebias. After morphological evaluation of the K. ocellatus holotype by Costa (2011) argued that the species originally described by Hensel as K. ocellatus was in fact K. caudomarginatus (as in Seegers (1984)). Therefore, K. caudomarginatus has become a junior synonym for K. ocellatus. The other syntopic species composed of selfing hermaphrodites was then named as K. hermaphroditus (Costa 2011). However, discussions on the taxonomic nomenclature of these mangrove killifish species are still ongoing (Huber 2016). This taxonomic connudrum is likely to be fully resolved only when the genetic data of the formalin-fixed K. ocellatus holotype, initially described by Hensel (1868), is available. For the genome generated here, we used the currently valid taxonomic classification, with the selfing species occurring from the Caribbean to Southeast Brazil, named K. hermaphroditus sensu Costa 2011, and the androdioceous outcrossing from South and Southeast Brazil, K. ocellatus (sensu Costa 2011) (Berbel-Filho et al. 2020, 2022).
Here we provide whole genome sequencing data for the mangrove killifish K. ocellatus (sensu Costa 2011) (Fig. 1a), and two freshwater Kryptolebias species: K. brasiliensis and K. gracilis (Fig. 1b and c, respectively). Although Kryptolebias ocellatus has no current classification of its conservation status, K. brasiliensis and K. gracilis are categorized as endangered and critically endangered species, respectively, by the Brazilian list of threatened fish species (MMA 2022).
biodiversitygenomes.scholasticahq.com/article/77448-the-complete-genome-sequences-of-three-species-from-the-killifish-genus-kryptolebias-rivulidae-cyprinodontiformes
biodiversitygenomes.scholasticahq.com/article/77448-the-complete-genome-sequences-of-three-species-from-the-killifish-genus-kryptolebias-rivulidae-cyprinodontiformes
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Encheloclarias kelioides)
Fish species thought extinct discovered in small Singapore swamp, many miles from where it was last seen
- The last time the Keli bladefin catfish (Encheloclarias kelioides) was seen was 1993, approximately 300 km from the site of this discovery.
- The finding extends the range of the species considerably, and highlights the importance of small remnant forest fragments as harbours for biodiversity.
- The discovery confirms the species as currently the only freshwater fish species in Singapore listed globally as Critically Endangered on the IUCN Red List.
© National Parks Board
Until recently……the air-breathing catfish (Encheloclarias kelioides) had only ever been seen and recorded twice: once way back in 1934, and again in 1993. With much of the species’ eastern Peninsular Malaysia peat swamp habitats having been drained to make way for palm oil plantations, the catfish was listed as Critically Endangered (Possibly Extinct) in 1996. But in August 2022, researchers were baffled when a specimen turned up in a trap set by students researching crabs in Singapore’s Nee Soon Swamp Forest. Incredibly, it was the elusive Encheloclarias kelioides, discovered for the first time many miles from where it had previously been recorded.
Dr Tan Heok Hui, a Singaporean ichthyologist based at the Lee Kong Chian Natural History Museum, Faculty of Science, National University of Singapore, was one of the researchers who confirmed the identity of this surprising discovery. He said, “Encheloclarias has never been recorded in Singapore, and Encheloclarias kelioides is a really rare species that has previously only been recorded from peat swamp habitat. Singapore doesn’t have real peat swamp – the specimen was found in more like a mature acid swamp forest – so the discovery is pretty remarkable. It has rewritten our knowledge of Encheloclarias. When it first made its way to me, I thought, you’ve got to be kidding, this has to be a practical joke!”.
The Encheloclarias kelioides individuals caught were accidental bycatch from traps that had been set by Tan Zhi Wan, Research Assistant at the Lee Kong Chian Natural History Museum and Elysia Toh, Research Associate at Yale-NUS College as part of their research into semi- terrestrial crabs. Nobody was actively looking for Encheloclarias, and it was just pure luck that they recognised them as being different from any catfish known from that region. They had no permit to take the fish from the Nee Soon reserve, but before they returned the individuals to the water, they took photos to send to the experts.
© Tan Heok Hui
Dr Tan was one of the ichthyologists who received the photos……and he immediately recognised the images as being Encheloclarias. A month later, Dr Tan, Tan Zhi Wan and Elysia Toh visited the same area of the Nee Soon Swamp Forest where the individuals were previously found, set similar traps and left them overnight. When they checked the traps the next day, the fish was there. Dr Tan said, “It gave me the impression that we were really lucky”.
The discovery represents a range extension for the species, which was previously understood to be restricted to peat swamps in eastern Peninsular Malaysia and possibly central Sumatra (the specimen found there has not been confirmed as Encheloclarias kelioides) (Tan, Zhi Wan et al, 2023).
The Bebar drainage where the species was spotted……in 1993 is around 300 km from Nee Soon. So how did the species end up 300 km from where it was last seen three decades ago? Over many millennia, Tan said, “Southeast Asia experienced floodings and drying outs from rising and lowering of the sea level. The Gulf of Thailand actually once drained to one major river, and Singapore and part of Malaysia would have been part of that. They were once connected”.
Finding Encheloclarias kelioides in the Nee Soon Swamp Forest is significant for a number of reasons. Firstly, it proves that the species is not extinct. Secondly, this represents a range extension for the species of hundreds of kilometres. And thirdly, it helps confirm the Nee Soon Swamp Forest as an area of global conservation importance. While small, at approximately 5km 2 , it is the last remaining fragment of primary freshwater swamp forest in Singapore and is lush with biodiversity, harbouring more than half of the native freshwater fish species in Singapore, with some species being restricted only to this forest (Ho et al., 2016; Li et al., 2016; Tan et al., 2020). Furthermore, it is protected under Singapore law: with the public needing a permit to enter and no threat of development, it has become a secure refuge for wildlife.
Given that species of the genus Encheloclarias are acid-water specialists, this discovery highlights the significance of the Nee Soon Swamp Forest and the importance of conserving this habitat as a stronghold of uncommon and stenotopic freshwater fauna in Singapore (Ng & Lim, 1992; Cai et al., 2018; Clews et al., 2018;).
© Tan Zhi Wan
According to Dr. Tan……to ensure Encheloclarias kelioides is protected from extinction, Singapore needs to keep doing what it has been doing, i.e. keep Nee Soon swamp protected. And there should be, “Proper baseline surveys and monitoring programmes by local experts, proper and fair legislation, and enforcements if people break the laws”.
He conceded that conserving the Encheloclarias genus could be a bit more tricky: “When wetlands are protected, they are never protected for the freshwater inhabitants but for birds mostly, and enigmatic animals like orangutans. Seldom fishes, which is sad. To get funding to do these surveys is not easy, and most of the local conservationists are not really trained to recognise the fish. Also, I’ve been to protected areas where you can catch fish and eat them. You can’t catch a bird or a mammal but there are different standards with fish, which is often viewed as a cheap source of protein”.
In light of the new discovery, Dr Tan together with the rest of the team, including Associate Professor Darren Yeo of the Lee Kong Chian Natural History Museum and Department of Biological Sciences, National University of Singapore, Dr Cai Yixiong, Senior Manager at the National Biodiversity Centre, National Parks Board (NParks), Tan Zhi Wan and Elysia Toh recommend the species’ IUCN Red List assessment status to be revised to Critically Endangered and consider its national conservation status in Singapore to be Critically Endangered.
The discovery occurred a few months before……the planned release of an ‘The Strategic Framework to Accelerate Urgent Conservation Action for ASAP Freshwater Fishes in Southeast Asia’, a collaboration between the IUCN Species Survival Commission Asian Species Action Partnership, SHOAL, and Mandai Nature, that provides a strategic framework to accelerate urgent conservation action for the most threatened freshwater fish species in Asia. The Strategic Framework is due for release this spring.
The study on the discovery of several specimens of Encheloclarias kelioides in Nee Soon Swamp Forest was co-authored by the National University of Singapore (NUS) and NParks, which is the lead agency for greenery, biodiversity conservation, and wildlife and animal health, welfare and management in Singapore, and responsible for enhancing and managing the urban ecosystems there.
© Tan Heok Hui
In a statement…Mr Ryan Lee, Group Director, National Biodiversity Centre, NParks, said, “The presence of these specimens in Nee Soon Swamp Forest within the Central Catchment Nature Reserve suggests the importance of small forest fragments as habitats for biodiversity including cryptic species. The Central Catchment Nature Reserve is one of four gazetted nature reserves in Singapore, which are legally protected areas of rich biodiversity that are representative sites of key indigenous ecosystems. Hence, there are restrictions on the activities that can be carried out in these areas, as well as access to certain sites, to safeguard the native flora and fauna.
“As such, minimal change to the existing freshwater swamp conditions are possible factors that could have allowed Encheloclarias kelioides to survive. It is reasonable to expect that more freshwater fish species may be discovered here in the future.
“NParks will continue to work with researchers to better understand the abundance and distribution range of Encheloclarias kelioides in Singapore, as well as the role these native catfish play in the freshwater ecosystem. This discovery highlights the significance of Nee Soon Swamp Forest as a stronghold of uncommon and specialised freshwater fauna in Singapore. As part of our efforts under the Nature Conservation Masterplan, NParks will continue to conserve Singapore’s key habitats, through the safeguarding and strengthening of Singapore’s core biodiversity areas, including our nature reserves. In addition, we will continue to conserve more native plant and animal species. These efforts will continue to allow our native biodiversity to thrive, allowing us to achieve our vision of becoming a City in Nature”.
The Lee Kong Chian Natural History Museum is currently celebrating its eighth birthday, and Encheloclarias had been displayed in the museum as part of the anniversary celebrations.
The species does not currently have a common name. Dr Tan suggested it could be called the Keli bladefin catfish: bladefin catfish is the common name for all Encheloclarias, and in Malay, Clarias catfish are known as Ikan Keli.
shoalconservation.org/keli-bladefin-catfish/
=========================
Melanostomias dio • A New Species of the Dragonfish Genus Melanostomias (Stomiiformes: Stomiidae: Melanostomiinae) from the Western Tropical Atlantic
Melanostomias dio
Villarins, Fischer, Prokofiev & Mincarone, 2023
DOI: 10.1643/i2022082
twitter.com/IchsAndHerps
Abstract
A new species of the scaleless black dragonfish genus Melanostomias is described based on a single specimen (180 mm SL) collected off the northern Fernando de Noronha Archipelago (Brazil), western Tropical Atlantic. It differs from its congeners in having a unique barbel morphology, which ends in a bulb with two opposite slender terminal appendages. In addition, the occurrences of Melanostomias melanops and M. valdiviae are confirmed in Brazilian waters based on examination of new material. An overview analysis of the distribution and meristic variation of the species within the genus is also provided.
Melanostomias dio, holotype, NPM 4606, 180 mm SL,
off northern Fernando de Noronha Archipelago, Brazil.
Scale bar = 10 mm.
Melanostomias dio, new species
Horns-up Dragonfish
Etymology.--The specific name honors the late Ronald James Padavona, professionally known as Ronnie James Dio, one of the greatest and most influential heavy metal vocalists of all time. Among his many contributions to the metal culture, Dio popularized the hand gesture commonly referred to as horns up, which resembles the shape of the terminal bulb on the chin barbel of the new species.
Bárbara Teixeira Villarins, Luciano Gomes Fischer, Artem Mikhailovich Prokofiev and Michael Maia Mincarone. 2023. A New Species of the Dragonfish Genus Melanostomias (Stomiidae: Melanostomiinae) from the Western Tropical Atlantic. Ichthyology & Herpetology. 111(2); 254-263. DOI: 10.1643/i2022082
twitter.com/IchsAndHerps/status/1660652365320531971
=========================
Melanostomias dio
Villarins, Fischer, Prokofiev & Mincarone, 2023
DOI: 10.1643/i2022082
twitter.com/IchsAndHerps
Abstract
A new species of the scaleless black dragonfish genus Melanostomias is described based on a single specimen (180 mm SL) collected off the northern Fernando de Noronha Archipelago (Brazil), western Tropical Atlantic. It differs from its congeners in having a unique barbel morphology, which ends in a bulb with two opposite slender terminal appendages. In addition, the occurrences of Melanostomias melanops and M. valdiviae are confirmed in Brazilian waters based on examination of new material. An overview analysis of the distribution and meristic variation of the species within the genus is also provided.
Melanostomias dio, holotype, NPM 4606, 180 mm SL,
off northern Fernando de Noronha Archipelago, Brazil.
Scale bar = 10 mm.
Melanostomias dio, new species
Horns-up Dragonfish
Etymology.--The specific name honors the late Ronald James Padavona, professionally known as Ronnie James Dio, one of the greatest and most influential heavy metal vocalists of all time. Among his many contributions to the metal culture, Dio popularized the hand gesture commonly referred to as horns up, which resembles the shape of the terminal bulb on the chin barbel of the new species.
Bárbara Teixeira Villarins, Luciano Gomes Fischer, Artem Mikhailovich Prokofiev and Michael Maia Mincarone. 2023. A New Species of the Dragonfish Genus Melanostomias (Stomiidae: Melanostomiinae) from the Western Tropical Atlantic. Ichthyology & Herpetology. 111(2); 254-263. DOI: 10.1643/i2022082
twitter.com/IchsAndHerps/status/1660652365320531971
=========================
Listrura gyrinura sp. nov.
http://zoobank.org/act: F68F2A3E-B5F7-418E-BFA6-EA6752BAB543
( Figures 1–3a–c View Figure 1 View Figure 2 View Figure 3 ; Table 1 View Table 1 )
Holotype
UFRJ 6927 , 39.9 mm SL; Brazil: Santa Catarina State: Municipality of Paulo Lopes: village of Sertão do Campo : stream tributary to Rio da Madre , 27.920°S, 48.692°W; C.R.M. Feltrin and F.R. Colonetti, 10 July 2020.
GoogleMapsParatypes
UFRJ 6928, 10, 27.6–41.6 mm SL; UFRJ 6929, 4 (C&S), 29.7–38.4 mm SL; CICCAA 02658, 5, 29.7–37.0 mm SL; collected with holotype.
Diagnosis
Listrura gyrinura is distinguished from all congeners, except L. depinnai and L. urussanga , by having a deep caudal peduncle,deeper than the preanal region of the body, as the result of an expanded skin fold involving procurrent caudal-fin rays (vs caudal peduncle slender, its depth about equal to preanal depth). Listrura gyrinura is distinguished from L. depinnai and L. urussanga by having more vertebrae (51 or 52 vs 45 or 46 in L. depinnai and 48 or 49 in L. urussanga ), absence of a process on the dorsal surface of the autopalatine articular facet for the mesethmoid (vs presence),and by the mesethmoid cornu being slightly posteriorly folded (vs straight). Listrura gyrinura also differs from L. depinnai by the presence of a dorsal fin (vs absence), and from L. urussanga by having the dorsal-fin origin at a vertical between the centra of the 31st to 33rd vertebrae (vs between centra of the 29th and 30th vertebrae), anal-fin origin at a vertical between the centra of the 32nd and 33rd vertebrae (vs between the centra of the 30th and 31st vertebrae), absence of a ventral projection on the hyomandibula articular facet for the opercle (vs presence), and a shorter parhypural posterior process, its length about half or slightly less of the length between the anterior margin of the parurohyal head and the proximal limit of the posterior process (vs about equal to that length). Listrura gyrinura is also distinguished from L. boticario and L. camposae by having more ventral procurrent caudal-fin rays (31–36, vs 28 in L. boticario and 26–28 in L. camposae ).
Description
Morphometric data appear in Table 1 View Table 1 . Body slender, subcylindrical anteriorly, compressed posteriorly. Greatest body depth approximately at middle region of caudal peduncle. Dorsal and ventral profiles slightly convex, slightly expanded on caudal peduncle. Skin papillae minute. Anus and urogenital papilla slightly anterior to anal fin base. Head trapezoidal in dorsal view. Anterior profile of head straight in dorsal view. Eye small, dorsally positioned in head, just anterior to midway between snout and posterior limit of head. Posterior nostril located nearer to orbit than to anterior nostril. Barbels long, reaching basal portion of first pectoral-fin ray. Mouth subterminal. Jaw teeth pointed, arranged in two rows; total premaxillary teeth 18–23, outer row 7–10, inner row 11–13; total dentary teeth 15–18, outer row 6–7, inner row 7–11. Branchial membrane attached to isthmus only at its anterior point. Branchiostegal rays 5–7.
Dorsal and anal fins minute; total dorsal-fin rays 6–8 (i–ii + V–VI), total anal-fin rays 8 (ii–iii + 5–6); dorsal-fin origin at vertical slightly posterior to anal-fin base, between centra of 31st to 33rd vertebrae; anal-fin origin at vertical through centrum of 32nd or 33rd vertebra. Pectoral fin narrow, total pectoral-fin rays 3 (III), first ray well developed, second and third rays rudimentary, second ray half first ray length or less, third ray slightly shorter than second ray. Pelvic fin and girdle absent. Caudal fin spatula-shaped, narrowing posteriorly; dorsal and ventral procurrent rays anteriorly extending to area close to dorsal- and anal-fin base, respectively; total principal caudal-fin rays 12 or 13 (I–II + 7–9 + II–III), total dorsal procurrent rays 33–38 (xxxii–xxxvii + I–II), total ventral procurrent rays 31–36 (xxx–xxxiv + I–III). Vertebrae 51–52. Ribs 2 or 3. Single dorsal hypural plate, corresponding to hypurals 3–5; single ventral hypural plate corresponding to hypurals 1–2 and parhypural.
Latero-sensory system
Cephalic sensory canal minute, restricted to short postorbital canal with 2 pores just above opercular patch of odontodes, connected to short lateral line of body, with 1 pore just posterior to pectoral-fin base.
Osteology ( Figure 3a–c View Figure 3 )
Mesethmoid thin, posteriorly widening, with distinctive lateral expansion; cornu narrow and slightly posteriorly folded. Antorbital pentagonal; sesamoid supraorbital minute. Premaxilla sub-triangular in dorsal view, with narrow lateral extremity. Maxilla moderate in length, slightly longer than premaxilla length. Autopalatine sub-rectangular in dorsal view, compact, lateral and medial margins slightly concave; autopalatine posterolateral process minute, with narrow process dorso-medially directed; articular facet for mesethmoid wide, without distinctive dorsal process. Metapterygoid minute. Quadrate slender, dorsal process narrow, without posterior outgrowth. Hyomandibula long, with anterior outgrowth anteriorly terminating in sharp tip; articular facet for opercle robust, without distinctive ventral expansion. Opercle slender, transverse length of odontode patch about three quarters of transverse length of interopercular odontode patch; interopercle compact, with minute postero-dorsal process; opercular odontodes 5–7, interopercular odontodes 8–10; odontodes pointed, nearly straight. Preopercle narrow and long. Parurohyal slender, lateral process narrow and pointed, latero-posteriorly directed; parurohyal head small, with prominent anterolateral paired process; middle foramen small and rounded; posterior process short, its length about half or slightly less of length between anterior margin of parurohyal head and proximal limit of posterior process.
Colouration in alcohol
Dorsum and dorsal portion of flank and head light brownish grey, with brown chromatophores irregularly arranged, often forming small irregularly shaped spots, darker on flank longitudinal midline; on head, brown chromatophores extending over base of barbels; unpigmented area below orbit. Venter and ventral portion of flank and head greyish white, often with brown chromatophores irregularly arranged on posterior region of flank, sometimes a few brown chromatophores on ventral portion of head and venter. Fins hyaline with brown chromatophores forming minute spots.
Distribution, habitat and conservation
Listrura gyrinura is only known from the type locality, a clear-water stream tributary to the Rio da Madre, a small isolated coastal river basin ( Figure 4 View Figure 4 ). It was found close to the leaf litter over gravel sediment on the stream bottom ( Figure 5a View Figure 5 ). The habitat of this species may be considered highly endangered by mining activities that use explosives. About 100 m below the type locality, the stream is highly impacted by both mining sediments and rice planting.
Etymology
From the Greek gyrinus (tadpole) and ura (tail), referring to the shape of the caudal fin and caudal peduncle of the new species, similar to that occurring in tadpoles.
==========================
http://zoobank.org/act: F68F2A3E-B5F7-418E-BFA6-EA6752BAB543
( Figures 1–3a–c View Figure 1 View Figure 2 View Figure 3 ; Table 1 View Table 1 )
Holotype
UFRJ 6927 , 39.9 mm SL; Brazil: Santa Catarina State: Municipality of Paulo Lopes: village of Sertão do Campo : stream tributary to Rio da Madre , 27.920°S, 48.692°W; C.R.M. Feltrin and F.R. Colonetti, 10 July 2020.
GoogleMapsParatypes
UFRJ 6928, 10, 27.6–41.6 mm SL; UFRJ 6929, 4 (C&S), 29.7–38.4 mm SL; CICCAA 02658, 5, 29.7–37.0 mm SL; collected with holotype.
Diagnosis
Listrura gyrinura is distinguished from all congeners, except L. depinnai and L. urussanga , by having a deep caudal peduncle,deeper than the preanal region of the body, as the result of an expanded skin fold involving procurrent caudal-fin rays (vs caudal peduncle slender, its depth about equal to preanal depth). Listrura gyrinura is distinguished from L. depinnai and L. urussanga by having more vertebrae (51 or 52 vs 45 or 46 in L. depinnai and 48 or 49 in L. urussanga ), absence of a process on the dorsal surface of the autopalatine articular facet for the mesethmoid (vs presence),and by the mesethmoid cornu being slightly posteriorly folded (vs straight). Listrura gyrinura also differs from L. depinnai by the presence of a dorsal fin (vs absence), and from L. urussanga by having the dorsal-fin origin at a vertical between the centra of the 31st to 33rd vertebrae (vs between centra of the 29th and 30th vertebrae), anal-fin origin at a vertical between the centra of the 32nd and 33rd vertebrae (vs between the centra of the 30th and 31st vertebrae), absence of a ventral projection on the hyomandibula articular facet for the opercle (vs presence), and a shorter parhypural posterior process, its length about half or slightly less of the length between the anterior margin of the parurohyal head and the proximal limit of the posterior process (vs about equal to that length). Listrura gyrinura is also distinguished from L. boticario and L. camposae by having more ventral procurrent caudal-fin rays (31–36, vs 28 in L. boticario and 26–28 in L. camposae ).
Description
Morphometric data appear in Table 1 View Table 1 . Body slender, subcylindrical anteriorly, compressed posteriorly. Greatest body depth approximately at middle region of caudal peduncle. Dorsal and ventral profiles slightly convex, slightly expanded on caudal peduncle. Skin papillae minute. Anus and urogenital papilla slightly anterior to anal fin base. Head trapezoidal in dorsal view. Anterior profile of head straight in dorsal view. Eye small, dorsally positioned in head, just anterior to midway between snout and posterior limit of head. Posterior nostril located nearer to orbit than to anterior nostril. Barbels long, reaching basal portion of first pectoral-fin ray. Mouth subterminal. Jaw teeth pointed, arranged in two rows; total premaxillary teeth 18–23, outer row 7–10, inner row 11–13; total dentary teeth 15–18, outer row 6–7, inner row 7–11. Branchial membrane attached to isthmus only at its anterior point. Branchiostegal rays 5–7.
Dorsal and anal fins minute; total dorsal-fin rays 6–8 (i–ii + V–VI), total anal-fin rays 8 (ii–iii + 5–6); dorsal-fin origin at vertical slightly posterior to anal-fin base, between centra of 31st to 33rd vertebrae; anal-fin origin at vertical through centrum of 32nd or 33rd vertebra. Pectoral fin narrow, total pectoral-fin rays 3 (III), first ray well developed, second and third rays rudimentary, second ray half first ray length or less, third ray slightly shorter than second ray. Pelvic fin and girdle absent. Caudal fin spatula-shaped, narrowing posteriorly; dorsal and ventral procurrent rays anteriorly extending to area close to dorsal- and anal-fin base, respectively; total principal caudal-fin rays 12 or 13 (I–II + 7–9 + II–III), total dorsal procurrent rays 33–38 (xxxii–xxxvii + I–II), total ventral procurrent rays 31–36 (xxx–xxxiv + I–III). Vertebrae 51–52. Ribs 2 or 3. Single dorsal hypural plate, corresponding to hypurals 3–5; single ventral hypural plate corresponding to hypurals 1–2 and parhypural.
Latero-sensory system
Cephalic sensory canal minute, restricted to short postorbital canal with 2 pores just above opercular patch of odontodes, connected to short lateral line of body, with 1 pore just posterior to pectoral-fin base.
Osteology ( Figure 3a–c View Figure 3 )
Mesethmoid thin, posteriorly widening, with distinctive lateral expansion; cornu narrow and slightly posteriorly folded. Antorbital pentagonal; sesamoid supraorbital minute. Premaxilla sub-triangular in dorsal view, with narrow lateral extremity. Maxilla moderate in length, slightly longer than premaxilla length. Autopalatine sub-rectangular in dorsal view, compact, lateral and medial margins slightly concave; autopalatine posterolateral process minute, with narrow process dorso-medially directed; articular facet for mesethmoid wide, without distinctive dorsal process. Metapterygoid minute. Quadrate slender, dorsal process narrow, without posterior outgrowth. Hyomandibula long, with anterior outgrowth anteriorly terminating in sharp tip; articular facet for opercle robust, without distinctive ventral expansion. Opercle slender, transverse length of odontode patch about three quarters of transverse length of interopercular odontode patch; interopercle compact, with minute postero-dorsal process; opercular odontodes 5–7, interopercular odontodes 8–10; odontodes pointed, nearly straight. Preopercle narrow and long. Parurohyal slender, lateral process narrow and pointed, latero-posteriorly directed; parurohyal head small, with prominent anterolateral paired process; middle foramen small and rounded; posterior process short, its length about half or slightly less of length between anterior margin of parurohyal head and proximal limit of posterior process.
Colouration in alcohol
Dorsum and dorsal portion of flank and head light brownish grey, with brown chromatophores irregularly arranged, often forming small irregularly shaped spots, darker on flank longitudinal midline; on head, brown chromatophores extending over base of barbels; unpigmented area below orbit. Venter and ventral portion of flank and head greyish white, often with brown chromatophores irregularly arranged on posterior region of flank, sometimes a few brown chromatophores on ventral portion of head and venter. Fins hyaline with brown chromatophores forming minute spots.
Distribution, habitat and conservation
Listrura gyrinura is only known from the type locality, a clear-water stream tributary to the Rio da Madre, a small isolated coastal river basin ( Figure 4 View Figure 4 ). It was found close to the leaf litter over gravel sediment on the stream bottom ( Figure 5a View Figure 5 ). The habitat of this species may be considered highly endangered by mining activities that use explosives. About 100 m below the type locality, the stream is highly impacted by both mining sediments and rice planting.
Etymology
From the Greek gyrinus (tadpole) and ura (tail), referring to the shape of the caudal fin and caudal peduncle of the new species, similar to that occurring in tadpoles.
==========================
A new species of mailed catfish of genus Rhadinoloricaria (Siluriformes: Loricariidae: Loricariinae) from Rio Negro basin, BrazilJefferson L. Crispim-Rodrigues, Maxwell J. Bernt, Brandon T. Waltz, Gabriel S. C. Silva, Ricardo C. Benine, Claudio Oliveira, Raphaël Covain, Fábio F. Roxo
First published: 11 May 2023
https://doi.org/10.1111/jfb.15402urn:lsid:zoobank.org:pub:6DF2C3BD-F256-4530-9620-482D87E980F8.
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SHAREAbstractDuring a recent collection expedition to the Rio Negro, in the state of Amazonas, Brazil, eight individuals of an unknown species were collected, with a combination of characteristics that placed the species in the genus Rhadinoloricaria. Furthermore, the presence of two autapomorphic characteristics, including numerous elongated papillae on the lower lip and unbranched barbelets on the margin of lower lip, suggests that it is a new species. From morphological and phylogenetic analyses, including the sequencing of specific genes to calculate the maximum likelihood analyses, coupled with osteological computed tomography (CT) scan analyses, the authors corroborated that the specimens represent a new species of Rhadinoloricaria, described in the present study.
==========================
First published: 11 May 2023
https://doi.org/10.1111/jfb.15402urn:lsid:zoobank.org:pub:6DF2C3BD-F256-4530-9620-482D87E980F8.
Read the full text
TOOLS
SHAREAbstractDuring a recent collection expedition to the Rio Negro, in the state of Amazonas, Brazil, eight individuals of an unknown species were collected, with a combination of characteristics that placed the species in the genus Rhadinoloricaria. Furthermore, the presence of two autapomorphic characteristics, including numerous elongated papillae on the lower lip and unbranched barbelets on the margin of lower lip, suggests that it is a new species. From morphological and phylogenetic analyses, including the sequencing of specific genes to calculate the maximum likelihood analyses, coupled with osteological computed tomography (CT) scan analyses, the authors corroborated that the specimens represent a new species of Rhadinoloricaria, described in the present study.
==========================
DOI: 10.11646/ZOOTAXA.5278.1.4
PUBLISHED: 2023-05-04
Okamejei picta sp. nov., a new rajid skate from the South China Sea (Rajiformes: Rajidae)PISCESCHONDRICHTHYESRAJIFORMESGENUS OKAMEJEITAXONOMYBIODIVERSITYAbstractA new species of Okamejei is described based on two adult males collected from deep waters in the South China Sea. The new species, Okamejei picta sp. nov., is readily distinguished from most other congeners in having densely scattered black spots on dorsal disc. Okamejei hollandi and O. mengae is quite similar to the new species by their spot patterns on dorsal disc, but the new species differs from the former by a combination of characters: a yellowish brown dorsal surface densely covered with small, circular to irregular-shaped black spots; blotches on dorsal disc indistinct; posterior ocellus absent; ventral disc white; disc length 45.0–47.7% TL; distance between cloaca to caudal-fin tip 53.6–55.1% TL; trunk centra 31; total basal radials 73–76, morphology of clasper terminal skeleton, and lacking component funnel at the clasper end.
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PUBLISHED: 2023-05-04
Okamejei picta sp. nov., a new rajid skate from the South China Sea (Rajiformes: Rajidae)PISCESCHONDRICHTHYESRAJIFORMESGENUS OKAMEJEITAXONOMYBIODIVERSITYAbstractA new species of Okamejei is described based on two adult males collected from deep waters in the South China Sea. The new species, Okamejei picta sp. nov., is readily distinguished from most other congeners in having densely scattered black spots on dorsal disc. Okamejei hollandi and O. mengae is quite similar to the new species by their spot patterns on dorsal disc, but the new species differs from the former by a combination of characters: a yellowish brown dorsal surface densely covered with small, circular to irregular-shaped black spots; blotches on dorsal disc indistinct; posterior ocellus absent; ventral disc white; disc length 45.0–47.7% TL; distance between cloaca to caudal-fin tip 53.6–55.1% TL; trunk centra 31; total basal radials 73–76, morphology of clasper terminal skeleton, and lacking component funnel at the clasper end.
==========================
Corydoras maclurei • A New Species of Corydoras (Siluriformes: Callichthyidae) from the rio Madre de Dios Basin, Peruvian Amazon, with Comments on Corydoras aeneus Identity
Corydoras maclurei
Tencatt, de Carvalho Gomes & Evers, 2023
DOI: 10.1590/1982-0224-2023-0023
Abstract
A new species of Corydoras is described from tributaries to the rio Araza, an affluent of the rio Inambari, itself a tributary to the rio Madre de Dios, rio Madeira basin in the Peruvian Amazon. The new species can be distinguished from its congeners by the following features: (I) absence of contact between the posterior process of the parieto-supraoccipital and the nuchal plate, (II) a single, large conspicuous dark brown or black blotch on anterodorsal portion of flank; blotch somewhat rounded to roughly diamond shaped, and (III) absence of dark blotches on fins. General comments on the identity of Corydoras aeneus are also provided.
Keywords: Corydoradinae; Corydoras sp. CW16; Osteology; Rio Madeira basin; Taxonomy
Corydoras maclurei, holotype, MUSM 70671, 37.0 mm SL,
Camanti District, Quispicanchi Province, Cusco Region, Peru, small stream tributary to the rio Araza, a bigger affluent of the rio Inambari, itself a tributary to the rio Madre de Dios, rio Madeira basin.
Uncatalogued aquarium specimens of Corydoras maclurei (not measured) showing variations of the color pattern in life:
specimens can variably present greyish orange (A) or reddish orange (B) ground color of body. In C, the detail of a conspicuously reddish orange dorsal fin. Anterior portion of first dorsolateral body plate typically with orange (D) or yellow (E) bright patch. Photographs (D) and (E) by Ian Fuller.
Uncatalogued aquarium specimen of Corydoras maclurei (A) showing its typical color pattern in life (lateral view),
collected in its type-locality (B), a small stream tributary to the rio Araza, rio Madre de Dios basin, rio Madeira basin in Peru.
Corydoras maclurei, new species
Diagnosis. Corydoras maclurei can be distinguished from its congeners, except for C. difluviatilis Britto & Castro, 2002, C. flaveolus Ihering, 1911, C. gladysae, C. gracilis Nijssen & Isbrücker, 1976, C. hastatus Eigenmann & Eigenmann, 1888, C. hephaestus Ohara, Tencatt & Britto, 2016, C. latus, C. melanotaenia Regan, 1912, C. micracanthus Regan, 1912, C. nanus, C. petracinii, C pygmaeus Knaack, 1966, and C. undulatus Regan, 1912, by the absence of contact between the posterior process of the parieto-supraoccipital and the nuchal plate (vs. bones in contact). The new species can be distinguished from C. difluviatilis, C. flaveolus, C. gladysae, C. gracilis, C. hastatus, C. hephaestus, C. latus, C. melanotaenia, C. micracanthus, C. nanus, C. petracinii, C pygmaeus, and C. undulatus by having just a single, large conspicuous dark brown or black blotch on anterodorsal portion of flank; ...
Etymology: Corydoras maclurei is named in honor of Robert “Rob” McLure, dear friend and renowned Corydoradinae breeder. Rob has been the main English-language reviewer of the first author’s publications, in addition to providing valuable information and live photos of several species of Corydoradinae. A genitive noun.
Luiz Fernando Caserta Tencatt, Vandergleison de Carvalho Gomes and Hans-Georg Evers. 2023. A New Species of Corydoras (Siluriformes: Callichthyidae) from the rio Madre de Dios Basin, Peruvian Amazon, with Comments on Corydoras aeneus Identity. Neotrop. ichthyol. 21 (2); DOI: 10.1590/1982-0224-2023-0023
======================= ===
Corydoras maclurei
Tencatt, de Carvalho Gomes & Evers, 2023
DOI: 10.1590/1982-0224-2023-0023
Abstract
A new species of Corydoras is described from tributaries to the rio Araza, an affluent of the rio Inambari, itself a tributary to the rio Madre de Dios, rio Madeira basin in the Peruvian Amazon. The new species can be distinguished from its congeners by the following features: (I) absence of contact between the posterior process of the parieto-supraoccipital and the nuchal plate, (II) a single, large conspicuous dark brown or black blotch on anterodorsal portion of flank; blotch somewhat rounded to roughly diamond shaped, and (III) absence of dark blotches on fins. General comments on the identity of Corydoras aeneus are also provided.
Keywords: Corydoradinae; Corydoras sp. CW16; Osteology; Rio Madeira basin; Taxonomy
Corydoras maclurei, holotype, MUSM 70671, 37.0 mm SL,
Camanti District, Quispicanchi Province, Cusco Region, Peru, small stream tributary to the rio Araza, a bigger affluent of the rio Inambari, itself a tributary to the rio Madre de Dios, rio Madeira basin.
Uncatalogued aquarium specimens of Corydoras maclurei (not measured) showing variations of the color pattern in life:
specimens can variably present greyish orange (A) or reddish orange (B) ground color of body. In C, the detail of a conspicuously reddish orange dorsal fin. Anterior portion of first dorsolateral body plate typically with orange (D) or yellow (E) bright patch. Photographs (D) and (E) by Ian Fuller.
Uncatalogued aquarium specimen of Corydoras maclurei (A) showing its typical color pattern in life (lateral view),
collected in its type-locality (B), a small stream tributary to the rio Araza, rio Madre de Dios basin, rio Madeira basin in Peru.
Corydoras maclurei, new species
Diagnosis. Corydoras maclurei can be distinguished from its congeners, except for C. difluviatilis Britto & Castro, 2002, C. flaveolus Ihering, 1911, C. gladysae, C. gracilis Nijssen & Isbrücker, 1976, C. hastatus Eigenmann & Eigenmann, 1888, C. hephaestus Ohara, Tencatt & Britto, 2016, C. latus, C. melanotaenia Regan, 1912, C. micracanthus Regan, 1912, C. nanus, C. petracinii, C pygmaeus Knaack, 1966, and C. undulatus Regan, 1912, by the absence of contact between the posterior process of the parieto-supraoccipital and the nuchal plate (vs. bones in contact). The new species can be distinguished from C. difluviatilis, C. flaveolus, C. gladysae, C. gracilis, C. hastatus, C. hephaestus, C. latus, C. melanotaenia, C. micracanthus, C. nanus, C. petracinii, C pygmaeus, and C. undulatus by having just a single, large conspicuous dark brown or black blotch on anterodorsal portion of flank; ...
Etymology: Corydoras maclurei is named in honor of Robert “Rob” McLure, dear friend and renowned Corydoradinae breeder. Rob has been the main English-language reviewer of the first author’s publications, in addition to providing valuable information and live photos of several species of Corydoradinae. A genitive noun.
Luiz Fernando Caserta Tencatt, Vandergleison de Carvalho Gomes and Hans-Georg Evers. 2023. A New Species of Corydoras (Siluriformes: Callichthyidae) from the rio Madre de Dios Basin, Peruvian Amazon, with Comments on Corydoras aeneus Identity. Neotrop. ichthyol. 21 (2); DOI: 10.1590/1982-0224-2023-0023
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A new species of barred Sternopygus (Gymnotiformes: Sternopygidae) from the Orinoco RiverKevin T. Torgersen1 , Aleidy M. Galindo-Cuervo2, Roberto E. Reis2 and James S. Albert1
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Abstract
A new species of Sternopygus is described from the Orinoco River of Venezuela using traditional methods of morphometrics and meristics, and micro-computed tomography (micro-CT) imaging for osteological analysis. The new species is readily separated from all congeners in having broad, vertical pigment bars that extend from the mid-dorsum to the ventral margin of the pterygiophores. A similar color pattern, characterized by subtle differences in the densities and sizes of chromatophores, is also present in juveniles of S. obtusirostris from the Amazon River, juveniles of S. sabaji from rivers of the Guiana Shield, and S. astrabes from clearwater and blackwater terra firme streams of lowlands around the Guiana Shield. The new species further differs from other congeners in the Orinoco basin by having a reduced humeral pigment blotch with poorly defined margins, a proportionally smaller head, a longer body cavity, a more slender body shape in lateral profile, and in having vertical pigment bars that extend ventrally to the pterygiophores (vs. pigment saddles not reaching the pterygiophores). The description of this species raises to three the number of Sternopygus species in the Orinoco basin, and to 11 the total number of Sternopygus species.
Keywords: Biodiversity, Computed tomography, Knifefish, Morphometrics, Taxonomy.
Introduction
With more than 1,000 described fish species, the Orinoco basin is one of the world’s hotspots of freshwater fish biodiversity (Lasso et al., 2004, 2011, 2016; Albert et al., 2011, 2020). Gymnotiform electric fishes (also called knifefishes) are an important component of the taxonomic and functional diversity of the Orinoco fauna (Lundberg et al., 1987; Albert, Crampton, 2005). Taxonomic knowledge of gymnotiform diversity in the Orinoco River has increased dramatically since the 1980s (e.g., Mago-Leccia, Zaret, 1978; Mago-Leccia et al., 1985, 1994; Lundberg, Stager, 1985; Lundberg, Mago-Leccia, 1986; de Santana, Crampton, 2011; Crampton et al., 2016). The results of these and other studies have more than tripled the number of described gymnotiform species known from the Orinoco basin from 20 to 65 over a period of 35 years (Machado-Allison, 1987; Maldonado-Ocampo, Albert, 2003; Van der Sleen, Albert, 2017; Peixoto, Waltz, 2017). These recent advances in our knowledge of gymnotiform species richness and species limits have improved our understanding of ecological and evolutionary processes (Marrero, Winemiller, 1993; Barbarino Duque, Winemiller, 2003; Winemiller, 2004; Lovejoy et al., 2010).
“Longtail electric fishes” of the genus Sternopygus Müller & Troschel, 1846 are widely distributed across the lowland river basins (<250 m elevation) of the humid Neotropics, from northern Argentina to Panama (Hulen et al., 2005; Waltz, Albert, 2017). Currently, 10 Sternopygus species are recognized as valid (Tab. 1; Hulen et al., 2005; Torgersen, Albert, 2022). However, differences in morphology (Albert, Fink, 1996), karyotypes (Santos Silva et al., 2008), and gene sequences (Maldonado-Ocampo, 2011) indicate that museum collections contain additional undescribed species. Only two Sternopygus species are known from the Orinoco basin: S. macrurus (Bloch & Schneider, 1801) (type locality unknown but in “Brazil”), and S. astrabes Mago-Leccia, 1994, which was described from a clearwater tributary of the upper Orinoco River. Sternopygus macrurus exhibits the broadest geographic distribution of all nominal gymnotiform species, with specimens ascribed to this species recorded from Pacific slope basins of Colombia to the Pampas of Argentina (Eigenmann, Ward, 1905; Eigenmann, Allen, 1942; Albert, Fink, 1996). Sternopygus macrurus is also thought to be among the most ecologically tolerant of all gymnotiform species, inhabiting water bodies of varying water chemistry (clearwater, blackwater, whitewater) and flow (riffles and runs) in lowland forests, seasonal floodplains, and even estuarine environments (Crampton, 1996, 1998a,b; Fernandes, 1999; Marceniuk et al., 2017). Due to its widespread distribution, unknown type locality, and conserved morphology, S. macrurus has long been a “wastebasket” taxon into which many specimens in museum collections have been ascribed.
TABLE 1 | Summary of all valid species of Sternopygus with information regarding primary type specimens and locality drainage for each species. Country of collection of primary types given in parenthesis.
Species
Holotype
Type drainage (Country)
Sternopygus aequilabiatus (Humboldt, 1805)
Whereabouts unknown
Magdalena (Colombia)
Sternopygus arenatus Eydoux & Souleyet, 1841
MNHN 0000-3809 (2 syntypes)
Guayaquil (Ecuador)
Sternopygus astrabes Mago-Leccia, 1994
MBUCV-V-14182
Orinoco (Venezuela)
Sternopygus branco Crampton, Hulen & Albert, 2004
MCP 32451
Amazonas (Brazil)
Sternopygus dariensis Meek & Hildebrand, 1913
FMNH 8949
Tuira (Panama)
Sternopygus macrurus (Bloch & Schneider, 1801)
ZMB 8701 (syntype, stuffed)
Unknown (Brazil)
Sternopygus obtusirostris Steindachner, 1881
MCZ 9413 (lectotype)
Amazonas (Brazil)
Sternopygus pejeraton Schultz, 1949
USNM 121752
Maracaibo (Venezuela)
Sternopygus sabaji Torgersen & Albert, 2022
ANSP 208090
Maroni (Suriname)
Sternopygus n. sp. (in this study)
ANSP 209718
Orinoco (Venezuela)
Sternopygus xingu Albert & Fink, 1996
MZUSP 48374
Xingu (Brazil)
Fishes ascribed to Sternopygus can be diagnosed from all other sternopygids by the following characters: (1) relatively larger gape (Mago-Leccia, 1978); (2) large branchial opening (Mago-Leccia, 1978); (3) long, evenly curved maxilla; (4) anterior process of maxilla extends as a narrow hook-like process (Lundberg, Mago-Leccia, 1986); (5) dorsal portion of ventral ethmoid elongate (Albert, Fink, 1996); (6) post-temporal fossa present between pterotic and epioccipital bones (Lundberg, Mago-Leccia, 1986); (7) gill rakers composed of three bony elements, the middle one with 3–10 small teeth (Mago-Leccia, 1978); (8) gill rakers not attached to branchial arches (Albert, Fink, 1996); (9) gap between parapophyses of second vertebra; (10) unossified post cleithrum (Albert, Fink, 1996); (11) long body cavity, with 18–30 precaudal vertebrae (Albert, Fink, 1996); (12) long anal fin with 170–340 rays, (13) unbranched anal-fin rays (Fink, Fink, 1981); (14) developmental origin of adult electric organ from both hypaxial and epaxial muscles (Unguez, Zakon, 1998; Albert, 2001); (15) absence of jamming avoidance response (Heiligenberg, 1991; Albert, 2001); (16) presence of a ‘medial cephalic fold’ (Triques, 2000), defined as a ridge of ectodermal tissue extending from the ventral limit of the opercular opening anteromedially to the branchial isthmus. Most Sternopygus species attain medium to large body sizes (40–50 cm Total Length (TL)), except the more diminutive S. astrabes which grows to about 20 cm TL. Most Sternopygus species are nocturnal predators of small animals (e.g., insect larvae, crustaceans) and occur in multiple habitats, including small streams, river margins, and deep river channels(Crampton et al., 2004a; Crampton, 2007, 2011; Brejão et al., 2013).
Most Sternopygus species share a similar color pattern with a base color composed of small, densely arranged gray chromatophores. Some species have a dark humeral blotch with variable contrast to the background coloration, and a distinctive yellow or white longitudinal stripe extending between the hypaxial and pterygiophore muscles on the posterior third of the body. These aspects of coloration are variable within and among nominal species and are sometimes absent, with some specimens ranging in color from deep black to pinkish white. At least three valid Sternopygus species possess a distinctive color pattern composed of 1–4 broad, dark vertical bars or saddles across the dorsal midline at some stage in their ontogeny: S. astrabes, S. obtusirostris Steindachner, 1881, S. sabaji Torgersen & Albert, 2022 (Fig. 1; Mago-Leccia, 1994; Crampton et al., 2004b; Torgersen, Albert, 2022). The monophyly, species limits, variation, and species richness of species with broad vertical pigment bars or saddles remains poorly understood and these topics are not addressed here.
FIGURE 1 | Four species of barred Sternopygus. A. Sternopygus astrabes, ANSP 162663 (189 mm TL); B. Sternopygus n. sp., ANSP 160357 (284 mm TL, paratype); C. Juvenile Sternopygus sabaji, ANSP 189018 (146 mm TL); D. Juvenile Sternopygus obtusirostris, INPA 15787 (180 mm TL), photo taken at night from Crampton et al. (2004b). Dark outlines added to bars/saddles in all photos for emphasis. Scale bars = 1 cm.
Here we describe a new species of barred Sternopygus from the lower Orinoco basin of Venezuela, bringingthe total number of species in the genus to 11, the number of species known in the Orinoco basin to three, the number of species in the Guiana Shield region to four, and the number of Sternopygus species possessing dark vertical bars to four.
==========================
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Abstract
A new species of Sternopygus is described from the Orinoco River of Venezuela using traditional methods of morphometrics and meristics, and micro-computed tomography (micro-CT) imaging for osteological analysis. The new species is readily separated from all congeners in having broad, vertical pigment bars that extend from the mid-dorsum to the ventral margin of the pterygiophores. A similar color pattern, characterized by subtle differences in the densities and sizes of chromatophores, is also present in juveniles of S. obtusirostris from the Amazon River, juveniles of S. sabaji from rivers of the Guiana Shield, and S. astrabes from clearwater and blackwater terra firme streams of lowlands around the Guiana Shield. The new species further differs from other congeners in the Orinoco basin by having a reduced humeral pigment blotch with poorly defined margins, a proportionally smaller head, a longer body cavity, a more slender body shape in lateral profile, and in having vertical pigment bars that extend ventrally to the pterygiophores (vs. pigment saddles not reaching the pterygiophores). The description of this species raises to three the number of Sternopygus species in the Orinoco basin, and to 11 the total number of Sternopygus species.
Keywords: Biodiversity, Computed tomography, Knifefish, Morphometrics, Taxonomy.
Introduction
With more than 1,000 described fish species, the Orinoco basin is one of the world’s hotspots of freshwater fish biodiversity (Lasso et al., 2004, 2011, 2016; Albert et al., 2011, 2020). Gymnotiform electric fishes (also called knifefishes) are an important component of the taxonomic and functional diversity of the Orinoco fauna (Lundberg et al., 1987; Albert, Crampton, 2005). Taxonomic knowledge of gymnotiform diversity in the Orinoco River has increased dramatically since the 1980s (e.g., Mago-Leccia, Zaret, 1978; Mago-Leccia et al., 1985, 1994; Lundberg, Stager, 1985; Lundberg, Mago-Leccia, 1986; de Santana, Crampton, 2011; Crampton et al., 2016). The results of these and other studies have more than tripled the number of described gymnotiform species known from the Orinoco basin from 20 to 65 over a period of 35 years (Machado-Allison, 1987; Maldonado-Ocampo, Albert, 2003; Van der Sleen, Albert, 2017; Peixoto, Waltz, 2017). These recent advances in our knowledge of gymnotiform species richness and species limits have improved our understanding of ecological and evolutionary processes (Marrero, Winemiller, 1993; Barbarino Duque, Winemiller, 2003; Winemiller, 2004; Lovejoy et al., 2010).
“Longtail electric fishes” of the genus Sternopygus Müller & Troschel, 1846 are widely distributed across the lowland river basins (<250 m elevation) of the humid Neotropics, from northern Argentina to Panama (Hulen et al., 2005; Waltz, Albert, 2017). Currently, 10 Sternopygus species are recognized as valid (Tab. 1; Hulen et al., 2005; Torgersen, Albert, 2022). However, differences in morphology (Albert, Fink, 1996), karyotypes (Santos Silva et al., 2008), and gene sequences (Maldonado-Ocampo, 2011) indicate that museum collections contain additional undescribed species. Only two Sternopygus species are known from the Orinoco basin: S. macrurus (Bloch & Schneider, 1801) (type locality unknown but in “Brazil”), and S. astrabes Mago-Leccia, 1994, which was described from a clearwater tributary of the upper Orinoco River. Sternopygus macrurus exhibits the broadest geographic distribution of all nominal gymnotiform species, with specimens ascribed to this species recorded from Pacific slope basins of Colombia to the Pampas of Argentina (Eigenmann, Ward, 1905; Eigenmann, Allen, 1942; Albert, Fink, 1996). Sternopygus macrurus is also thought to be among the most ecologically tolerant of all gymnotiform species, inhabiting water bodies of varying water chemistry (clearwater, blackwater, whitewater) and flow (riffles and runs) in lowland forests, seasonal floodplains, and even estuarine environments (Crampton, 1996, 1998a,b; Fernandes, 1999; Marceniuk et al., 2017). Due to its widespread distribution, unknown type locality, and conserved morphology, S. macrurus has long been a “wastebasket” taxon into which many specimens in museum collections have been ascribed.
TABLE 1 | Summary of all valid species of Sternopygus with information regarding primary type specimens and locality drainage for each species. Country of collection of primary types given in parenthesis.
Species
Holotype
Type drainage (Country)
Sternopygus aequilabiatus (Humboldt, 1805)
Whereabouts unknown
Magdalena (Colombia)
Sternopygus arenatus Eydoux & Souleyet, 1841
MNHN 0000-3809 (2 syntypes)
Guayaquil (Ecuador)
Sternopygus astrabes Mago-Leccia, 1994
MBUCV-V-14182
Orinoco (Venezuela)
Sternopygus branco Crampton, Hulen & Albert, 2004
MCP 32451
Amazonas (Brazil)
Sternopygus dariensis Meek & Hildebrand, 1913
FMNH 8949
Tuira (Panama)
Sternopygus macrurus (Bloch & Schneider, 1801)
ZMB 8701 (syntype, stuffed)
Unknown (Brazil)
Sternopygus obtusirostris Steindachner, 1881
MCZ 9413 (lectotype)
Amazonas (Brazil)
Sternopygus pejeraton Schultz, 1949
USNM 121752
Maracaibo (Venezuela)
Sternopygus sabaji Torgersen & Albert, 2022
ANSP 208090
Maroni (Suriname)
Sternopygus n. sp. (in this study)
ANSP 209718
Orinoco (Venezuela)
Sternopygus xingu Albert & Fink, 1996
MZUSP 48374
Xingu (Brazil)
Fishes ascribed to Sternopygus can be diagnosed from all other sternopygids by the following characters: (1) relatively larger gape (Mago-Leccia, 1978); (2) large branchial opening (Mago-Leccia, 1978); (3) long, evenly curved maxilla; (4) anterior process of maxilla extends as a narrow hook-like process (Lundberg, Mago-Leccia, 1986); (5) dorsal portion of ventral ethmoid elongate (Albert, Fink, 1996); (6) post-temporal fossa present between pterotic and epioccipital bones (Lundberg, Mago-Leccia, 1986); (7) gill rakers composed of three bony elements, the middle one with 3–10 small teeth (Mago-Leccia, 1978); (8) gill rakers not attached to branchial arches (Albert, Fink, 1996); (9) gap between parapophyses of second vertebra; (10) unossified post cleithrum (Albert, Fink, 1996); (11) long body cavity, with 18–30 precaudal vertebrae (Albert, Fink, 1996); (12) long anal fin with 170–340 rays, (13) unbranched anal-fin rays (Fink, Fink, 1981); (14) developmental origin of adult electric organ from both hypaxial and epaxial muscles (Unguez, Zakon, 1998; Albert, 2001); (15) absence of jamming avoidance response (Heiligenberg, 1991; Albert, 2001); (16) presence of a ‘medial cephalic fold’ (Triques, 2000), defined as a ridge of ectodermal tissue extending from the ventral limit of the opercular opening anteromedially to the branchial isthmus. Most Sternopygus species attain medium to large body sizes (40–50 cm Total Length (TL)), except the more diminutive S. astrabes which grows to about 20 cm TL. Most Sternopygus species are nocturnal predators of small animals (e.g., insect larvae, crustaceans) and occur in multiple habitats, including small streams, river margins, and deep river channels(Crampton et al., 2004a; Crampton, 2007, 2011; Brejão et al., 2013).
Most Sternopygus species share a similar color pattern with a base color composed of small, densely arranged gray chromatophores. Some species have a dark humeral blotch with variable contrast to the background coloration, and a distinctive yellow or white longitudinal stripe extending between the hypaxial and pterygiophore muscles on the posterior third of the body. These aspects of coloration are variable within and among nominal species and are sometimes absent, with some specimens ranging in color from deep black to pinkish white. At least three valid Sternopygus species possess a distinctive color pattern composed of 1–4 broad, dark vertical bars or saddles across the dorsal midline at some stage in their ontogeny: S. astrabes, S. obtusirostris Steindachner, 1881, S. sabaji Torgersen & Albert, 2022 (Fig. 1; Mago-Leccia, 1994; Crampton et al., 2004b; Torgersen, Albert, 2022). The monophyly, species limits, variation, and species richness of species with broad vertical pigment bars or saddles remains poorly understood and these topics are not addressed here.
FIGURE 1 | Four species of barred Sternopygus. A. Sternopygus astrabes, ANSP 162663 (189 mm TL); B. Sternopygus n. sp., ANSP 160357 (284 mm TL, paratype); C. Juvenile Sternopygus sabaji, ANSP 189018 (146 mm TL); D. Juvenile Sternopygus obtusirostris, INPA 15787 (180 mm TL), photo taken at night from Crampton et al. (2004b). Dark outlines added to bars/saddles in all photos for emphasis. Scale bars = 1 cm.
Here we describe a new species of barred Sternopygus from the lower Orinoco basin of Venezuela, bringingthe total number of species in the genus to 11, the number of species known in the Orinoco basin to three, the number of species in the Guiana Shield region to four, and the number of Sternopygus species possessing dark vertical bars to four.
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Original Article • Neotrop. ichthyol. 21 (1) • 2023 • https://doi.org/10.1590/1982-0224-2022-0097 COPYOriginal Article • Neotrop. ichthyol. 21 (1) • 2023 • https://doi.org/10.1590/1982-0224-2022-0097 COPY
New species of Farlowella (Siluriformes: Loricariidae) from the rio Tapajós basin, Pará, Brazil
Manuela DopazoWolmar B. WosiackiMarcelo R. BrittoABOUT THE AUTHORS
Keywords:
Amazon; Armored catfish; Biodiversity; Loricariinae; Taxonomy
ResumoUma nova espécie de cascudo-graveto Farlowella é descrita de pequenos igarapés do baixo rio Tapajós, no Estado do Pará, norte do Brasil. A nova espécie é distinta de todas as suas congêneres por uma região gular nua (vs. região gular com placas) e de muitas congêneres pela presença de cinco fileiras de placas laterais na região anterior do corpo (vs. quatro). A nova espécie apresenta variação na série de placas abdominais e é feita uma discussão sobre a variação das placas abdominais dentro de Farlowella e comentários sobre caracteres sinapomórficos em Farlowellini.
Palavras-chave:
Amazônia; Biodiversidade; Cascudo; Loricariinae; Taxonomia
INTRODUCTIONThe genus FarlowellaEigenmann & Eigenmann, 1889 is a component of the freshwater fish fauna of the Neotropics. With 32 valid species, Farlowella is the second-most species-rich genus of Loricariinae, a sub-family comprised of 262 valid species in 31 genera (Delgadillo et al., 2021; Londoño-Burbano, Reis, 2021; Fricke et al., 2023). Farlowella representatives are widely distributed in the main cis-Andean South America river drainages and trans-Andean Maracaibo and Magdalena river basins (Terán et al., 2019). They are easily distinguished by having a pronounced rostrum, a thin, elongated, brown body with two longitudinal bands that extend from the tip of the rostrum to the caudal peduncle (Covain, Fisch-Muller, 2007), resembling dry twigs or sticks, which justifies the popular name stick catfishes.
The first taxonomic study was the description of the genus Acestra by Kner, (1853), with the first species described: Acestra acus and A. oxyrryncha, but without designating the type species of the genus, until A. acus was determined by Bleeker, (1862). However, Acestra was already occupied in Hemiptera (Dallas, 1852) and the name Farlowella was then replaced by Eigenmann, Eigenmann, (1889). From the end of the 19th century, several species were described, totaling 37 names that remained for almost a century, when Retzer, Page (1996) revised the genus based on characters of external morphology. This was the last revision of its species, as well as the first exclusive hypothesis of the phylogenetic relationships of the genus. In that study, the authors performed a phylogenetic analysis with morphological data including only one external group, Aposturisoma myriodon Isbrücker, Britski, Nijssen & Ortega, 1983 (= Farlowella myriodon), that was used to root the tree; the monophyly of the genus, and species relationships were not actually tested. The authors also proposed six species groups and six species were considered as incertae sedis.
Recently, Londoño-Burbano, Reis (2021), based on combined molecular and morphological phylogenetic analysis, formally recognized Aposturisoma myriodon as a member of Farlowella to assign the monophyly of the genus. Although A. myriodon is phenotypically different from Farlowella, this configuration had already been recovered by Covain et al., (2016). Based on the review of Farlowella material deposited in different collections and on the examination of material collected in the river near the confluence with rio Tapajós, in its lower portion, we identified a new species of Farlowella, which is described herein.
MATERIAL AND METHODSMeasurements were taken point to point with digital calipers. Measurements are expressed as percents of the standard length (SL), except subunits of head, which are expressed as percents of the head length (HL). Measurements follow Boeseman, (1971), except measurement of distance from pectoral-fin origin to pelvic-fin origin that follow Retzer, Page (1996), plus minimum width of snout (minimum width at the tip of snout) (Fig. 1A), distance between cleithral processes (between the humeral processes of the cleithrum) (Fig. 1B) and maximum width of snout (maximum width in transverse line from the posterior edge of the ventral plate before mouth) (Fig. 1C). Counts and nomenclature of lateral plate series follow Ballen et al., (2016a). Osteological nomenclature follows Paixão, Toledo-Piza, (2009), except for parieto-supraoccipital instead of supraoccipital (Arratia, Gayet, 1995), pterotic-extraescapular instead of pterotic-supracleithrum (Slobodian, Pastana, 2018). Vertebral counts include only free centra, with the compound caudal centrum (preural 1+ ural 1) counted as a single element. Cleared and stained (cs) specimens were prepared according to the methods of Taylor, Van Dyke, (1985). Numbers in parentheses following meristic counts correspond to number of specimens having that count, and those indicated by an asterisk (*) belong to the holotype. Map was generated in the QGIS 3.14.16 program. Institutional abbreviations follow Sabaj, (2022). The estimated Extent of Occurrence (EOO) and Area of Occupation (AOO) of the species was calculated using the web portal of the Geospatial Conservation Assessment Tool (GeoCAT: http://geocat.kew.org/) and the categories and criteria of conservation status of species followed IUCN (IUCN Standards and Petitions Committee, 2022).
FIGURE 1 |
Additional measures used in this study. A. Minimum width of snout; B. Distance between cleithral processes; and C. Maximum width of snout.
RESULTSFarlowella wuyjugu, new species
urn:lsid:zoobank.org:act:FA22FB00-B26F-45C0-A121-2BD8FB00B523
(Figs. 2–3; Tab. 1)
Holotype. MPEG 26178, 143.4 mm SL, Brazil, Pará State, Juruti municipality, lower rio Tapajós, rio Amazon basin, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça.
Paratypes. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. INPA 59894, 2, 124.8–128.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MNRJ 53691, 2, 127.3–130.9 mm SL, same locality as INPA 59894. MPEG 10062, 5, 112.0–121.6 mm SL, same locality as INPA 59894, 3 Mar 2006, L. F. A. Montag. MPEG 12865, 5, 90.9–123.2 mm SL, same locality as INPA 59894, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 15900, 12, 2 cs, 97.6–136.5 mm SL, same locality as INPA 59894, 8 Sep 2002, W. B. Wosiacki. MPEG 10857, 5, 111.7–128.2 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Aug 2006, A. Hercos. MPEG 32191, 4, 94.3–133.9 mm SL, same locality as MPEG 10857, 14 Sep 2014, M. B. Mendonça. MPEG 12684, 5, 1 cs, 122.8–144.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°50’13.8”W, 14 Dec 2006, L. F. A. Montag.
Non-types. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. MPEG 10055, 4, 102.9–124.3 mm SL, MPEG 10062, 13, 70.0–109.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 3 Mar 2006, L. F. A. Montag. MPEG 10851, 1, 119.2 mm SL, MPEG 10852, 3, 79.5–116.1 mm SL, MPEG 10853, 1, 121.9 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10855, 4, 46.7–88.7 mm SL, MPEG 10856, 7, 54.2–108.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10857, 11, 65.1–145.8 mm SL, MPEG 10858, 2, 106.2–112.8 mm SL, MPEG 10859, 4, 64.4–128.3 mm SL, MPEG 10861, 1, 113.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10860, 1, 128.6 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10862, 3, 49.6–54.6 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10956, 1, 26.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 12491, 4, 18.6–45.8 mm SL, igarapé Mutum, 02°36’44.8”S 56°11’37.3”W, 9 Sep 2002, W. B. Wosiacki. MPEG 12865, 4, 69.8–93.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 13040, 2, 35.7–38.4 mm SL, MPEG 13043, 2, 20.6–30 mm SL, MPEG 13050, 2, 11.0–118.4 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, L. F. A. Montag. MPEG 13041, 1, 56.3 mm SL, MPEG 13044, 5, 56.8–93.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 12 Dec 2006, L. F. A. Montag. MPEG 13042, 3, 48.1–45.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13045, 1, 92.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13046, 1, 101.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 Dec 2006, L. F. A. Montag. MPEG 13048, 5, 50.2–80.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 Dec 2006, L. F. A. Montag. MPEG 13731, 2, 63.9–69.4 mm SL, MPEG 14143, 7, 61.9–136.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 May 2007, A. Hercos. MPEG 14271, 1, 42.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 27 Nov 2007, A. Hercos. MPEG 14711, 13, 46.2–126.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 May 2007, A. Hercos. MPEG 15900, 8, 56.6–95.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MPEG 16955, 1, 120.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’33.2”S 56°11’33.4”W, 19 Feb 2008, W. B. Wosiacki. MPEG 26172, 13, 71.8–129.8 mm SL, MPEG 26173, 4, 61.5–94.5 mm SL, MPEG 26333, 1, 86.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 28 Nov 2012, M. B. Mendonça. MPEG 26179,19, 43.5–156.4 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça. MPEG 29996, 2, 112.7–117.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 6 Dec 2013, M. B. Mendonça. MPEG 26997, 9, 100.5–129.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 7 Dec 2013, M. B. Mendonça. MPEG 26998, 1, 88.9 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 11 Dec 2013, M. B. Mendonça. MPEG 26999, 5, 51.9–138.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 12 Dec 2012, M. B. Mendonça. MPEG 32191, 4, 93.7–136.6 mm SL, MPEG 32192, 2, 55.6–115.1 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Sep 2014, M. B. Mendonça. MPEG 32193, 15, 32.9–124.2 mm SL, MPEG 32194, 14, 61.4–127.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 22 Sep 2014, M. B. Mendonça. MPEG 32195, 1, 135.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 18 Sep 2014, M. B. Mendonça. MPEG 32507, 72.4–113.1 mm S, MPEG 32508, 11, 49.0–116.5 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 20 Mar 2015, M. B. Mendonça.
FIGURE 2 |
Dorsal, lateral and ventral view of Farlowella wuyjugu, holotype, 143.4 mm SL, MPEG 26178, Brazil, Pará State, Juruti municipality, igarapé Rio Branco, lower rio Tapajós, rio Amazon basin.
Diagnosis.Farlowella wuyjugu can be diagnosed from its congeners by lack of plates in gular region (vs. gular plates present) (Fig. 3). The new species can be distinguished from its congeners, except Farlowella altocorpus Retzer, 2006, F. azpelicuetae Terán, Ballen, Alonso, Aguilera & Mirande, 2019, F. gianetii Ballen, Pastana & Peixoto, 2016, F. gracilis Regan, 1904, F. guarani Delgadillo, Maldonado & Carvajal-Vallejos, 2021, F. hasemani Eigenmann & Vance, 1917, F. isbrueckeri Retzer & Page, 1997, F. jauruensis Eigenmann & Vance, 1917, F. myriodon, F. nattereri Steindachner, 1910, and F. odontotumulusRetzer & Page, 1997, by having five lateral series of plate rows on anterior region of body (vs. four). Additionally, F. wuyjugu differs from F. altocorpus and F. azpelicuatae by having a smaller body width at dorsal origin (4.3–5.5 vs. 6.4–8.1% SL); from F. gianetti by number of caudal-fin rays (i,11,i or i,12,i vs. i,10,i); from F. gracilis by having head triangular in dorsal view (vs. head square); from F. guarani by interorbital width (12.0–16.0 vs. 28.6–44% HL) and eye diameter (3.6–5.8 vs. 6.6–13.3% HL); from F. hasemani by all fin rays uniformly pigmented (vs. fin rays not pigmented); from F. isbruckeri and F. odontotumulus by having the ventromedian row of anterior plates keeled (vs. ventromedian row of anterior plates unkeeled); from F. jauruensis by having five branched pelvic-fin rays (vs. four branched pelvic-fin rays); from F. myriodon by having dark brown lateral stripe on each side of snout (vs. absence of such stripe, snout completely dark); and from F. nattereri by having a short pectoral fin, not reaching the pelvic-fin base (vs. long pectoral fin, reaching the pelvic-fin base).
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TABLE 1 |
Morphometrics of Farlowella wuyjugu, new species. Values as percents of standard length (SL) and head length (HL) for holotype and 38 paratypes. n = number of specimens, SD = Standard deviation.
Description. Dorsal, lateral, and ventral views of holotype in Fig. 2. Morphometric and meristic data for holotype and paratypes summarized in Tab. 1. Body slender and very elongated, completely covered by dermal plates, except in gular portion. Head triangular and elongate in dorsal and ventral views. Rostrum slender and flat in ventral view. Orbit circular, dorsolaterally placed, visible in dorsal view and not visible in ventral view. Preorbital ridge present. Mouth ventral. Dorsal profile of head concave from snout tip to anterior margin of nares, relatively straight to convex from point to posterior margin of nares to posterior margin of parieto-supraoccipital and slightly concave to dorsal-fin origin. Posterior profile of margin of dorsal-fin origin slightly concave and straight profile to end of caudal peduncle. Ventral profile slightly straight from tip of snout to anal-fin origin, slightly concave in anal-fin base and straight profile to end of caudal peduncle.
Mouth ovoid, lower lip longer than upper lip; wide oval papillae on upper lip and round papillae on lower lip, decreasing in size from oral aperture to lip margin; lip margin papillose. Bicuspid slender teeth, each premaxilla with 22(2), 23*(1), 29(1), 31(1), 33(1), 36(1), 37(3), 39(1), 40(2), 41(1), 42(3), 43(2), 44(1), 46(3), 47(4), 48(4), 49(4), 51(2), 53(1) or 55(1) teeth and each dentary with 18*(3), 22(1), 23(1), 26(2), 28(1), 29(2), 30(2), 32(3), 33(3), 34(1), 35(4), 36(3), 37(1), 38(4), 39(2), 40(2), 41(1), 42(1) or 43(2) teeth; premaxilla larger than dentary. Two maxillary barbels small and projecting slightly from mouth margin.
Five lateral plate rows on body, with 31(6), 32*(30) or 33(3) dorsal plates; 6(1), 7*(5), 8(23) or 9(10) dorsomedian plates; 7(1), 8*(5), 9(20) or 10(13) median plates; 14*(7), 15(27) or 16(5) ventromedian plates; 35(3), 36(7), 37*(15), 38(9), 39(3) or 40(2) ventral plates; 5(14), 6*(18), 7(6) or 8(1) dorsomedian+median plates; 18(12), 19(20) or 20*(7) coalescent plates; 8*(39) predorsal plates; 23(6), 24*(30) or 25(3) postdorsal plates; 20(2), 21(14), 22*(21), 23(1) or 24(1) postanal plates; 2 plates at the base of caudal fin and one preanal plate. Abdomen covered with two lateral rows with 6(6), 7*(19), 8(11), 9(2), 11(1) lateral abdominal plates (left) and 6(10), 7*(14), 8(8) or 9(7) lateral abdominal plates (right), and one midabdominal incomplete (23)* row or when complete (16) row with 2(1), 3(2), 4*(2), 5(1), 6(5), 7(7), 8(7), 9(3), 10(3), 11(2), 12(3), 13(2) or 16(1) midabdominal plates.
Lateral line complete; reaching up to last caudal peduncle coalesced plate. Preopercular canal passing through infraorbital six with two pores. Terminal exit of parietal branch in frontal bone curved. Canal-bearing cheek plate in ventral position. Nasal slightly curved in anterior portion with pore opening laterally.
Pectoral-fin rays i,6*(39); posterior margin slightly concave; unbranched ray longest. Dorsal-fin rays i,6*(39); posterior margin straight to slightly concave; three* or four plates along its base; unbranched ray longest. Pelvic-fin rays i,5*(39); posterior margin straight; unbranched ray longest. Anal-fin rays i,5*(39); posterior margin straight to slightly concave; unbranched ray longest; three* or four plates along its base. Caudal-fin rays i,11,i(2) or i,12,i*(37); posterior margin deeply concave; dorsal and ventral lobes similar in size; filaments on upper and lower unbranched rays. All fin rays with odontodes; more developed odontodes on unbranched first ray.
Mesethmoid long; lateral expansion of anterior portion absent; mesethmoid ventral posterior process present. Nasal rectangular irregular bone curved laterally. Frontal wide, occluded from dorsal border of orbit. Orbit anteriorly delimited by dermal plate, dorsally by frontal bone, dorsolaterally by sphenotic, and ventrally by infraorbital series. Sphenotic quadrate in shape, contacting frontal bone anterolaterally, parieto-supraoccipital dorsally, infraorbital six ventrally, and pterotic-extrascapular posteriorly. Pterotic-extrascapular with large perforations. Parieto-supraoccipital wide and oval, contacting first predorsal plate posteriorly. Anterior contact of hyomandibula with metapterygoid and quadrate, and ventral with preopercle. Symphyseal cartilage between quadrate and hyomandibula. Anterior margin of quadrate articulation with anguloarticular. Dentary almost twice the size of anguloarticular. Autopalatine irregular, rod-like shape. Anterior margin of autopalatine articulation with maxilla and posterior contact posteriorly with vomer and metapterygoid. Preopercle long and partially exposed; anterior process reaching at least half of quadrate length. Suspensorium rectangular in overall shape. Three branchiostegal rays. Hypohyal anterior border straight, without anterior projection. Urohyal triangular and posterior margin rounded, with medial foramen. Anterohyal and posterohyal partially separated by cartilage. Anterior margin of anterohyal greatly expanded. Basibranchial 2, 3 and 4 present; basibranchial 2 and 3 elongated; basibranchial 2 equal to basibranchial 3; basibranchial 2 and 3 ossified and basibranchial 4 cartilaginous. Two hypobranchials; hypobranchial 1 ossified and hypobranchial 2 cartilaginous. Four epibranchials with similar size. Five ceratobranchials; ceratobranchial 1 with accessory flange; ceratobranchial 5 triangular; ceratobranchial teeth restricted to mesial area of plate. Upper pharyngeal plate club-shaped, completely covered with fine teeth. Vertebral count 39(1) and 40(1); five thin pleural ribs directly attached to centra 8, 9, 10, 11 and 12(1) and four thin pleural ribs directly attached to centra 9, 10, 11 and 12(1); parapophysis of complex vertebra well developed (two specimens).
FIGURE 3 |
Gular region and variation of abdominal plates in specimens, ventral view of Farlowella wuyjugu. A. MPEG 26178, 143.4 mm SL; B. INPA 59894, 128.9 mm SL; C. MPEG 12684, 125 mm SL.
Coloration in alcohol. Ground color of dorsum and head pale or dark brown. Light brown color with diffuse and scattered dark brown spots on predorsal portion, from tip of parieto-supraoccipital and extending to all plates. Five to six rounded spots between the second and third infraorbital, extending to opercle. One dark brown lateral stripe on each side, that runs from snout to caudal peduncle. Ventral portion of head brown; yellow between lower lip and anterior portion of anal fin. Dorsal profile in posterior portion of anal fin light brown with diffuse and scattered dark brown spots along the plates, same to dorsal portion, more delimited in some individuals. Upper lip with scattered chromatophores. Pectoral, dorsal, pelvic, and anal fin rays with hyaline membranes and pigmented brown rays, sometimes forming dark bands. First rays markedly dark. Caudal fin almost completely dark brown, membranes and rays pigmented, in some individuals with area of hyaline membrane (Fig. 4).
FIGURE 4 |
Caudal fin coloration of Farlowella wuyjugu. MPEG 31191, 119.9 mm SL.
Geographical distribution.Farlowella wuyjugu is known only from small, forest creeks near Juruti, Pará State, tributaries of rio Arapiuns, rio Tapajós in its lower portion, rio Amazon basin, Brazil (Fig. 5).
FIGURE 5 |
Geographic distribution of Farlowella wuyjugu in lower rio Tapajós. Star = holotype; circles = paratypes localities.
Etymology. The specific epithet refers to the combination of the words Wuy jugu, which is the self-denomination of indigenous people known in Brazil as Munduruku. This ethnic group is part of the Tupi trunk and they are located in different regions and territories in the states of Pará, Amazonas, and Mato Grosso. In the region of the lower Tapajós River, in recent years some communities in the process of their ethnic identity have recognized themselves as Munduruku (Ramos, 2022). A noun in apposittion.
Conservation status.Farlowella wuyjugu is known from four collection stations [igarapé Rio Branco (Fig. 6), igarapé Mutum, and igarapé São Francisco] in Juruti municipality, Pará State, Brazil. Using the GeoCAT we calculate the extent of occurrence (EOO) of the species in 4,921 km2, suggesting a threatened category of Endangered (EN). Farlowella wuyjugu is sampled in few localities in the Juruti municipality, impacted by a large bauxite extraction project, deteriorating their habitats. Following the recommendations by the IUCN (IUCN Standards and Petitions Committee, 2022), F. wuyjugu should be categorized as Nearly Threatened (NT), following criterions B2:EN (EOO < 5,000 km2), b(iii) (decline of quality of habitat by bauxite extraction).
FIGURE 6 |
Igarapé Rio Branco, type-locality of Farlowella wuyjugu.
Variation of abdominal plates within Farlowellawuyjugu. Abdominal plates are usually termed as lateral abdominal plates, which are transversely elongated plates between the pectoral-fin axilla and the pelvic-fin insertion, and midabdominal plates, which cover the abdomen between the lateral ones (Londoño-Burbano, Reis, 2021). The midabdominal plates, in Farlowella, can be absent or present and when present can be incomplete or complete. Ballen et al., (2016b) described Falowella mitoupiboBallen, Urbano-Bonilla & Zamudio, 2016 and proposed as diagnostic for the species an incomplete median disjunct row of abdominal plates, divided at the center by plates belonging to the lateral rows of abdominal plates (vs. two or three complete rows of abdominal plates or an incomplete median row of one or two plates anteriorly that never reach to the level of the prepelvic plate). Although the authors proposed this character as a diagnosis for the species, in recent examinations of the type material of F. mitoupibo, it was possible to observe two completes rows of abdominal plates in one specimen (M. Dopazo, pers. obs.). Farlowella wuyjugu have midabdominal plates and can be an incomplete or complete midabdominal series (Fig. 3). An incomplete midabdominal series can be a disjunct row as described for F. mitoupibo or an incomplete median row of plates anteriorly that do not reach to the level of the prepelvic plate (Figs. 3A, B). Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species group of Farlowella: two rows (F. acus (Kner, 1853) group and F. amazonumGünther, 1864 group) and three rows (F. curtirostra Myers, 1942 group, F. mariaelene Martín Salazar, 1964 group, F. nattereri group, F. knerii (Steindachner, 1882) group and unassigned species group). Although Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species groups of Farlowella, both states were found in F. wuyjugu and F. mitoupibo, rendering that character not be useful to differentiate groups because they are variable within Farlowella species. A phylogenetic analysis of the genus (including the species described here) is being carried out and aims to test if these characters (proposed by Retzer, Page, 1996) are in fact phylogenetically informative.
DISCUSSIONLondoño-Burbano, Reis (2021) recovered the tribe Farlowellini Fowler, 1958 including five genera, Lamontichthys Miranda Ribeiro, 1939, Pterosturisoma Isbrücker & Nijssen, 1978, Sturisoma Swainson, 1838, Sturisomatichthys Isbrücker & Nijssen, 1979 and Farlowella Eigenmann & Eigenmann, 1889. The authors defined two exclusive synapomorphies for the tribe: (1) nuchal plate articulated to lateral plates (char 175) and (2) the presence of gular plates (char 179). According to Londoño-Burbano, Reis (2021), gular plates are large, polygonal dermal plates covering the ventral surface of the head behind the lower lip. Character 175 was observed in F. wuyjugu, however, character 179 is not applicable to the new species because of the lack of gular plates. Almost twenty years after the publication of the study by Retzer, Page (1996). Farlowella was proposed as a monophyletic group by Londoño-Burbano, Reis (2021) with 11 morphological and 38 molecular synapomorphies. Of the eleven morphological synapomorphies, four were considered exclusive for the genus: (1) number of branchiostegal rays fewer than four (char 109); (2) straight and upright lamina on neural spine on the sixth vertebra for articulation with ventral surface of parieto-supraoccipital (char 114); (3) absence of pleural rib associated to the seventh vertebra (char 117); (4) short anteriormost paraneural spines (char 129). These character states were all observed in F. wuyjugu supporting the species as a member of the genus. Despite the high number of morphological characters and the number of terminals used in the analysis by the authors, there are many high homoplastic characters and not useful for a diagnosis at the species level.
Other Farlowella species are also identified for the rio Tapajós basin (F. gr. amazonum, F. cf. oxyrryncha, F. schreitmuelleri Arnold, 1936, and F. sp.; M. Dopazo, pers. obs.). Species with type locality in or near the region are F. amazonum (Santarém, Pará State), F. gladiolusGünther, 1864 (rio Cupari, rio Tapajós basin, Amazon River drainage, Pará State), and F. schreitmuelleri (lower Amazon River basin, Santarém, Pará State), but they differ from F. wuyjugu mainly by the number of lateral series of plate rows on anterior region of body (four vs. five). Farlowella amazonum and F. gladiolus were described in the same work by Günther, (1864). In the review of the genus by Retzer, Page (1996), F. gladiolus was placed in the synonymy with F. amazonum, however, Covain et al., (2016) recognized the former as a valid species. There are several taxonomic issues regarding the validity of Farlowella species and their delimitation. These questions are being addressed in an ongoing taxonomic review (by MD and MRB) of the genus. Our description of F. wuyjugu contributes to the knowledge of the rio Arapiuns and to the understanding of the ichthyofauna of the rio Tapajós basin.
Comparative material examined.Farlowella acus: Colombia: MPUJ 2834, 1, 183.6 mm SL; MPUJ 2842, 1, 133.3 mm SL; MPUJ 2955, 1, 50.1 mm SL: MPUJ 7320,1 124.1 mm SL; MPUJ 9287, 1, 122.5 mm SL; MPUJ 10915, 1, 116.9 mm SL; MPUJ 11158, 1, 130.4 mm SL; MPUJ 13270, 1, 38.6 mm SL: MPUJ 16876, 1, 76 mm SL; Venezuela: ANSP 130038, 20, 90.6–149.7 mm SL; MZUSP 147, 2, 108.4–123.8 mm SL; Farlowella cf. altocorpus: Brazil: INPA 3034, 49, 64.2–155.6 mm SL; INPA 3035, 16, 58–148.6 mm SL; Farlowella amazonum: Brazil: LIA 7233, 1, 84.7 mm SL; LIA 7235, 64.8–198.5 mm SL; LIA 7236, 4, 69.2–92,5 mm SL; LBP 4344, 1, 82.9 mm SL; LBP 10860, 3, 111.0–144.7 mm SL; LBP 11118, 1, 132.2 mm SL; LBP 12117, 5, 47.4–147.2 mm SL; LBP 15179, 1, 82.9 mm SL; LBP 17994, 3, 70.7–121.81 mm SL; LBP 20432, 1, 110.1 mm SL; LBP 20964, 2, 67.5–113.1 mm SL; LBP 21208, 4, 69.5–121.7 mm SL; LBP 21230, 1, 142.1 mm SL; LBP 22348, 13, 54.9–203.6 mm SL; LBP 22488, 1, 169.2 mm SL; MCP 44240, 6, 163.8–190.7 mm SL; MCP 50059, 83.6–176.4 mm SL; MNRJ 762, 3, 130.1–161.2 mm SL; MNRJ 35534, 15, 79.9–166.1 mm SL, 3 cs; MNRJ 35535, 3, 176.3–161.3 mm SL; MNRJ 35536, 2, 76.3–176.8 mm SL; MNRJ 35537, 2, 99.7–179.9 mm SL; MNRJ 39040, 8, 52.1–73.7 mm SL; MNRJ 39249, 1, 66.6 mm SL; MNRJ 39270, 6, 34.4–66.8 mm SL; MPEG 3072, 2, 71,7–146.2 mm SL; MPEG 9008, 4, 147–182.3 mm SL; MPEG 13290, 5, 157.9–180.3 mm SL; MPEG 17077, 1, 50.8 mm SL; MPEG 19827, 1, 182.2 mm SL; MPEG 19945, 1, 123.8 mm SL; MPEG 23942, 2, 139–175.4 mm SL; MPEG 23726, 2, 166.4–172.5 mm SL; MPEG 24470, 1, 129.2 mm SL; MPEG 24471, 2, 166.3–74 mm SL; MPEG 30598, 5, 118.3–151.1 mm SL; MPEG 30931, 1, 104.2 mm SL; MPEG 30936, 1, 109.7 mm SL; MZUSP 23416, 5, 35.9–139.2 mm SL; MZUSP 27717, 1, 115.8 mm SL; MZUSP 121244, 1, 207.0 mm SL; UFRGS 21710, 1, 80.5 mm SL; Peru: ANSP 191818, 2, 172.7–179.6 mm SL; ANSP 199910, 1, 146.1 mm SL; Farlowella azpelicuetae: Argentina: MZUSP 123935, paratype, 80.8 mm SL; MZUSP 123936, 2, paratypes, 79.8–165.9 mm SL; Farlowella gianetti: Brazil: MZUSP 95564, holotype, 114.4 mm SL; MZUSP 97022, paratypes, 94.1–118.6 mm SL; Farlowella cf. hahni: Brazil: MZUEL 9037, 5, 56.6–131 mm SL; MZUEL 9669, 1, 47.2 mm SL; NUP 374, 6, 78.1–161.7 mm SL; NUP 818, 5, 127.6–140 mm SL; NUP 819, 10, 89.3–156.2 mm SL; NUP 1450, 1, 111.7 mm SL; NUP 1496, 5, 95.7–177.8 mm SL; NUP 2849, 1, 128.4 mm SL; NUP 4029, 2, 151.1–162.2 mm SL; NUP 4525, 1, 130.7 mm SL; NUP 4728, 5, 129.4–148 mm SL; NUP 7867, 2, 134.7–140.3 mm SL; NUP 11443, 1, 109.5 mm SL; NUP 13303, 2, 103.2–129.7 mm SL; NUP 14747, 1, 125.6 mm SL; NUP 16978, 2, 133.8–149.8 mm SL; Farlowella hasemani: Brazil: INPA 3912, 190.8 mm SL; Farlowella henriquei: Brazil: INPA 3012, 2, 68.8–111 mm SL; INPA 3030, 1, 170.3 mm SL; INPA 3911, 147.9–153.1 mm SL; INPA 3913, 1, 180.7; INPA 34545, 3, 83.6–160.5 mm SL; MZUSP 2159, holotype, 165.7 mm SL; Farlowella isbruckeri: Brazil: MZUSP 27704, paratype, 134.8 mm SL; Farlowella jauruensis: Brazil: MZUSP 59457, 2, 58.3–57.3 mm SL; MZUSP 58485, 1, 77.2 mm SL; MZUSP 115560, 1, 81.4 mm SL; Farlowella knerii: Ecuador: ANSP 130435, 2, 21.4–73.3 mm SL; ANSP 130436, 1, 123.3 mm SL; Farlowella latisoma: Brazil: MNRJ 761, holotype, 179.3 mm SL, synonymy of Farlowella schreitmuelleri; Farlowella mariaelenae: Venezuela: ROM 94123, 2, 67.2–81.8 mm SL; Farlowella mitoupibo: Colombia: MPUJ 8481, holotype, 203.7 mm SL; MPUJ 8479, 1, paratype, 112.6 mm SL; MPUJ 8480, paratype, 5, 65.7–170 mm SL; MPUJ 8482, paratype, 109.4 mm SL; MPUJ 8483, paratype, 1, 163.1 mm SL; MPUJ 8484, paratype, 1, 112.5 mm SL; Farlowella myriodon: Peru: MZUSP 15328, holotype, 154 mm SL; MZUSP 15332, paratype, 134.2 mm SL; MZUSP 15342, paratype, 92.6 mm SL; Farlowella nattereri: Brazil: LBP 10568, 3, 80.7–92.4 mm SL; LBP 18192, 6, 47.5–117.5 mm SL; LBP 18526, 1, 189.9 mm SL; LBP 18580, 3, 102.9–164.5 mm SL; LBP 26628, 7, 185.0–208.6 mm SL; MNRJ 3732, 2, 166.9–168.2 mm SL; MNRJ 37080, 1, 135.7 mm SL; UFRO–ICT 6731, 2, 96.4–104.6 mm SL; UFRGS 26186, 1, 147.7 mm SL; Colombia: ROM 107219, 3, 90.3–213 mm SL; Peru: LBP 22594, 1, 132.3 mm SL; ROM 64063, 6, 42.9–129.8 mm SL; Farlowella aff. nattereri: Brazil: INPA 1637, 1, 117.8 mm SL; INPA 1963, 2, 78.7–146.1 mm SL; INPA 2017, 1, 87.5 mm SL; INPA 2808, 1, 171.8 mm SL; INPA 3916, 1, 95 mm SL; INPA 4839, 1, 184.5 mm SL; INPA 12945, 1, 162.5 mm SL; INPA 16763, 1, 52 mm SL; INPA 43891, 1, 199.1 mm SL; Guyana: INPA 58225, 2, 135.6–52.7 mm SL; ROM 97162, 1, 112.3 mm SL; Farlowella oliveirae Miranda Ribeiro, 1939: MNRJ 757, holotype, 111.8 mm SL, synonymy of Farlowella amazonum; Farlowella aff. oxyrryncha: Brazil: INPA 12940, 6, 61–155.2 mm SL; INPA 12941, 1, 60.5 mm SL; INPA 29869, 5, 29.9–105.1 mm SL; INPA 31038, 1, 100.3 mm SL; MZUEL 6713, 1, 103 mm SL; Farlowella cf. oxyrryncha: Brazil: INPA 1645,1, 86.4 mm SL; INPA 8159, 3, 61.9–151.6 mm SL; INPA 10371, 21, 72.33–188 mm SL; INPA 12964, 1, 56.3 mm SL; INPA 14001, 1, 159.2; INPA 20796, 1, 134.4 mm SL; INPA 27505, 21, 23.9–129.3 mm SL; INPA 37694, 1, 75 mm SL; INPA 53229, 1, 199.8 mm SL; INPA 54977, 1, 110 mm SL; INPA 58662, 1, 170.5 mm SL; MCP 32735, 1, 83 mm SL; MCP 36623, 7, 51.6–112.7 mm SL; MCP 46138, 1, 103 mm SL; MPEG 13083, 3, 116.4–127 mm SL; MPEG 28662, 5, 73.7–178.5 mm SL; MPEG 30901, 1, 103.7 mm SL; UFRGS 12165, 4, 105,5–97.7 mm SL; UFRGS 12325, 5, 49.8–133.6 mm SL; UFRGS 21842, 1, 100.3 mm SL; MNRJ 23380, 1, 115.4 mm SL; MZUSP 22919, 6, 47.7–101.8 mm SL; MZUSP 96753, 8, 55.9–101 mm SL; MZUSP 125342, 10, 69.2–195 mm SL; Farlowella paraguayensis Retzer & Page, 1997: Brazil: INPA 567, 5, 72.3–122.1 mm SL; INPA 2829, 4, 65.1–135 mm SL; INPA 2830, 6, 70.5–153.2; INPA 3919, 12, 56.5–88.7 mm SL; INPA 12999, 4, 59.8–110.7 mm SL; MNRJ 760, 1, 162.0 mm SL; MNRJ 46680, 2, 117.8–118.3 mm SL; MZUSP 47243, 8, paratypes, 122.5–134.4 mm SL; NUP 15010, 8, 51.7–95.8 mm SL; NUP 21531, 5, 56.3–101 mm SL; ZUFMS 1292, 2, 134.6–143.3 mm SL; ZUFMS 1426, 3, 112.9–122.3 mm SL; ZUFMS 4373, 3, 113.7–128.4 mm SL; ZUFMS 5950, 4, 74.2–122.9 mm SL; Farlowella pleurotaenia Miranda Ribeiro, 1939: Brazil: MNRJ 758, holotype, 99.6 mm SL, synonymy of Farlowella amazonum; Farlowella rugosa Boeseman, 1971: Brazil: IEPA 3886, 1, 187.2 mm SL; IEPA 3916, 1, 113.6 mm SL; Guyana: ROM 64797, 1, 143.5 mm SL; ROM 85790, 3, 73.9–87.4 mm SL; ROM 85916, 1, 73.7 mm SL; ROM 85922, 2, 81.9–143.1 mm SL; ROM 86116, 2, 63.5–65 mm SL; Suriname: ROM 98122, 1, 90.64 mm SL; Farlowella schreitmuelleri: Brazil: IEPA 2708, 1, 59 mm SL; IEPA 4644, 1, 66.9 mm SL; IEPA 4708, 1, 63.1 mm SL, IEPA 4724, 2, 80.1–121.8 mm SL; IEPA 4727, 6, 63.3–120.6 mm SL; INPA 3917, 1, 82.8 mm SL; INPA 3918, 1, 76.2 mm SL; INPA 6777, 9, 63.1–104.7 mm SL; INPA 6978, 3, 67.6–111.3 mm SL; INPA 7069, 1, 76 mm SL; INPA 8209, 1, 75.8 mm SL; INPA 24914, 11, 78.8–125.4 mm SL; INPA 29109, 2, 55.3–66.5 mm SL; INPA 44877, 5, 66.2–111 mm SL; INPA 44493, 1, 110.1 mm SL; INPA 44662, 1, 71.4 mm SL; INPA 45127, 2, 99.4–113.3 mm SL; INPA 45891, 13, 59.5–115.4 mm SL; INPA 46005, 1, 98.6 mm SL; INPA 46027, 1, 119.7 mm SL; MZUSP 101583, 2, 91.6–132 mm SL; MZUSP 101828, 1, 93.1 mm SL; UNT 488, 3, 106.5–140.7 mm SL; UNT 488, 3, 106.5–140.7 mm SL; Farlowella smithi Fowler, 1913: Brazil: UFRGS 25175, 3, 60.9–71.8 mm SL; UFRO–ICT 507, 3, 64.8–89.9 mm SL; UFRO–ICT 24122, 3, 70.3–88.9 mm SL; MZUSP 73593, 14, 56.9–85.8 mm SL; Farlowella vittata Myers, 1942: Colombia: LBP 18722, 2, 51.9–130.6 mm SL; MPUJ 8349, 8, 37.4–124.4 mm SL; MPUJ 8353, 2, 54.3–75.1 mm SL; MPUJ 8357, 7, 78.9–128.3 mm SL; Venezuela: LBP 2307, 1, 87.4 mm SL; LBP 9950, 2, 51.6–123.4 mm SL; ROM 88294, 6, 90.4–77.5 mm SL; ROM 94407, 3, 62–136.3 mm SL.
ACKNOWLEDGEMENTSWe are grateful to Mariangeles Arce and Mark Sabaj (ANSP); Cecile Gama (IEPA); Lucia Rapp Py-Daniel, Renildo Oliveira and Vitoria Pereira (INPA); Claudio Oliveira (LBP); Isaac Cabral and Leandro Sousa (LIA); Carlos Lucena (MCP); Alberto Akama and Angelo Dourado (MPEG); Alejandra Rodríguez, Tiago Carvalho and Saul Prada (MPUJ); Alessio Datovo, Guilherme Dutra, Mario de Pinna and Michel Gianeti (MZUSP); Carla Pavanelli and Marli Campos (NUPELIA); Marg Zur and Nathan Lujan (ROM); Fernando Jerep and José Birindelli (UEL); Juliana Wingert and Luiz Malabarba (UFRGS); Aline Andriolo and Carolina Doria (UFRO); Carine Chamon, Everton Oliveira and Paulo Lucinda (UNT); Francisco Severo Neto and Thomaz Sinani (ZUFMS) for loan material and assistance during visits of the first author to collections under their care. Alejandro Londoño-Burbano (MNRJ) for comments and discussion about the Loricariinae and generous contributions to this manuscript. Roberto Reis (MCP), Jonathan Armbruster (AUM) and an anonymous reviewer provided useful comments that helped improve the manuscript. Lucas Garcia (MNRJ) for the drawing of Fig. 1. Igor Souto-Santos (MNRJ) for helping with photos for Figs. 2, 3 and 4. Guilherme Dutra (MZUSP) for the photograph of the type locality. MD is supported from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES/PROEX 88887.335793/2019–00). MRB and WBW are supported by grants from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, processes #311294/2021–9 and #307988/2021–0).
Manuela DopazoWolmar B. WosiackiMarcelo R. BrittoABOUT THE AUTHORS
Keywords:
Amazon; Armored catfish; Biodiversity; Loricariinae; Taxonomy
ResumoUma nova espécie de cascudo-graveto Farlowella é descrita de pequenos igarapés do baixo rio Tapajós, no Estado do Pará, norte do Brasil. A nova espécie é distinta de todas as suas congêneres por uma região gular nua (vs. região gular com placas) e de muitas congêneres pela presença de cinco fileiras de placas laterais na região anterior do corpo (vs. quatro). A nova espécie apresenta variação na série de placas abdominais e é feita uma discussão sobre a variação das placas abdominais dentro de Farlowella e comentários sobre caracteres sinapomórficos em Farlowellini.
Palavras-chave:
Amazônia; Biodiversidade; Cascudo; Loricariinae; Taxonomia
INTRODUCTIONThe genus FarlowellaEigenmann & Eigenmann, 1889 is a component of the freshwater fish fauna of the Neotropics. With 32 valid species, Farlowella is the second-most species-rich genus of Loricariinae, a sub-family comprised of 262 valid species in 31 genera (Delgadillo et al., 2021; Londoño-Burbano, Reis, 2021; Fricke et al., 2023). Farlowella representatives are widely distributed in the main cis-Andean South America river drainages and trans-Andean Maracaibo and Magdalena river basins (Terán et al., 2019). They are easily distinguished by having a pronounced rostrum, a thin, elongated, brown body with two longitudinal bands that extend from the tip of the rostrum to the caudal peduncle (Covain, Fisch-Muller, 2007), resembling dry twigs or sticks, which justifies the popular name stick catfishes.
The first taxonomic study was the description of the genus Acestra by Kner, (1853), with the first species described: Acestra acus and A. oxyrryncha, but without designating the type species of the genus, until A. acus was determined by Bleeker, (1862). However, Acestra was already occupied in Hemiptera (Dallas, 1852) and the name Farlowella was then replaced by Eigenmann, Eigenmann, (1889). From the end of the 19th century, several species were described, totaling 37 names that remained for almost a century, when Retzer, Page (1996) revised the genus based on characters of external morphology. This was the last revision of its species, as well as the first exclusive hypothesis of the phylogenetic relationships of the genus. In that study, the authors performed a phylogenetic analysis with morphological data including only one external group, Aposturisoma myriodon Isbrücker, Britski, Nijssen & Ortega, 1983 (= Farlowella myriodon), that was used to root the tree; the monophyly of the genus, and species relationships were not actually tested. The authors also proposed six species groups and six species were considered as incertae sedis.
Recently, Londoño-Burbano, Reis (2021), based on combined molecular and morphological phylogenetic analysis, formally recognized Aposturisoma myriodon as a member of Farlowella to assign the monophyly of the genus. Although A. myriodon is phenotypically different from Farlowella, this configuration had already been recovered by Covain et al., (2016). Based on the review of Farlowella material deposited in different collections and on the examination of material collected in the river near the confluence with rio Tapajós, in its lower portion, we identified a new species of Farlowella, which is described herein.
MATERIAL AND METHODSMeasurements were taken point to point with digital calipers. Measurements are expressed as percents of the standard length (SL), except subunits of head, which are expressed as percents of the head length (HL). Measurements follow Boeseman, (1971), except measurement of distance from pectoral-fin origin to pelvic-fin origin that follow Retzer, Page (1996), plus minimum width of snout (minimum width at the tip of snout) (Fig. 1A), distance between cleithral processes (between the humeral processes of the cleithrum) (Fig. 1B) and maximum width of snout (maximum width in transverse line from the posterior edge of the ventral plate before mouth) (Fig. 1C). Counts and nomenclature of lateral plate series follow Ballen et al., (2016a). Osteological nomenclature follows Paixão, Toledo-Piza, (2009), except for parieto-supraoccipital instead of supraoccipital (Arratia, Gayet, 1995), pterotic-extraescapular instead of pterotic-supracleithrum (Slobodian, Pastana, 2018). Vertebral counts include only free centra, with the compound caudal centrum (preural 1+ ural 1) counted as a single element. Cleared and stained (cs) specimens were prepared according to the methods of Taylor, Van Dyke, (1985). Numbers in parentheses following meristic counts correspond to number of specimens having that count, and those indicated by an asterisk (*) belong to the holotype. Map was generated in the QGIS 3.14.16 program. Institutional abbreviations follow Sabaj, (2022). The estimated Extent of Occurrence (EOO) and Area of Occupation (AOO) of the species was calculated using the web portal of the Geospatial Conservation Assessment Tool (GeoCAT: http://geocat.kew.org/) and the categories and criteria of conservation status of species followed IUCN (IUCN Standards and Petitions Committee, 2022).
FIGURE 1 |
Additional measures used in this study. A. Minimum width of snout; B. Distance between cleithral processes; and C. Maximum width of snout.
RESULTSFarlowella wuyjugu, new species
urn:lsid:zoobank.org:act:FA22FB00-B26F-45C0-A121-2BD8FB00B523
(Figs. 2–3; Tab. 1)
Holotype. MPEG 26178, 143.4 mm SL, Brazil, Pará State, Juruti municipality, lower rio Tapajós, rio Amazon basin, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça.
Paratypes. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. INPA 59894, 2, 124.8–128.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MNRJ 53691, 2, 127.3–130.9 mm SL, same locality as INPA 59894. MPEG 10062, 5, 112.0–121.6 mm SL, same locality as INPA 59894, 3 Mar 2006, L. F. A. Montag. MPEG 12865, 5, 90.9–123.2 mm SL, same locality as INPA 59894, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 15900, 12, 2 cs, 97.6–136.5 mm SL, same locality as INPA 59894, 8 Sep 2002, W. B. Wosiacki. MPEG 10857, 5, 111.7–128.2 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Aug 2006, A. Hercos. MPEG 32191, 4, 94.3–133.9 mm SL, same locality as MPEG 10857, 14 Sep 2014, M. B. Mendonça. MPEG 12684, 5, 1 cs, 122.8–144.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°50’13.8”W, 14 Dec 2006, L. F. A. Montag.
Non-types. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. MPEG 10055, 4, 102.9–124.3 mm SL, MPEG 10062, 13, 70.0–109.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 3 Mar 2006, L. F. A. Montag. MPEG 10851, 1, 119.2 mm SL, MPEG 10852, 3, 79.5–116.1 mm SL, MPEG 10853, 1, 121.9 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10855, 4, 46.7–88.7 mm SL, MPEG 10856, 7, 54.2–108.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10857, 11, 65.1–145.8 mm SL, MPEG 10858, 2, 106.2–112.8 mm SL, MPEG 10859, 4, 64.4–128.3 mm SL, MPEG 10861, 1, 113.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10860, 1, 128.6 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10862, 3, 49.6–54.6 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10956, 1, 26.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 12491, 4, 18.6–45.8 mm SL, igarapé Mutum, 02°36’44.8”S 56°11’37.3”W, 9 Sep 2002, W. B. Wosiacki. MPEG 12865, 4, 69.8–93.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 13040, 2, 35.7–38.4 mm SL, MPEG 13043, 2, 20.6–30 mm SL, MPEG 13050, 2, 11.0–118.4 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, L. F. A. Montag. MPEG 13041, 1, 56.3 mm SL, MPEG 13044, 5, 56.8–93.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 12 Dec 2006, L. F. A. Montag. MPEG 13042, 3, 48.1–45.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13045, 1, 92.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13046, 1, 101.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 Dec 2006, L. F. A. Montag. MPEG 13048, 5, 50.2–80.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 Dec 2006, L. F. A. Montag. MPEG 13731, 2, 63.9–69.4 mm SL, MPEG 14143, 7, 61.9–136.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 May 2007, A. Hercos. MPEG 14271, 1, 42.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 27 Nov 2007, A. Hercos. MPEG 14711, 13, 46.2–126.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 May 2007, A. Hercos. MPEG 15900, 8, 56.6–95.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MPEG 16955, 1, 120.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’33.2”S 56°11’33.4”W, 19 Feb 2008, W. B. Wosiacki. MPEG 26172, 13, 71.8–129.8 mm SL, MPEG 26173, 4, 61.5–94.5 mm SL, MPEG 26333, 1, 86.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 28 Nov 2012, M. B. Mendonça. MPEG 26179,19, 43.5–156.4 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça. MPEG 29996, 2, 112.7–117.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 6 Dec 2013, M. B. Mendonça. MPEG 26997, 9, 100.5–129.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 7 Dec 2013, M. B. Mendonça. MPEG 26998, 1, 88.9 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 11 Dec 2013, M. B. Mendonça. MPEG 26999, 5, 51.9–138.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 12 Dec 2012, M. B. Mendonça. MPEG 32191, 4, 93.7–136.6 mm SL, MPEG 32192, 2, 55.6–115.1 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Sep 2014, M. B. Mendonça. MPEG 32193, 15, 32.9–124.2 mm SL, MPEG 32194, 14, 61.4–127.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 22 Sep 2014, M. B. Mendonça. MPEG 32195, 1, 135.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 18 Sep 2014, M. B. Mendonça. MPEG 32507, 72.4–113.1 mm S, MPEG 32508, 11, 49.0–116.5 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 20 Mar 2015, M. B. Mendonça.
FIGURE 2 |
Dorsal, lateral and ventral view of Farlowella wuyjugu, holotype, 143.4 mm SL, MPEG 26178, Brazil, Pará State, Juruti municipality, igarapé Rio Branco, lower rio Tapajós, rio Amazon basin.
Diagnosis.Farlowella wuyjugu can be diagnosed from its congeners by lack of plates in gular region (vs. gular plates present) (Fig. 3). The new species can be distinguished from its congeners, except Farlowella altocorpus Retzer, 2006, F. azpelicuetae Terán, Ballen, Alonso, Aguilera & Mirande, 2019, F. gianetii Ballen, Pastana & Peixoto, 2016, F. gracilis Regan, 1904, F. guarani Delgadillo, Maldonado & Carvajal-Vallejos, 2021, F. hasemani Eigenmann & Vance, 1917, F. isbrueckeri Retzer & Page, 1997, F. jauruensis Eigenmann & Vance, 1917, F. myriodon, F. nattereri Steindachner, 1910, and F. odontotumulusRetzer & Page, 1997, by having five lateral series of plate rows on anterior region of body (vs. four). Additionally, F. wuyjugu differs from F. altocorpus and F. azpelicuatae by having a smaller body width at dorsal origin (4.3–5.5 vs. 6.4–8.1% SL); from F. gianetti by number of caudal-fin rays (i,11,i or i,12,i vs. i,10,i); from F. gracilis by having head triangular in dorsal view (vs. head square); from F. guarani by interorbital width (12.0–16.0 vs. 28.6–44% HL) and eye diameter (3.6–5.8 vs. 6.6–13.3% HL); from F. hasemani by all fin rays uniformly pigmented (vs. fin rays not pigmented); from F. isbruckeri and F. odontotumulus by having the ventromedian row of anterior plates keeled (vs. ventromedian row of anterior plates unkeeled); from F. jauruensis by having five branched pelvic-fin rays (vs. four branched pelvic-fin rays); from F. myriodon by having dark brown lateral stripe on each side of snout (vs. absence of such stripe, snout completely dark); and from F. nattereri by having a short pectoral fin, not reaching the pelvic-fin base (vs. long pectoral fin, reaching the pelvic-fin base).
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TABLE 1 |
Morphometrics of Farlowella wuyjugu, new species. Values as percents of standard length (SL) and head length (HL) for holotype and 38 paratypes. n = number of specimens, SD = Standard deviation.
Description. Dorsal, lateral, and ventral views of holotype in Fig. 2. Morphometric and meristic data for holotype and paratypes summarized in Tab. 1. Body slender and very elongated, completely covered by dermal plates, except in gular portion. Head triangular and elongate in dorsal and ventral views. Rostrum slender and flat in ventral view. Orbit circular, dorsolaterally placed, visible in dorsal view and not visible in ventral view. Preorbital ridge present. Mouth ventral. Dorsal profile of head concave from snout tip to anterior margin of nares, relatively straight to convex from point to posterior margin of nares to posterior margin of parieto-supraoccipital and slightly concave to dorsal-fin origin. Posterior profile of margin of dorsal-fin origin slightly concave and straight profile to end of caudal peduncle. Ventral profile slightly straight from tip of snout to anal-fin origin, slightly concave in anal-fin base and straight profile to end of caudal peduncle.
Mouth ovoid, lower lip longer than upper lip; wide oval papillae on upper lip and round papillae on lower lip, decreasing in size from oral aperture to lip margin; lip margin papillose. Bicuspid slender teeth, each premaxilla with 22(2), 23*(1), 29(1), 31(1), 33(1), 36(1), 37(3), 39(1), 40(2), 41(1), 42(3), 43(2), 44(1), 46(3), 47(4), 48(4), 49(4), 51(2), 53(1) or 55(1) teeth and each dentary with 18*(3), 22(1), 23(1), 26(2), 28(1), 29(2), 30(2), 32(3), 33(3), 34(1), 35(4), 36(3), 37(1), 38(4), 39(2), 40(2), 41(1), 42(1) or 43(2) teeth; premaxilla larger than dentary. Two maxillary barbels small and projecting slightly from mouth margin.
Five lateral plate rows on body, with 31(6), 32*(30) or 33(3) dorsal plates; 6(1), 7*(5), 8(23) or 9(10) dorsomedian plates; 7(1), 8*(5), 9(20) or 10(13) median plates; 14*(7), 15(27) or 16(5) ventromedian plates; 35(3), 36(7), 37*(15), 38(9), 39(3) or 40(2) ventral plates; 5(14), 6*(18), 7(6) or 8(1) dorsomedian+median plates; 18(12), 19(20) or 20*(7) coalescent plates; 8*(39) predorsal plates; 23(6), 24*(30) or 25(3) postdorsal plates; 20(2), 21(14), 22*(21), 23(1) or 24(1) postanal plates; 2 plates at the base of caudal fin and one preanal plate. Abdomen covered with two lateral rows with 6(6), 7*(19), 8(11), 9(2), 11(1) lateral abdominal plates (left) and 6(10), 7*(14), 8(8) or 9(7) lateral abdominal plates (right), and one midabdominal incomplete (23)* row or when complete (16) row with 2(1), 3(2), 4*(2), 5(1), 6(5), 7(7), 8(7), 9(3), 10(3), 11(2), 12(3), 13(2) or 16(1) midabdominal plates.
Lateral line complete; reaching up to last caudal peduncle coalesced plate. Preopercular canal passing through infraorbital six with two pores. Terminal exit of parietal branch in frontal bone curved. Canal-bearing cheek plate in ventral position. Nasal slightly curved in anterior portion with pore opening laterally.
Pectoral-fin rays i,6*(39); posterior margin slightly concave; unbranched ray longest. Dorsal-fin rays i,6*(39); posterior margin straight to slightly concave; three* or four plates along its base; unbranched ray longest. Pelvic-fin rays i,5*(39); posterior margin straight; unbranched ray longest. Anal-fin rays i,5*(39); posterior margin straight to slightly concave; unbranched ray longest; three* or four plates along its base. Caudal-fin rays i,11,i(2) or i,12,i*(37); posterior margin deeply concave; dorsal and ventral lobes similar in size; filaments on upper and lower unbranched rays. All fin rays with odontodes; more developed odontodes on unbranched first ray.
Mesethmoid long; lateral expansion of anterior portion absent; mesethmoid ventral posterior process present. Nasal rectangular irregular bone curved laterally. Frontal wide, occluded from dorsal border of orbit. Orbit anteriorly delimited by dermal plate, dorsally by frontal bone, dorsolaterally by sphenotic, and ventrally by infraorbital series. Sphenotic quadrate in shape, contacting frontal bone anterolaterally, parieto-supraoccipital dorsally, infraorbital six ventrally, and pterotic-extrascapular posteriorly. Pterotic-extrascapular with large perforations. Parieto-supraoccipital wide and oval, contacting first predorsal plate posteriorly. Anterior contact of hyomandibula with metapterygoid and quadrate, and ventral with preopercle. Symphyseal cartilage between quadrate and hyomandibula. Anterior margin of quadrate articulation with anguloarticular. Dentary almost twice the size of anguloarticular. Autopalatine irregular, rod-like shape. Anterior margin of autopalatine articulation with maxilla and posterior contact posteriorly with vomer and metapterygoid. Preopercle long and partially exposed; anterior process reaching at least half of quadrate length. Suspensorium rectangular in overall shape. Three branchiostegal rays. Hypohyal anterior border straight, without anterior projection. Urohyal triangular and posterior margin rounded, with medial foramen. Anterohyal and posterohyal partially separated by cartilage. Anterior margin of anterohyal greatly expanded. Basibranchial 2, 3 and 4 present; basibranchial 2 and 3 elongated; basibranchial 2 equal to basibranchial 3; basibranchial 2 and 3 ossified and basibranchial 4 cartilaginous. Two hypobranchials; hypobranchial 1 ossified and hypobranchial 2 cartilaginous. Four epibranchials with similar size. Five ceratobranchials; ceratobranchial 1 with accessory flange; ceratobranchial 5 triangular; ceratobranchial teeth restricted to mesial area of plate. Upper pharyngeal plate club-shaped, completely covered with fine teeth. Vertebral count 39(1) and 40(1); five thin pleural ribs directly attached to centra 8, 9, 10, 11 and 12(1) and four thin pleural ribs directly attached to centra 9, 10, 11 and 12(1); parapophysis of complex vertebra well developed (two specimens).
FIGURE 3 |
Gular region and variation of abdominal plates in specimens, ventral view of Farlowella wuyjugu. A. MPEG 26178, 143.4 mm SL; B. INPA 59894, 128.9 mm SL; C. MPEG 12684, 125 mm SL.
Coloration in alcohol. Ground color of dorsum and head pale or dark brown. Light brown color with diffuse and scattered dark brown spots on predorsal portion, from tip of parieto-supraoccipital and extending to all plates. Five to six rounded spots between the second and third infraorbital, extending to opercle. One dark brown lateral stripe on each side, that runs from snout to caudal peduncle. Ventral portion of head brown; yellow between lower lip and anterior portion of anal fin. Dorsal profile in posterior portion of anal fin light brown with diffuse and scattered dark brown spots along the plates, same to dorsal portion, more delimited in some individuals. Upper lip with scattered chromatophores. Pectoral, dorsal, pelvic, and anal fin rays with hyaline membranes and pigmented brown rays, sometimes forming dark bands. First rays markedly dark. Caudal fin almost completely dark brown, membranes and rays pigmented, in some individuals with area of hyaline membrane (Fig. 4).
FIGURE 4 |
Caudal fin coloration of Farlowella wuyjugu. MPEG 31191, 119.9 mm SL.
Geographical distribution.Farlowella wuyjugu is known only from small, forest creeks near Juruti, Pará State, tributaries of rio Arapiuns, rio Tapajós in its lower portion, rio Amazon basin, Brazil (Fig. 5).
FIGURE 5 |
Geographic distribution of Farlowella wuyjugu in lower rio Tapajós. Star = holotype; circles = paratypes localities.
Etymology. The specific epithet refers to the combination of the words Wuy jugu, which is the self-denomination of indigenous people known in Brazil as Munduruku. This ethnic group is part of the Tupi trunk and they are located in different regions and territories in the states of Pará, Amazonas, and Mato Grosso. In the region of the lower Tapajós River, in recent years some communities in the process of their ethnic identity have recognized themselves as Munduruku (Ramos, 2022). A noun in apposittion.
Conservation status.Farlowella wuyjugu is known from four collection stations [igarapé Rio Branco (Fig. 6), igarapé Mutum, and igarapé São Francisco] in Juruti municipality, Pará State, Brazil. Using the GeoCAT we calculate the extent of occurrence (EOO) of the species in 4,921 km2, suggesting a threatened category of Endangered (EN). Farlowella wuyjugu is sampled in few localities in the Juruti municipality, impacted by a large bauxite extraction project, deteriorating their habitats. Following the recommendations by the IUCN (IUCN Standards and Petitions Committee, 2022), F. wuyjugu should be categorized as Nearly Threatened (NT), following criterions B2:EN (EOO < 5,000 km2), b(iii) (decline of quality of habitat by bauxite extraction).
FIGURE 6 |
Igarapé Rio Branco, type-locality of Farlowella wuyjugu.
Variation of abdominal plates within Farlowellawuyjugu. Abdominal plates are usually termed as lateral abdominal plates, which are transversely elongated plates between the pectoral-fin axilla and the pelvic-fin insertion, and midabdominal plates, which cover the abdomen between the lateral ones (Londoño-Burbano, Reis, 2021). The midabdominal plates, in Farlowella, can be absent or present and when present can be incomplete or complete. Ballen et al., (2016b) described Falowella mitoupiboBallen, Urbano-Bonilla & Zamudio, 2016 and proposed as diagnostic for the species an incomplete median disjunct row of abdominal plates, divided at the center by plates belonging to the lateral rows of abdominal plates (vs. two or three complete rows of abdominal plates or an incomplete median row of one or two plates anteriorly that never reach to the level of the prepelvic plate). Although the authors proposed this character as a diagnosis for the species, in recent examinations of the type material of F. mitoupibo, it was possible to observe two completes rows of abdominal plates in one specimen (M. Dopazo, pers. obs.). Farlowella wuyjugu have midabdominal plates and can be an incomplete or complete midabdominal series (Fig. 3). An incomplete midabdominal series can be a disjunct row as described for F. mitoupibo or an incomplete median row of plates anteriorly that do not reach to the level of the prepelvic plate (Figs. 3A, B). Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species group of Farlowella: two rows (F. acus (Kner, 1853) group and F. amazonumGünther, 1864 group) and three rows (F. curtirostra Myers, 1942 group, F. mariaelene Martín Salazar, 1964 group, F. nattereri group, F. knerii (Steindachner, 1882) group and unassigned species group). Although Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species groups of Farlowella, both states were found in F. wuyjugu and F. mitoupibo, rendering that character not be useful to differentiate groups because they are variable within Farlowella species. A phylogenetic analysis of the genus (including the species described here) is being carried out and aims to test if these characters (proposed by Retzer, Page, 1996) are in fact phylogenetically informative.
DISCUSSIONLondoño-Burbano, Reis (2021) recovered the tribe Farlowellini Fowler, 1958 including five genera, Lamontichthys Miranda Ribeiro, 1939, Pterosturisoma Isbrücker & Nijssen, 1978, Sturisoma Swainson, 1838, Sturisomatichthys Isbrücker & Nijssen, 1979 and Farlowella Eigenmann & Eigenmann, 1889. The authors defined two exclusive synapomorphies for the tribe: (1) nuchal plate articulated to lateral plates (char 175) and (2) the presence of gular plates (char 179). According to Londoño-Burbano, Reis (2021), gular plates are large, polygonal dermal plates covering the ventral surface of the head behind the lower lip. Character 175 was observed in F. wuyjugu, however, character 179 is not applicable to the new species because of the lack of gular plates. Almost twenty years after the publication of the study by Retzer, Page (1996). Farlowella was proposed as a monophyletic group by Londoño-Burbano, Reis (2021) with 11 morphological and 38 molecular synapomorphies. Of the eleven morphological synapomorphies, four were considered exclusive for the genus: (1) number of branchiostegal rays fewer than four (char 109); (2) straight and upright lamina on neural spine on the sixth vertebra for articulation with ventral surface of parieto-supraoccipital (char 114); (3) absence of pleural rib associated to the seventh vertebra (char 117); (4) short anteriormost paraneural spines (char 129). These character states were all observed in F. wuyjugu supporting the species as a member of the genus. Despite the high number of morphological characters and the number of terminals used in the analysis by the authors, there are many high homoplastic characters and not useful for a diagnosis at the species level.
Other Farlowella species are also identified for the rio Tapajós basin (F. gr. amazonum, F. cf. oxyrryncha, F. schreitmuelleri Arnold, 1936, and F. sp.; M. Dopazo, pers. obs.). Species with type locality in or near the region are F. amazonum (Santarém, Pará State), F. gladiolusGünther, 1864 (rio Cupari, rio Tapajós basin, Amazon River drainage, Pará State), and F. schreitmuelleri (lower Amazon River basin, Santarém, Pará State), but they differ from F. wuyjugu mainly by the number of lateral series of plate rows on anterior region of body (four vs. five). Farlowella amazonum and F. gladiolus were described in the same work by Günther, (1864). In the review of the genus by Retzer, Page (1996), F. gladiolus was placed in the synonymy with F. amazonum, however, Covain et al., (2016) recognized the former as a valid species. There are several taxonomic issues regarding the validity of Farlowella species and their delimitation. These questions are being addressed in an ongoing taxonomic review (by MD and MRB) of the genus. Our description of F. wuyjugu contributes to the knowledge of the rio Arapiuns and to the understanding of the ichthyofauna of the rio Tapajós basin.
Comparative material examined.Farlowella acus: Colombia: MPUJ 2834, 1, 183.6 mm SL; MPUJ 2842, 1, 133.3 mm SL; MPUJ 2955, 1, 50.1 mm SL: MPUJ 7320,1 124.1 mm SL; MPUJ 9287, 1, 122.5 mm SL; MPUJ 10915, 1, 116.9 mm SL; MPUJ 11158, 1, 130.4 mm SL; MPUJ 13270, 1, 38.6 mm SL: MPUJ 16876, 1, 76 mm SL; Venezuela: ANSP 130038, 20, 90.6–149.7 mm SL; MZUSP 147, 2, 108.4–123.8 mm SL; Farlowella cf. altocorpus: Brazil: INPA 3034, 49, 64.2–155.6 mm SL; INPA 3035, 16, 58–148.6 mm SL; Farlowella amazonum: Brazil: LIA 7233, 1, 84.7 mm SL; LIA 7235, 64.8–198.5 mm SL; LIA 7236, 4, 69.2–92,5 mm SL; LBP 4344, 1, 82.9 mm SL; LBP 10860, 3, 111.0–144.7 mm SL; LBP 11118, 1, 132.2 mm SL; LBP 12117, 5, 47.4–147.2 mm SL; LBP 15179, 1, 82.9 mm SL; LBP 17994, 3, 70.7–121.81 mm SL; LBP 20432, 1, 110.1 mm SL; LBP 20964, 2, 67.5–113.1 mm SL; LBP 21208, 4, 69.5–121.7 mm SL; LBP 21230, 1, 142.1 mm SL; LBP 22348, 13, 54.9–203.6 mm SL; LBP 22488, 1, 169.2 mm SL; MCP 44240, 6, 163.8–190.7 mm SL; MCP 50059, 83.6–176.4 mm SL; MNRJ 762, 3, 130.1–161.2 mm SL; MNRJ 35534, 15, 79.9–166.1 mm SL, 3 cs; MNRJ 35535, 3, 176.3–161.3 mm SL; MNRJ 35536, 2, 76.3–176.8 mm SL; MNRJ 35537, 2, 99.7–179.9 mm SL; MNRJ 39040, 8, 52.1–73.7 mm SL; MNRJ 39249, 1, 66.6 mm SL; MNRJ 39270, 6, 34.4–66.8 mm SL; MPEG 3072, 2, 71,7–146.2 mm SL; MPEG 9008, 4, 147–182.3 mm SL; MPEG 13290, 5, 157.9–180.3 mm SL; MPEG 17077, 1, 50.8 mm SL; MPEG 19827, 1, 182.2 mm SL; MPEG 19945, 1, 123.8 mm SL; MPEG 23942, 2, 139–175.4 mm SL; MPEG 23726, 2, 166.4–172.5 mm SL; MPEG 24470, 1, 129.2 mm SL; MPEG 24471, 2, 166.3–74 mm SL; MPEG 30598, 5, 118.3–151.1 mm SL; MPEG 30931, 1, 104.2 mm SL; MPEG 30936, 1, 109.7 mm SL; MZUSP 23416, 5, 35.9–139.2 mm SL; MZUSP 27717, 1, 115.8 mm SL; MZUSP 121244, 1, 207.0 mm SL; UFRGS 21710, 1, 80.5 mm SL; Peru: ANSP 191818, 2, 172.7–179.6 mm SL; ANSP 199910, 1, 146.1 mm SL; Farlowella azpelicuetae: Argentina: MZUSP 123935, paratype, 80.8 mm SL; MZUSP 123936, 2, paratypes, 79.8–165.9 mm SL; Farlowella gianetti: Brazil: MZUSP 95564, holotype, 114.4 mm SL; MZUSP 97022, paratypes, 94.1–118.6 mm SL; Farlowella cf. hahni: Brazil: MZUEL 9037, 5, 56.6–131 mm SL; MZUEL 9669, 1, 47.2 mm SL; NUP 374, 6, 78.1–161.7 mm SL; NUP 818, 5, 127.6–140 mm SL; NUP 819, 10, 89.3–156.2 mm SL; NUP 1450, 1, 111.7 mm SL; NUP 1496, 5, 95.7–177.8 mm SL; NUP 2849, 1, 128.4 mm SL; NUP 4029, 2, 151.1–162.2 mm SL; NUP 4525, 1, 130.7 mm SL; NUP 4728, 5, 129.4–148 mm SL; NUP 7867, 2, 134.7–140.3 mm SL; NUP 11443, 1, 109.5 mm SL; NUP 13303, 2, 103.2–129.7 mm SL; NUP 14747, 1, 125.6 mm SL; NUP 16978, 2, 133.8–149.8 mm SL; Farlowella hasemani: Brazil: INPA 3912, 190.8 mm SL; Farlowella henriquei: Brazil: INPA 3012, 2, 68.8–111 mm SL; INPA 3030, 1, 170.3 mm SL; INPA 3911, 147.9–153.1 mm SL; INPA 3913, 1, 180.7; INPA 34545, 3, 83.6–160.5 mm SL; MZUSP 2159, holotype, 165.7 mm SL; Farlowella isbruckeri: Brazil: MZUSP 27704, paratype, 134.8 mm SL; Farlowella jauruensis: Brazil: MZUSP 59457, 2, 58.3–57.3 mm SL; MZUSP 58485, 1, 77.2 mm SL; MZUSP 115560, 1, 81.4 mm SL; Farlowella knerii: Ecuador: ANSP 130435, 2, 21.4–73.3 mm SL; ANSP 130436, 1, 123.3 mm SL; Farlowella latisoma: Brazil: MNRJ 761, holotype, 179.3 mm SL, synonymy of Farlowella schreitmuelleri; Farlowella mariaelenae: Venezuela: ROM 94123, 2, 67.2–81.8 mm SL; Farlowella mitoupibo: Colombia: MPUJ 8481, holotype, 203.7 mm SL; MPUJ 8479, 1, paratype, 112.6 mm SL; MPUJ 8480, paratype, 5, 65.7–170 mm SL; MPUJ 8482, paratype, 109.4 mm SL; MPUJ 8483, paratype, 1, 163.1 mm SL; MPUJ 8484, paratype, 1, 112.5 mm SL; Farlowella myriodon: Peru: MZUSP 15328, holotype, 154 mm SL; MZUSP 15332, paratype, 134.2 mm SL; MZUSP 15342, paratype, 92.6 mm SL; Farlowella nattereri: Brazil: LBP 10568, 3, 80.7–92.4 mm SL; LBP 18192, 6, 47.5–117.5 mm SL; LBP 18526, 1, 189.9 mm SL; LBP 18580, 3, 102.9–164.5 mm SL; LBP 26628, 7, 185.0–208.6 mm SL; MNRJ 3732, 2, 166.9–168.2 mm SL; MNRJ 37080, 1, 135.7 mm SL; UFRO–ICT 6731, 2, 96.4–104.6 mm SL; UFRGS 26186, 1, 147.7 mm SL; Colombia: ROM 107219, 3, 90.3–213 mm SL; Peru: LBP 22594, 1, 132.3 mm SL; ROM 64063, 6, 42.9–129.8 mm SL; Farlowella aff. nattereri: Brazil: INPA 1637, 1, 117.8 mm SL; INPA 1963, 2, 78.7–146.1 mm SL; INPA 2017, 1, 87.5 mm SL; INPA 2808, 1, 171.8 mm SL; INPA 3916, 1, 95 mm SL; INPA 4839, 1, 184.5 mm SL; INPA 12945, 1, 162.5 mm SL; INPA 16763, 1, 52 mm SL; INPA 43891, 1, 199.1 mm SL; Guyana: INPA 58225, 2, 135.6–52.7 mm SL; ROM 97162, 1, 112.3 mm SL; Farlowella oliveirae Miranda Ribeiro, 1939: MNRJ 757, holotype, 111.8 mm SL, synonymy of Farlowella amazonum; Farlowella aff. oxyrryncha: Brazil: INPA 12940, 6, 61–155.2 mm SL; INPA 12941, 1, 60.5 mm SL; INPA 29869, 5, 29.9–105.1 mm SL; INPA 31038, 1, 100.3 mm SL; MZUEL 6713, 1, 103 mm SL; Farlowella cf. oxyrryncha: Brazil: INPA 1645,1, 86.4 mm SL; INPA 8159, 3, 61.9–151.6 mm SL; INPA 10371, 21, 72.33–188 mm SL; INPA 12964, 1, 56.3 mm SL; INPA 14001, 1, 159.2; INPA 20796, 1, 134.4 mm SL; INPA 27505, 21, 23.9–129.3 mm SL; INPA 37694, 1, 75 mm SL; INPA 53229, 1, 199.8 mm SL; INPA 54977, 1, 110 mm SL; INPA 58662, 1, 170.5 mm SL; MCP 32735, 1, 83 mm SL; MCP 36623, 7, 51.6–112.7 mm SL; MCP 46138, 1, 103 mm SL; MPEG 13083, 3, 116.4–127 mm SL; MPEG 28662, 5, 73.7–178.5 mm SL; MPEG 30901, 1, 103.7 mm SL; UFRGS 12165, 4, 105,5–97.7 mm SL; UFRGS 12325, 5, 49.8–133.6 mm SL; UFRGS 21842, 1, 100.3 mm SL; MNRJ 23380, 1, 115.4 mm
New species of Farlowella (Siluriformes: Loricariidae) from the rio Tapajós basin, Pará, Brazil
Manuela DopazoWolmar B. WosiackiMarcelo R. BrittoABOUT THE AUTHORS
- Abstract
- Resumo
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- ACKNOWLEDGEMENTS
- REFERENCES
- ADDITIONAL NOTES
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Keywords:
Amazon; Armored catfish; Biodiversity; Loricariinae; Taxonomy
ResumoUma nova espécie de cascudo-graveto Farlowella é descrita de pequenos igarapés do baixo rio Tapajós, no Estado do Pará, norte do Brasil. A nova espécie é distinta de todas as suas congêneres por uma região gular nua (vs. região gular com placas) e de muitas congêneres pela presença de cinco fileiras de placas laterais na região anterior do corpo (vs. quatro). A nova espécie apresenta variação na série de placas abdominais e é feita uma discussão sobre a variação das placas abdominais dentro de Farlowella e comentários sobre caracteres sinapomórficos em Farlowellini.
Palavras-chave:
Amazônia; Biodiversidade; Cascudo; Loricariinae; Taxonomia
INTRODUCTIONThe genus FarlowellaEigenmann & Eigenmann, 1889 is a component of the freshwater fish fauna of the Neotropics. With 32 valid species, Farlowella is the second-most species-rich genus of Loricariinae, a sub-family comprised of 262 valid species in 31 genera (Delgadillo et al., 2021; Londoño-Burbano, Reis, 2021; Fricke et al., 2023). Farlowella representatives are widely distributed in the main cis-Andean South America river drainages and trans-Andean Maracaibo and Magdalena river basins (Terán et al., 2019). They are easily distinguished by having a pronounced rostrum, a thin, elongated, brown body with two longitudinal bands that extend from the tip of the rostrum to the caudal peduncle (Covain, Fisch-Muller, 2007), resembling dry twigs or sticks, which justifies the popular name stick catfishes.
The first taxonomic study was the description of the genus Acestra by Kner, (1853), with the first species described: Acestra acus and A. oxyrryncha, but without designating the type species of the genus, until A. acus was determined by Bleeker, (1862). However, Acestra was already occupied in Hemiptera (Dallas, 1852) and the name Farlowella was then replaced by Eigenmann, Eigenmann, (1889). From the end of the 19th century, several species were described, totaling 37 names that remained for almost a century, when Retzer, Page (1996) revised the genus based on characters of external morphology. This was the last revision of its species, as well as the first exclusive hypothesis of the phylogenetic relationships of the genus. In that study, the authors performed a phylogenetic analysis with morphological data including only one external group, Aposturisoma myriodon Isbrücker, Britski, Nijssen & Ortega, 1983 (= Farlowella myriodon), that was used to root the tree; the monophyly of the genus, and species relationships were not actually tested. The authors also proposed six species groups and six species were considered as incertae sedis.
Recently, Londoño-Burbano, Reis (2021), based on combined molecular and morphological phylogenetic analysis, formally recognized Aposturisoma myriodon as a member of Farlowella to assign the monophyly of the genus. Although A. myriodon is phenotypically different from Farlowella, this configuration had already been recovered by Covain et al., (2016). Based on the review of Farlowella material deposited in different collections and on the examination of material collected in the river near the confluence with rio Tapajós, in its lower portion, we identified a new species of Farlowella, which is described herein.
MATERIAL AND METHODSMeasurements were taken point to point with digital calipers. Measurements are expressed as percents of the standard length (SL), except subunits of head, which are expressed as percents of the head length (HL). Measurements follow Boeseman, (1971), except measurement of distance from pectoral-fin origin to pelvic-fin origin that follow Retzer, Page (1996), plus minimum width of snout (minimum width at the tip of snout) (Fig. 1A), distance between cleithral processes (between the humeral processes of the cleithrum) (Fig. 1B) and maximum width of snout (maximum width in transverse line from the posterior edge of the ventral plate before mouth) (Fig. 1C). Counts and nomenclature of lateral plate series follow Ballen et al., (2016a). Osteological nomenclature follows Paixão, Toledo-Piza, (2009), except for parieto-supraoccipital instead of supraoccipital (Arratia, Gayet, 1995), pterotic-extraescapular instead of pterotic-supracleithrum (Slobodian, Pastana, 2018). Vertebral counts include only free centra, with the compound caudal centrum (preural 1+ ural 1) counted as a single element. Cleared and stained (cs) specimens were prepared according to the methods of Taylor, Van Dyke, (1985). Numbers in parentheses following meristic counts correspond to number of specimens having that count, and those indicated by an asterisk (*) belong to the holotype. Map was generated in the QGIS 3.14.16 program. Institutional abbreviations follow Sabaj, (2022). The estimated Extent of Occurrence (EOO) and Area of Occupation (AOO) of the species was calculated using the web portal of the Geospatial Conservation Assessment Tool (GeoCAT: http://geocat.kew.org/) and the categories and criteria of conservation status of species followed IUCN (IUCN Standards and Petitions Committee, 2022).
FIGURE 1 |
Additional measures used in this study. A. Minimum width of snout; B. Distance between cleithral processes; and C. Maximum width of snout.
RESULTSFarlowella wuyjugu, new species
urn:lsid:zoobank.org:act:FA22FB00-B26F-45C0-A121-2BD8FB00B523
(Figs. 2–3; Tab. 1)
Holotype. MPEG 26178, 143.4 mm SL, Brazil, Pará State, Juruti municipality, lower rio Tapajós, rio Amazon basin, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça.
Paratypes. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. INPA 59894, 2, 124.8–128.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MNRJ 53691, 2, 127.3–130.9 mm SL, same locality as INPA 59894. MPEG 10062, 5, 112.0–121.6 mm SL, same locality as INPA 59894, 3 Mar 2006, L. F. A. Montag. MPEG 12865, 5, 90.9–123.2 mm SL, same locality as INPA 59894, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 15900, 12, 2 cs, 97.6–136.5 mm SL, same locality as INPA 59894, 8 Sep 2002, W. B. Wosiacki. MPEG 10857, 5, 111.7–128.2 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Aug 2006, A. Hercos. MPEG 32191, 4, 94.3–133.9 mm SL, same locality as MPEG 10857, 14 Sep 2014, M. B. Mendonça. MPEG 12684, 5, 1 cs, 122.8–144.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°50’13.8”W, 14 Dec 2006, L. F. A. Montag.
Non-types. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. MPEG 10055, 4, 102.9–124.3 mm SL, MPEG 10062, 13, 70.0–109.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 3 Mar 2006, L. F. A. Montag. MPEG 10851, 1, 119.2 mm SL, MPEG 10852, 3, 79.5–116.1 mm SL, MPEG 10853, 1, 121.9 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10855, 4, 46.7–88.7 mm SL, MPEG 10856, 7, 54.2–108.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10857, 11, 65.1–145.8 mm SL, MPEG 10858, 2, 106.2–112.8 mm SL, MPEG 10859, 4, 64.4–128.3 mm SL, MPEG 10861, 1, 113.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10860, 1, 128.6 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10862, 3, 49.6–54.6 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10956, 1, 26.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 12491, 4, 18.6–45.8 mm SL, igarapé Mutum, 02°36’44.8”S 56°11’37.3”W, 9 Sep 2002, W. B. Wosiacki. MPEG 12865, 4, 69.8–93.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 13040, 2, 35.7–38.4 mm SL, MPEG 13043, 2, 20.6–30 mm SL, MPEG 13050, 2, 11.0–118.4 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, L. F. A. Montag. MPEG 13041, 1, 56.3 mm SL, MPEG 13044, 5, 56.8–93.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 12 Dec 2006, L. F. A. Montag. MPEG 13042, 3, 48.1–45.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13045, 1, 92.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13046, 1, 101.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 Dec 2006, L. F. A. Montag. MPEG 13048, 5, 50.2–80.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 Dec 2006, L. F. A. Montag. MPEG 13731, 2, 63.9–69.4 mm SL, MPEG 14143, 7, 61.9–136.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 May 2007, A. Hercos. MPEG 14271, 1, 42.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 27 Nov 2007, A. Hercos. MPEG 14711, 13, 46.2–126.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 May 2007, A. Hercos. MPEG 15900, 8, 56.6–95.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MPEG 16955, 1, 120.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’33.2”S 56°11’33.4”W, 19 Feb 2008, W. B. Wosiacki. MPEG 26172, 13, 71.8–129.8 mm SL, MPEG 26173, 4, 61.5–94.5 mm SL, MPEG 26333, 1, 86.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 28 Nov 2012, M. B. Mendonça. MPEG 26179,19, 43.5–156.4 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça. MPEG 29996, 2, 112.7–117.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 6 Dec 2013, M. B. Mendonça. MPEG 26997, 9, 100.5–129.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 7 Dec 2013, M. B. Mendonça. MPEG 26998, 1, 88.9 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 11 Dec 2013, M. B. Mendonça. MPEG 26999, 5, 51.9–138.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 12 Dec 2012, M. B. Mendonça. MPEG 32191, 4, 93.7–136.6 mm SL, MPEG 32192, 2, 55.6–115.1 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Sep 2014, M. B. Mendonça. MPEG 32193, 15, 32.9–124.2 mm SL, MPEG 32194, 14, 61.4–127.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 22 Sep 2014, M. B. Mendonça. MPEG 32195, 1, 135.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 18 Sep 2014, M. B. Mendonça. MPEG 32507, 72.4–113.1 mm S, MPEG 32508, 11, 49.0–116.5 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 20 Mar 2015, M. B. Mendonça.
FIGURE 2 |
Dorsal, lateral and ventral view of Farlowella wuyjugu, holotype, 143.4 mm SL, MPEG 26178, Brazil, Pará State, Juruti municipality, igarapé Rio Branco, lower rio Tapajós, rio Amazon basin.
Diagnosis.Farlowella wuyjugu can be diagnosed from its congeners by lack of plates in gular region (vs. gular plates present) (Fig. 3). The new species can be distinguished from its congeners, except Farlowella altocorpus Retzer, 2006, F. azpelicuetae Terán, Ballen, Alonso, Aguilera & Mirande, 2019, F. gianetii Ballen, Pastana & Peixoto, 2016, F. gracilis Regan, 1904, F. guarani Delgadillo, Maldonado & Carvajal-Vallejos, 2021, F. hasemani Eigenmann & Vance, 1917, F. isbrueckeri Retzer & Page, 1997, F. jauruensis Eigenmann & Vance, 1917, F. myriodon, F. nattereri Steindachner, 1910, and F. odontotumulusRetzer & Page, 1997, by having five lateral series of plate rows on anterior region of body (vs. four). Additionally, F. wuyjugu differs from F. altocorpus and F. azpelicuatae by having a smaller body width at dorsal origin (4.3–5.5 vs. 6.4–8.1% SL); from F. gianetti by number of caudal-fin rays (i,11,i or i,12,i vs. i,10,i); from F. gracilis by having head triangular in dorsal view (vs. head square); from F. guarani by interorbital width (12.0–16.0 vs. 28.6–44% HL) and eye diameter (3.6–5.8 vs. 6.6–13.3% HL); from F. hasemani by all fin rays uniformly pigmented (vs. fin rays not pigmented); from F. isbruckeri and F. odontotumulus by having the ventromedian row of anterior plates keeled (vs. ventromedian row of anterior plates unkeeled); from F. jauruensis by having five branched pelvic-fin rays (vs. four branched pelvic-fin rays); from F. myriodon by having dark brown lateral stripe on each side of snout (vs. absence of such stripe, snout completely dark); and from F. nattereri by having a short pectoral fin, not reaching the pelvic-fin base (vs. long pectoral fin, reaching the pelvic-fin base).
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TABLE 1 |
Morphometrics of Farlowella wuyjugu, new species. Values as percents of standard length (SL) and head length (HL) for holotype and 38 paratypes. n = number of specimens, SD = Standard deviation.
Description. Dorsal, lateral, and ventral views of holotype in Fig. 2. Morphometric and meristic data for holotype and paratypes summarized in Tab. 1. Body slender and very elongated, completely covered by dermal plates, except in gular portion. Head triangular and elongate in dorsal and ventral views. Rostrum slender and flat in ventral view. Orbit circular, dorsolaterally placed, visible in dorsal view and not visible in ventral view. Preorbital ridge present. Mouth ventral. Dorsal profile of head concave from snout tip to anterior margin of nares, relatively straight to convex from point to posterior margin of nares to posterior margin of parieto-supraoccipital and slightly concave to dorsal-fin origin. Posterior profile of margin of dorsal-fin origin slightly concave and straight profile to end of caudal peduncle. Ventral profile slightly straight from tip of snout to anal-fin origin, slightly concave in anal-fin base and straight profile to end of caudal peduncle.
Mouth ovoid, lower lip longer than upper lip; wide oval papillae on upper lip and round papillae on lower lip, decreasing in size from oral aperture to lip margin; lip margin papillose. Bicuspid slender teeth, each premaxilla with 22(2), 23*(1), 29(1), 31(1), 33(1), 36(1), 37(3), 39(1), 40(2), 41(1), 42(3), 43(2), 44(1), 46(3), 47(4), 48(4), 49(4), 51(2), 53(1) or 55(1) teeth and each dentary with 18*(3), 22(1), 23(1), 26(2), 28(1), 29(2), 30(2), 32(3), 33(3), 34(1), 35(4), 36(3), 37(1), 38(4), 39(2), 40(2), 41(1), 42(1) or 43(2) teeth; premaxilla larger than dentary. Two maxillary barbels small and projecting slightly from mouth margin.
Five lateral plate rows on body, with 31(6), 32*(30) or 33(3) dorsal plates; 6(1), 7*(5), 8(23) or 9(10) dorsomedian plates; 7(1), 8*(5), 9(20) or 10(13) median plates; 14*(7), 15(27) or 16(5) ventromedian plates; 35(3), 36(7), 37*(15), 38(9), 39(3) or 40(2) ventral plates; 5(14), 6*(18), 7(6) or 8(1) dorsomedian+median plates; 18(12), 19(20) or 20*(7) coalescent plates; 8*(39) predorsal plates; 23(6), 24*(30) or 25(3) postdorsal plates; 20(2), 21(14), 22*(21), 23(1) or 24(1) postanal plates; 2 plates at the base of caudal fin and one preanal plate. Abdomen covered with two lateral rows with 6(6), 7*(19), 8(11), 9(2), 11(1) lateral abdominal plates (left) and 6(10), 7*(14), 8(8) or 9(7) lateral abdominal plates (right), and one midabdominal incomplete (23)* row or when complete (16) row with 2(1), 3(2), 4*(2), 5(1), 6(5), 7(7), 8(7), 9(3), 10(3), 11(2), 12(3), 13(2) or 16(1) midabdominal plates.
Lateral line complete; reaching up to last caudal peduncle coalesced plate. Preopercular canal passing through infraorbital six with two pores. Terminal exit of parietal branch in frontal bone curved. Canal-bearing cheek plate in ventral position. Nasal slightly curved in anterior portion with pore opening laterally.
Pectoral-fin rays i,6*(39); posterior margin slightly concave; unbranched ray longest. Dorsal-fin rays i,6*(39); posterior margin straight to slightly concave; three* or four plates along its base; unbranched ray longest. Pelvic-fin rays i,5*(39); posterior margin straight; unbranched ray longest. Anal-fin rays i,5*(39); posterior margin straight to slightly concave; unbranched ray longest; three* or four plates along its base. Caudal-fin rays i,11,i(2) or i,12,i*(37); posterior margin deeply concave; dorsal and ventral lobes similar in size; filaments on upper and lower unbranched rays. All fin rays with odontodes; more developed odontodes on unbranched first ray.
Mesethmoid long; lateral expansion of anterior portion absent; mesethmoid ventral posterior process present. Nasal rectangular irregular bone curved laterally. Frontal wide, occluded from dorsal border of orbit. Orbit anteriorly delimited by dermal plate, dorsally by frontal bone, dorsolaterally by sphenotic, and ventrally by infraorbital series. Sphenotic quadrate in shape, contacting frontal bone anterolaterally, parieto-supraoccipital dorsally, infraorbital six ventrally, and pterotic-extrascapular posteriorly. Pterotic-extrascapular with large perforations. Parieto-supraoccipital wide and oval, contacting first predorsal plate posteriorly. Anterior contact of hyomandibula with metapterygoid and quadrate, and ventral with preopercle. Symphyseal cartilage between quadrate and hyomandibula. Anterior margin of quadrate articulation with anguloarticular. Dentary almost twice the size of anguloarticular. Autopalatine irregular, rod-like shape. Anterior margin of autopalatine articulation with maxilla and posterior contact posteriorly with vomer and metapterygoid. Preopercle long and partially exposed; anterior process reaching at least half of quadrate length. Suspensorium rectangular in overall shape. Three branchiostegal rays. Hypohyal anterior border straight, without anterior projection. Urohyal triangular and posterior margin rounded, with medial foramen. Anterohyal and posterohyal partially separated by cartilage. Anterior margin of anterohyal greatly expanded. Basibranchial 2, 3 and 4 present; basibranchial 2 and 3 elongated; basibranchial 2 equal to basibranchial 3; basibranchial 2 and 3 ossified and basibranchial 4 cartilaginous. Two hypobranchials; hypobranchial 1 ossified and hypobranchial 2 cartilaginous. Four epibranchials with similar size. Five ceratobranchials; ceratobranchial 1 with accessory flange; ceratobranchial 5 triangular; ceratobranchial teeth restricted to mesial area of plate. Upper pharyngeal plate club-shaped, completely covered with fine teeth. Vertebral count 39(1) and 40(1); five thin pleural ribs directly attached to centra 8, 9, 10, 11 and 12(1) and four thin pleural ribs directly attached to centra 9, 10, 11 and 12(1); parapophysis of complex vertebra well developed (two specimens).
FIGURE 3 |
Gular region and variation of abdominal plates in specimens, ventral view of Farlowella wuyjugu. A. MPEG 26178, 143.4 mm SL; B. INPA 59894, 128.9 mm SL; C. MPEG 12684, 125 mm SL.
Coloration in alcohol. Ground color of dorsum and head pale or dark brown. Light brown color with diffuse and scattered dark brown spots on predorsal portion, from tip of parieto-supraoccipital and extending to all plates. Five to six rounded spots between the second and third infraorbital, extending to opercle. One dark brown lateral stripe on each side, that runs from snout to caudal peduncle. Ventral portion of head brown; yellow between lower lip and anterior portion of anal fin. Dorsal profile in posterior portion of anal fin light brown with diffuse and scattered dark brown spots along the plates, same to dorsal portion, more delimited in some individuals. Upper lip with scattered chromatophores. Pectoral, dorsal, pelvic, and anal fin rays with hyaline membranes and pigmented brown rays, sometimes forming dark bands. First rays markedly dark. Caudal fin almost completely dark brown, membranes and rays pigmented, in some individuals with area of hyaline membrane (Fig. 4).
FIGURE 4 |
Caudal fin coloration of Farlowella wuyjugu. MPEG 31191, 119.9 mm SL.
Geographical distribution.Farlowella wuyjugu is known only from small, forest creeks near Juruti, Pará State, tributaries of rio Arapiuns, rio Tapajós in its lower portion, rio Amazon basin, Brazil (Fig. 5).
FIGURE 5 |
Geographic distribution of Farlowella wuyjugu in lower rio Tapajós. Star = holotype; circles = paratypes localities.
Etymology. The specific epithet refers to the combination of the words Wuy jugu, which is the self-denomination of indigenous people known in Brazil as Munduruku. This ethnic group is part of the Tupi trunk and they are located in different regions and territories in the states of Pará, Amazonas, and Mato Grosso. In the region of the lower Tapajós River, in recent years some communities in the process of their ethnic identity have recognized themselves as Munduruku (Ramos, 2022). A noun in apposittion.
Conservation status.Farlowella wuyjugu is known from four collection stations [igarapé Rio Branco (Fig. 6), igarapé Mutum, and igarapé São Francisco] in Juruti municipality, Pará State, Brazil. Using the GeoCAT we calculate the extent of occurrence (EOO) of the species in 4,921 km2, suggesting a threatened category of Endangered (EN). Farlowella wuyjugu is sampled in few localities in the Juruti municipality, impacted by a large bauxite extraction project, deteriorating their habitats. Following the recommendations by the IUCN (IUCN Standards and Petitions Committee, 2022), F. wuyjugu should be categorized as Nearly Threatened (NT), following criterions B2:EN (EOO < 5,000 km2), b(iii) (decline of quality of habitat by bauxite extraction).
FIGURE 6 |
Igarapé Rio Branco, type-locality of Farlowella wuyjugu.
Variation of abdominal plates within Farlowellawuyjugu. Abdominal plates are usually termed as lateral abdominal plates, which are transversely elongated plates between the pectoral-fin axilla and the pelvic-fin insertion, and midabdominal plates, which cover the abdomen between the lateral ones (Londoño-Burbano, Reis, 2021). The midabdominal plates, in Farlowella, can be absent or present and when present can be incomplete or complete. Ballen et al., (2016b) described Falowella mitoupiboBallen, Urbano-Bonilla & Zamudio, 2016 and proposed as diagnostic for the species an incomplete median disjunct row of abdominal plates, divided at the center by plates belonging to the lateral rows of abdominal plates (vs. two or three complete rows of abdominal plates or an incomplete median row of one or two plates anteriorly that never reach to the level of the prepelvic plate). Although the authors proposed this character as a diagnosis for the species, in recent examinations of the type material of F. mitoupibo, it was possible to observe two completes rows of abdominal plates in one specimen (M. Dopazo, pers. obs.). Farlowella wuyjugu have midabdominal plates and can be an incomplete or complete midabdominal series (Fig. 3). An incomplete midabdominal series can be a disjunct row as described for F. mitoupibo or an incomplete median row of plates anteriorly that do not reach to the level of the prepelvic plate (Figs. 3A, B). Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species group of Farlowella: two rows (F. acus (Kner, 1853) group and F. amazonumGünther, 1864 group) and three rows (F. curtirostra Myers, 1942 group, F. mariaelene Martín Salazar, 1964 group, F. nattereri group, F. knerii (Steindachner, 1882) group and unassigned species group). Although Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species groups of Farlowella, both states were found in F. wuyjugu and F. mitoupibo, rendering that character not be useful to differentiate groups because they are variable within Farlowella species. A phylogenetic analysis of the genus (including the species described here) is being carried out and aims to test if these characters (proposed by Retzer, Page, 1996) are in fact phylogenetically informative.
DISCUSSIONLondoño-Burbano, Reis (2021) recovered the tribe Farlowellini Fowler, 1958 including five genera, Lamontichthys Miranda Ribeiro, 1939, Pterosturisoma Isbrücker & Nijssen, 1978, Sturisoma Swainson, 1838, Sturisomatichthys Isbrücker & Nijssen, 1979 and Farlowella Eigenmann & Eigenmann, 1889. The authors defined two exclusive synapomorphies for the tribe: (1) nuchal plate articulated to lateral plates (char 175) and (2) the presence of gular plates (char 179). According to Londoño-Burbano, Reis (2021), gular plates are large, polygonal dermal plates covering the ventral surface of the head behind the lower lip. Character 175 was observed in F. wuyjugu, however, character 179 is not applicable to the new species because of the lack of gular plates. Almost twenty years after the publication of the study by Retzer, Page (1996). Farlowella was proposed as a monophyletic group by Londoño-Burbano, Reis (2021) with 11 morphological and 38 molecular synapomorphies. Of the eleven morphological synapomorphies, four were considered exclusive for the genus: (1) number of branchiostegal rays fewer than four (char 109); (2) straight and upright lamina on neural spine on the sixth vertebra for articulation with ventral surface of parieto-supraoccipital (char 114); (3) absence of pleural rib associated to the seventh vertebra (char 117); (4) short anteriormost paraneural spines (char 129). These character states were all observed in F. wuyjugu supporting the species as a member of the genus. Despite the high number of morphological characters and the number of terminals used in the analysis by the authors, there are many high homoplastic characters and not useful for a diagnosis at the species level.
Other Farlowella species are also identified for the rio Tapajós basin (F. gr. amazonum, F. cf. oxyrryncha, F. schreitmuelleri Arnold, 1936, and F. sp.; M. Dopazo, pers. obs.). Species with type locality in or near the region are F. amazonum (Santarém, Pará State), F. gladiolusGünther, 1864 (rio Cupari, rio Tapajós basin, Amazon River drainage, Pará State), and F. schreitmuelleri (lower Amazon River basin, Santarém, Pará State), but they differ from F. wuyjugu mainly by the number of lateral series of plate rows on anterior region of body (four vs. five). Farlowella amazonum and F. gladiolus were described in the same work by Günther, (1864). In the review of the genus by Retzer, Page (1996), F. gladiolus was placed in the synonymy with F. amazonum, however, Covain et al., (2016) recognized the former as a valid species. There are several taxonomic issues regarding the validity of Farlowella species and their delimitation. These questions are being addressed in an ongoing taxonomic review (by MD and MRB) of the genus. Our description of F. wuyjugu contributes to the knowledge of the rio Arapiuns and to the understanding of the ichthyofauna of the rio Tapajós basin.
Comparative material examined.Farlowella acus: Colombia: MPUJ 2834, 1, 183.6 mm SL; MPUJ 2842, 1, 133.3 mm SL; MPUJ 2955, 1, 50.1 mm SL: MPUJ 7320,1 124.1 mm SL; MPUJ 9287, 1, 122.5 mm SL; MPUJ 10915, 1, 116.9 mm SL; MPUJ 11158, 1, 130.4 mm SL; MPUJ 13270, 1, 38.6 mm SL: MPUJ 16876, 1, 76 mm SL; Venezuela: ANSP 130038, 20, 90.6–149.7 mm SL; MZUSP 147, 2, 108.4–123.8 mm SL; Farlowella cf. altocorpus: Brazil: INPA 3034, 49, 64.2–155.6 mm SL; INPA 3035, 16, 58–148.6 mm SL; Farlowella amazonum: Brazil: LIA 7233, 1, 84.7 mm SL; LIA 7235, 64.8–198.5 mm SL; LIA 7236, 4, 69.2–92,5 mm SL; LBP 4344, 1, 82.9 mm SL; LBP 10860, 3, 111.0–144.7 mm SL; LBP 11118, 1, 132.2 mm SL; LBP 12117, 5, 47.4–147.2 mm SL; LBP 15179, 1, 82.9 mm SL; LBP 17994, 3, 70.7–121.81 mm SL; LBP 20432, 1, 110.1 mm SL; LBP 20964, 2, 67.5–113.1 mm SL; LBP 21208, 4, 69.5–121.7 mm SL; LBP 21230, 1, 142.1 mm SL; LBP 22348, 13, 54.9–203.6 mm SL; LBP 22488, 1, 169.2 mm SL; MCP 44240, 6, 163.8–190.7 mm SL; MCP 50059, 83.6–176.4 mm SL; MNRJ 762, 3, 130.1–161.2 mm SL; MNRJ 35534, 15, 79.9–166.1 mm SL, 3 cs; MNRJ 35535, 3, 176.3–161.3 mm SL; MNRJ 35536, 2, 76.3–176.8 mm SL; MNRJ 35537, 2, 99.7–179.9 mm SL; MNRJ 39040, 8, 52.1–73.7 mm SL; MNRJ 39249, 1, 66.6 mm SL; MNRJ 39270, 6, 34.4–66.8 mm SL; MPEG 3072, 2, 71,7–146.2 mm SL; MPEG 9008, 4, 147–182.3 mm SL; MPEG 13290, 5, 157.9–180.3 mm SL; MPEG 17077, 1, 50.8 mm SL; MPEG 19827, 1, 182.2 mm SL; MPEG 19945, 1, 123.8 mm SL; MPEG 23942, 2, 139–175.4 mm SL; MPEG 23726, 2, 166.4–172.5 mm SL; MPEG 24470, 1, 129.2 mm SL; MPEG 24471, 2, 166.3–74 mm SL; MPEG 30598, 5, 118.3–151.1 mm SL; MPEG 30931, 1, 104.2 mm SL; MPEG 30936, 1, 109.7 mm SL; MZUSP 23416, 5, 35.9–139.2 mm SL; MZUSP 27717, 1, 115.8 mm SL; MZUSP 121244, 1, 207.0 mm SL; UFRGS 21710, 1, 80.5 mm SL; Peru: ANSP 191818, 2, 172.7–179.6 mm SL; ANSP 199910, 1, 146.1 mm SL; Farlowella azpelicuetae: Argentina: MZUSP 123935, paratype, 80.8 mm SL; MZUSP 123936, 2, paratypes, 79.8–165.9 mm SL; Farlowella gianetti: Brazil: MZUSP 95564, holotype, 114.4 mm SL; MZUSP 97022, paratypes, 94.1–118.6 mm SL; Farlowella cf. hahni: Brazil: MZUEL 9037, 5, 56.6–131 mm SL; MZUEL 9669, 1, 47.2 mm SL; NUP 374, 6, 78.1–161.7 mm SL; NUP 818, 5, 127.6–140 mm SL; NUP 819, 10, 89.3–156.2 mm SL; NUP 1450, 1, 111.7 mm SL; NUP 1496, 5, 95.7–177.8 mm SL; NUP 2849, 1, 128.4 mm SL; NUP 4029, 2, 151.1–162.2 mm SL; NUP 4525, 1, 130.7 mm SL; NUP 4728, 5, 129.4–148 mm SL; NUP 7867, 2, 134.7–140.3 mm SL; NUP 11443, 1, 109.5 mm SL; NUP 13303, 2, 103.2–129.7 mm SL; NUP 14747, 1, 125.6 mm SL; NUP 16978, 2, 133.8–149.8 mm SL; Farlowella hasemani: Brazil: INPA 3912, 190.8 mm SL; Farlowella henriquei: Brazil: INPA 3012, 2, 68.8–111 mm SL; INPA 3030, 1, 170.3 mm SL; INPA 3911, 147.9–153.1 mm SL; INPA 3913, 1, 180.7; INPA 34545, 3, 83.6–160.5 mm SL; MZUSP 2159, holotype, 165.7 mm SL; Farlowella isbruckeri: Brazil: MZUSP 27704, paratype, 134.8 mm SL; Farlowella jauruensis: Brazil: MZUSP 59457, 2, 58.3–57.3 mm SL; MZUSP 58485, 1, 77.2 mm SL; MZUSP 115560, 1, 81.4 mm SL; Farlowella knerii: Ecuador: ANSP 130435, 2, 21.4–73.3 mm SL; ANSP 130436, 1, 123.3 mm SL; Farlowella latisoma: Brazil: MNRJ 761, holotype, 179.3 mm SL, synonymy of Farlowella schreitmuelleri; Farlowella mariaelenae: Venezuela: ROM 94123, 2, 67.2–81.8 mm SL; Farlowella mitoupibo: Colombia: MPUJ 8481, holotype, 203.7 mm SL; MPUJ 8479, 1, paratype, 112.6 mm SL; MPUJ 8480, paratype, 5, 65.7–170 mm SL; MPUJ 8482, paratype, 109.4 mm SL; MPUJ 8483, paratype, 1, 163.1 mm SL; MPUJ 8484, paratype, 1, 112.5 mm SL; Farlowella myriodon: Peru: MZUSP 15328, holotype, 154 mm SL; MZUSP 15332, paratype, 134.2 mm SL; MZUSP 15342, paratype, 92.6 mm SL; Farlowella nattereri: Brazil: LBP 10568, 3, 80.7–92.4 mm SL; LBP 18192, 6, 47.5–117.5 mm SL; LBP 18526, 1, 189.9 mm SL; LBP 18580, 3, 102.9–164.5 mm SL; LBP 26628, 7, 185.0–208.6 mm SL; MNRJ 3732, 2, 166.9–168.2 mm SL; MNRJ 37080, 1, 135.7 mm SL; UFRO–ICT 6731, 2, 96.4–104.6 mm SL; UFRGS 26186, 1, 147.7 mm SL; Colombia: ROM 107219, 3, 90.3–213 mm SL; Peru: LBP 22594, 1, 132.3 mm SL; ROM 64063, 6, 42.9–129.8 mm SL; Farlowella aff. nattereri: Brazil: INPA 1637, 1, 117.8 mm SL; INPA 1963, 2, 78.7–146.1 mm SL; INPA 2017, 1, 87.5 mm SL; INPA 2808, 1, 171.8 mm SL; INPA 3916, 1, 95 mm SL; INPA 4839, 1, 184.5 mm SL; INPA 12945, 1, 162.5 mm SL; INPA 16763, 1, 52 mm SL; INPA 43891, 1, 199.1 mm SL; Guyana: INPA 58225, 2, 135.6–52.7 mm SL; ROM 97162, 1, 112.3 mm SL; Farlowella oliveirae Miranda Ribeiro, 1939: MNRJ 757, holotype, 111.8 mm SL, synonymy of Farlowella amazonum; Farlowella aff. oxyrryncha: Brazil: INPA 12940, 6, 61–155.2 mm SL; INPA 12941, 1, 60.5 mm SL; INPA 29869, 5, 29.9–105.1 mm SL; INPA 31038, 1, 100.3 mm SL; MZUEL 6713, 1, 103 mm SL; Farlowella cf. oxyrryncha: Brazil: INPA 1645,1, 86.4 mm SL; INPA 8159, 3, 61.9–151.6 mm SL; INPA 10371, 21, 72.33–188 mm SL; INPA 12964, 1, 56.3 mm SL; INPA 14001, 1, 159.2; INPA 20796, 1, 134.4 mm SL; INPA 27505, 21, 23.9–129.3 mm SL; INPA 37694, 1, 75 mm SL; INPA 53229, 1, 199.8 mm SL; INPA 54977, 1, 110 mm SL; INPA 58662, 1, 170.5 mm SL; MCP 32735, 1, 83 mm SL; MCP 36623, 7, 51.6–112.7 mm SL; MCP 46138, 1, 103 mm SL; MPEG 13083, 3, 116.4–127 mm SL; MPEG 28662, 5, 73.7–178.5 mm SL; MPEG 30901, 1, 103.7 mm SL; UFRGS 12165, 4, 105,5–97.7 mm SL; UFRGS 12325, 5, 49.8–133.6 mm SL; UFRGS 21842, 1, 100.3 mm SL; MNRJ 23380, 1, 115.4 mm SL; MZUSP 22919, 6, 47.7–101.8 mm SL; MZUSP 96753, 8, 55.9–101 mm SL; MZUSP 125342, 10, 69.2–195 mm SL; Farlowella paraguayensis Retzer & Page, 1997: Brazil: INPA 567, 5, 72.3–122.1 mm SL; INPA 2829, 4, 65.1–135 mm SL; INPA 2830, 6, 70.5–153.2; INPA 3919, 12, 56.5–88.7 mm SL; INPA 12999, 4, 59.8–110.7 mm SL; MNRJ 760, 1, 162.0 mm SL; MNRJ 46680, 2, 117.8–118.3 mm SL; MZUSP 47243, 8, paratypes, 122.5–134.4 mm SL; NUP 15010, 8, 51.7–95.8 mm SL; NUP 21531, 5, 56.3–101 mm SL; ZUFMS 1292, 2, 134.6–143.3 mm SL; ZUFMS 1426, 3, 112.9–122.3 mm SL; ZUFMS 4373, 3, 113.7–128.4 mm SL; ZUFMS 5950, 4, 74.2–122.9 mm SL; Farlowella pleurotaenia Miranda Ribeiro, 1939: Brazil: MNRJ 758, holotype, 99.6 mm SL, synonymy of Farlowella amazonum; Farlowella rugosa Boeseman, 1971: Brazil: IEPA 3886, 1, 187.2 mm SL; IEPA 3916, 1, 113.6 mm SL; Guyana: ROM 64797, 1, 143.5 mm SL; ROM 85790, 3, 73.9–87.4 mm SL; ROM 85916, 1, 73.7 mm SL; ROM 85922, 2, 81.9–143.1 mm SL; ROM 86116, 2, 63.5–65 mm SL; Suriname: ROM 98122, 1, 90.64 mm SL; Farlowella schreitmuelleri: Brazil: IEPA 2708, 1, 59 mm SL; IEPA 4644, 1, 66.9 mm SL; IEPA 4708, 1, 63.1 mm SL, IEPA 4724, 2, 80.1–121.8 mm SL; IEPA 4727, 6, 63.3–120.6 mm SL; INPA 3917, 1, 82.8 mm SL; INPA 3918, 1, 76.2 mm SL; INPA 6777, 9, 63.1–104.7 mm SL; INPA 6978, 3, 67.6–111.3 mm SL; INPA 7069, 1, 76 mm SL; INPA 8209, 1, 75.8 mm SL; INPA 24914, 11, 78.8–125.4 mm SL; INPA 29109, 2, 55.3–66.5 mm SL; INPA 44877, 5, 66.2–111 mm SL; INPA 44493, 1, 110.1 mm SL; INPA 44662, 1, 71.4 mm SL; INPA 45127, 2, 99.4–113.3 mm SL; INPA 45891, 13, 59.5–115.4 mm SL; INPA 46005, 1, 98.6 mm SL; INPA 46027, 1, 119.7 mm SL; MZUSP 101583, 2, 91.6–132 mm SL; MZUSP 101828, 1, 93.1 mm SL; UNT 488, 3, 106.5–140.7 mm SL; UNT 488, 3, 106.5–140.7 mm SL; Farlowella smithi Fowler, 1913: Brazil: UFRGS 25175, 3, 60.9–71.8 mm SL; UFRO–ICT 507, 3, 64.8–89.9 mm SL; UFRO–ICT 24122, 3, 70.3–88.9 mm SL; MZUSP 73593, 14, 56.9–85.8 mm SL; Farlowella vittata Myers, 1942: Colombia: LBP 18722, 2, 51.9–130.6 mm SL; MPUJ 8349, 8, 37.4–124.4 mm SL; MPUJ 8353, 2, 54.3–75.1 mm SL; MPUJ 8357, 7, 78.9–128.3 mm SL; Venezuela: LBP 2307, 1, 87.4 mm SL; LBP 9950, 2, 51.6–123.4 mm SL; ROM 88294, 6, 90.4–77.5 mm SL; ROM 94407, 3, 62–136.3 mm SL.
ACKNOWLEDGEMENTSWe are grateful to Mariangeles Arce and Mark Sabaj (ANSP); Cecile Gama (IEPA); Lucia Rapp Py-Daniel, Renildo Oliveira and Vitoria Pereira (INPA); Claudio Oliveira (LBP); Isaac Cabral and Leandro Sousa (LIA); Carlos Lucena (MCP); Alberto Akama and Angelo Dourado (MPEG); Alejandra Rodríguez, Tiago Carvalho and Saul Prada (MPUJ); Alessio Datovo, Guilherme Dutra, Mario de Pinna and Michel Gianeti (MZUSP); Carla Pavanelli and Marli Campos (NUPELIA); Marg Zur and Nathan Lujan (ROM); Fernando Jerep and José Birindelli (UEL); Juliana Wingert and Luiz Malabarba (UFRGS); Aline Andriolo and Carolina Doria (UFRO); Carine Chamon, Everton Oliveira and Paulo Lucinda (UNT); Francisco Severo Neto and Thomaz Sinani (ZUFMS) for loan material and assistance during visits of the first author to collections under their care. Alejandro Londoño-Burbano (MNRJ) for comments and discussion about the Loricariinae and generous contributions to this manuscript. Roberto Reis (MCP), Jonathan Armbruster (AUM) and an anonymous reviewer provided useful comments that helped improve the manuscript. Lucas Garcia (MNRJ) for the drawing of Fig. 1. Igor Souto-Santos (MNRJ) for helping with photos for Figs. 2, 3 and 4. Guilherme Dutra (MZUSP) for the photograph of the type locality. MD is supported from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES/PROEX 88887.335793/2019–00). MRB and WBW are supported by grants from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, processes #311294/2021–9 and #307988/2021–0).
Manuela DopazoWolmar B. WosiackiMarcelo R. BrittoABOUT THE AUTHORS
- Abstract
- Resumo
- Text
- ACKNOWLEDGEMENTS
- REFERENCES
- ADDITIONAL NOTES
- Edited-by
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- History
Keywords:
Amazon; Armored catfish; Biodiversity; Loricariinae; Taxonomy
ResumoUma nova espécie de cascudo-graveto Farlowella é descrita de pequenos igarapés do baixo rio Tapajós, no Estado do Pará, norte do Brasil. A nova espécie é distinta de todas as suas congêneres por uma região gular nua (vs. região gular com placas) e de muitas congêneres pela presença de cinco fileiras de placas laterais na região anterior do corpo (vs. quatro). A nova espécie apresenta variação na série de placas abdominais e é feita uma discussão sobre a variação das placas abdominais dentro de Farlowella e comentários sobre caracteres sinapomórficos em Farlowellini.
Palavras-chave:
Amazônia; Biodiversidade; Cascudo; Loricariinae; Taxonomia
INTRODUCTIONThe genus FarlowellaEigenmann & Eigenmann, 1889 is a component of the freshwater fish fauna of the Neotropics. With 32 valid species, Farlowella is the second-most species-rich genus of Loricariinae, a sub-family comprised of 262 valid species in 31 genera (Delgadillo et al., 2021; Londoño-Burbano, Reis, 2021; Fricke et al., 2023). Farlowella representatives are widely distributed in the main cis-Andean South America river drainages and trans-Andean Maracaibo and Magdalena river basins (Terán et al., 2019). They are easily distinguished by having a pronounced rostrum, a thin, elongated, brown body with two longitudinal bands that extend from the tip of the rostrum to the caudal peduncle (Covain, Fisch-Muller, 2007), resembling dry twigs or sticks, which justifies the popular name stick catfishes.
The first taxonomic study was the description of the genus Acestra by Kner, (1853), with the first species described: Acestra acus and A. oxyrryncha, but without designating the type species of the genus, until A. acus was determined by Bleeker, (1862). However, Acestra was already occupied in Hemiptera (Dallas, 1852) and the name Farlowella was then replaced by Eigenmann, Eigenmann, (1889). From the end of the 19th century, several species were described, totaling 37 names that remained for almost a century, when Retzer, Page (1996) revised the genus based on characters of external morphology. This was the last revision of its species, as well as the first exclusive hypothesis of the phylogenetic relationships of the genus. In that study, the authors performed a phylogenetic analysis with morphological data including only one external group, Aposturisoma myriodon Isbrücker, Britski, Nijssen & Ortega, 1983 (= Farlowella myriodon), that was used to root the tree; the monophyly of the genus, and species relationships were not actually tested. The authors also proposed six species groups and six species were considered as incertae sedis.
Recently, Londoño-Burbano, Reis (2021), based on combined molecular and morphological phylogenetic analysis, formally recognized Aposturisoma myriodon as a member of Farlowella to assign the monophyly of the genus. Although A. myriodon is phenotypically different from Farlowella, this configuration had already been recovered by Covain et al., (2016). Based on the review of Farlowella material deposited in different collections and on the examination of material collected in the river near the confluence with rio Tapajós, in its lower portion, we identified a new species of Farlowella, which is described herein.
MATERIAL AND METHODSMeasurements were taken point to point with digital calipers. Measurements are expressed as percents of the standard length (SL), except subunits of head, which are expressed as percents of the head length (HL). Measurements follow Boeseman, (1971), except measurement of distance from pectoral-fin origin to pelvic-fin origin that follow Retzer, Page (1996), plus minimum width of snout (minimum width at the tip of snout) (Fig. 1A), distance between cleithral processes (between the humeral processes of the cleithrum) (Fig. 1B) and maximum width of snout (maximum width in transverse line from the posterior edge of the ventral plate before mouth) (Fig. 1C). Counts and nomenclature of lateral plate series follow Ballen et al., (2016a). Osteological nomenclature follows Paixão, Toledo-Piza, (2009), except for parieto-supraoccipital instead of supraoccipital (Arratia, Gayet, 1995), pterotic-extraescapular instead of pterotic-supracleithrum (Slobodian, Pastana, 2018). Vertebral counts include only free centra, with the compound caudal centrum (preural 1+ ural 1) counted as a single element. Cleared and stained (cs) specimens were prepared according to the methods of Taylor, Van Dyke, (1985). Numbers in parentheses following meristic counts correspond to number of specimens having that count, and those indicated by an asterisk (*) belong to the holotype. Map was generated in the QGIS 3.14.16 program. Institutional abbreviations follow Sabaj, (2022). The estimated Extent of Occurrence (EOO) and Area of Occupation (AOO) of the species was calculated using the web portal of the Geospatial Conservation Assessment Tool (GeoCAT: http://geocat.kew.org/) and the categories and criteria of conservation status of species followed IUCN (IUCN Standards and Petitions Committee, 2022).
FIGURE 1 |
Additional measures used in this study. A. Minimum width of snout; B. Distance between cleithral processes; and C. Maximum width of snout.
RESULTSFarlowella wuyjugu, new species
urn:lsid:zoobank.org:act:FA22FB00-B26F-45C0-A121-2BD8FB00B523
(Figs. 2–3; Tab. 1)
Holotype. MPEG 26178, 143.4 mm SL, Brazil, Pará State, Juruti municipality, lower rio Tapajós, rio Amazon basin, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça.
Paratypes. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. INPA 59894, 2, 124.8–128.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MNRJ 53691, 2, 127.3–130.9 mm SL, same locality as INPA 59894. MPEG 10062, 5, 112.0–121.6 mm SL, same locality as INPA 59894, 3 Mar 2006, L. F. A. Montag. MPEG 12865, 5, 90.9–123.2 mm SL, same locality as INPA 59894, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 15900, 12, 2 cs, 97.6–136.5 mm SL, same locality as INPA 59894, 8 Sep 2002, W. B. Wosiacki. MPEG 10857, 5, 111.7–128.2 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Aug 2006, A. Hercos. MPEG 32191, 4, 94.3–133.9 mm SL, same locality as MPEG 10857, 14 Sep 2014, M. B. Mendonça. MPEG 12684, 5, 1 cs, 122.8–144.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°50’13.8”W, 14 Dec 2006, L. F. A. Montag.
Non-types. All from Brazil, Pará State, Juruti municipality, rio Arapiuns basin, lower rio Tapajós, rio Amazon basin. MPEG 10055, 4, 102.9–124.3 mm SL, MPEG 10062, 13, 70.0–109.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 3 Mar 2006, L. F. A. Montag. MPEG 10851, 1, 119.2 mm SL, MPEG 10852, 3, 79.5–116.1 mm SL, MPEG 10853, 1, 121.9 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10855, 4, 46.7–88.7 mm SL, MPEG 10856, 7, 54.2–108.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10857, 11, 65.1–145.8 mm SL, MPEG 10858, 2, 106.2–112.8 mm SL, MPEG 10859, 4, 64.4–128.3 mm SL, MPEG 10861, 1, 113.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10860, 1, 128.6 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 10862, 3, 49.6–54.6 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, A. Hercos. MPEG 10956, 1, 26.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of rio Branco, 02°36’44.5”S 56°11’35.5”W, 17 Aug 2006, A. Hercos. MPEG 12491, 4, 18.6–45.8 mm SL, igarapé Mutum, 02°36’44.8”S 56°11’37.3”W, 9 Sep 2002, W. B. Wosiacki. MPEG 12865, 4, 69.8–93.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02º36’44.5”S 56º11’37.3”W, 11 Dec 2006, L. F. A. Montag & A. Hercos. MPEG 13040, 2, 35.7–38.4 mm SL, MPEG 13043, 2, 20.6–30 mm SL, MPEG 13050, 2, 11.0–118.4 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 19 Aug 2006, L. F. A. Montag. MPEG 13041, 1, 56.3 mm SL, MPEG 13044, 5, 56.8–93.2 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 12 Dec 2006, L. F. A. Montag. MPEG 13042, 3, 48.1–45.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13045, 1, 92.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 14 Dec 2006, L. F. A. Montag. MPEG 13046, 1, 101.7 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 Dec 2006, L. F. A. Montag. MPEG 13048, 5, 50.2–80.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 Dec 2006, L. F. A. Montag. MPEG 13731, 2, 63.9–69.4 mm SL, MPEG 14143, 7, 61.9–136.5 mm SL, igarapé São Francisco, 02°34’50.7”S 55°54’13.8”W, 15 May 2007, A. Hercos. MPEG 14271, 1, 42.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 27 Nov 2007, A. Hercos. MPEG 14711, 13, 46.2–126.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’35.5”W, 11 May 2007, A. Hercos. MPEG 15900, 8, 56.6–95.8 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’44.5”S 56°11’37.3”W, 8 Sep 2002, W. B. Wosiacki. MPEG 16955, 1, 120.7 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’33.2”S 56°11’33.4”W, 19 Feb 2008, W. B. Wosiacki. MPEG 26172, 13, 71.8–129.8 mm SL, MPEG 26173, 4, 61.5–94.5 mm SL, MPEG 26333, 1, 86.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 28 Nov 2012, M. B. Mendonça. MPEG 26179,19, 43.5–156.4 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 27 Nov 2012, M. B. Mendonça. MPEG 29996, 2, 112.7–117.4 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 6 Dec 2013, M. B. Mendonça. MPEG 26997, 9, 100.5–129.9 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 7 Dec 2013, M. B. Mendonça. MPEG 26998, 1, 88.9 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 11 Dec 2013, M. B. Mendonça. MPEG 26999, 5, 51.9–138.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 12 Dec 2012, M. B. Mendonça. MPEG 32191, 4, 93.7–136.6 mm SL, MPEG 32192, 2, 55.6–115.1 mm SL, igarapé São Francisco, 02°34’52”S 55°54’10.8”W, 19 Sep 2014, M. B. Mendonça. MPEG 32193, 15, 32.9–124.2 mm SL, MPEG 32194, 14, 61.4–127.3 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 22 Sep 2014, M. B. Mendonça. MPEG 32195, 1, 135.1 mm SL, igarapé Rio Branco, 02°20’58.6”S 56°01’26.4”W, 18 Sep 2014, M. B. Mendonça. MPEG 32507, 72.4–113.1 mm S, MPEG 32508, 11, 49.0–116.5 mm SL, igarapé Mutum, affluent of rio Aruã, tributary of Rio Branco, 02°36’45.8”S 56°11’36.8”W, 20 Mar 2015, M. B. Mendonça.
FIGURE 2 |
Dorsal, lateral and ventral view of Farlowella wuyjugu, holotype, 143.4 mm SL, MPEG 26178, Brazil, Pará State, Juruti municipality, igarapé Rio Branco, lower rio Tapajós, rio Amazon basin.
Diagnosis.Farlowella wuyjugu can be diagnosed from its congeners by lack of plates in gular region (vs. gular plates present) (Fig. 3). The new species can be distinguished from its congeners, except Farlowella altocorpus Retzer, 2006, F. azpelicuetae Terán, Ballen, Alonso, Aguilera & Mirande, 2019, F. gianetii Ballen, Pastana & Peixoto, 2016, F. gracilis Regan, 1904, F. guarani Delgadillo, Maldonado & Carvajal-Vallejos, 2021, F. hasemani Eigenmann & Vance, 1917, F. isbrueckeri Retzer & Page, 1997, F. jauruensis Eigenmann & Vance, 1917, F. myriodon, F. nattereri Steindachner, 1910, and F. odontotumulusRetzer & Page, 1997, by having five lateral series of plate rows on anterior region of body (vs. four). Additionally, F. wuyjugu differs from F. altocorpus and F. azpelicuatae by having a smaller body width at dorsal origin (4.3–5.5 vs. 6.4–8.1% SL); from F. gianetti by number of caudal-fin rays (i,11,i or i,12,i vs. i,10,i); from F. gracilis by having head triangular in dorsal view (vs. head square); from F. guarani by interorbital width (12.0–16.0 vs. 28.6–44% HL) and eye diameter (3.6–5.8 vs. 6.6–13.3% HL); from F. hasemani by all fin rays uniformly pigmented (vs. fin rays not pigmented); from F. isbruckeri and F. odontotumulus by having the ventromedian row of anterior plates keeled (vs. ventromedian row of anterior plates unkeeled); from F. jauruensis by having five branched pelvic-fin rays (vs. four branched pelvic-fin rays); from F. myriodon by having dark brown lateral stripe on each side of snout (vs. absence of such stripe, snout completely dark); and from F. nattereri by having a short pectoral fin, not reaching the pelvic-fin base (vs. long pectoral fin, reaching the pelvic-fin base).
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TABLE 1 |
Morphometrics of Farlowella wuyjugu, new species. Values as percents of standard length (SL) and head length (HL) for holotype and 38 paratypes. n = number of specimens, SD = Standard deviation.
Description. Dorsal, lateral, and ventral views of holotype in Fig. 2. Morphometric and meristic data for holotype and paratypes summarized in Tab. 1. Body slender and very elongated, completely covered by dermal plates, except in gular portion. Head triangular and elongate in dorsal and ventral views. Rostrum slender and flat in ventral view. Orbit circular, dorsolaterally placed, visible in dorsal view and not visible in ventral view. Preorbital ridge present. Mouth ventral. Dorsal profile of head concave from snout tip to anterior margin of nares, relatively straight to convex from point to posterior margin of nares to posterior margin of parieto-supraoccipital and slightly concave to dorsal-fin origin. Posterior profile of margin of dorsal-fin origin slightly concave and straight profile to end of caudal peduncle. Ventral profile slightly straight from tip of snout to anal-fin origin, slightly concave in anal-fin base and straight profile to end of caudal peduncle.
Mouth ovoid, lower lip longer than upper lip; wide oval papillae on upper lip and round papillae on lower lip, decreasing in size from oral aperture to lip margin; lip margin papillose. Bicuspid slender teeth, each premaxilla with 22(2), 23*(1), 29(1), 31(1), 33(1), 36(1), 37(3), 39(1), 40(2), 41(1), 42(3), 43(2), 44(1), 46(3), 47(4), 48(4), 49(4), 51(2), 53(1) or 55(1) teeth and each dentary with 18*(3), 22(1), 23(1), 26(2), 28(1), 29(2), 30(2), 32(3), 33(3), 34(1), 35(4), 36(3), 37(1), 38(4), 39(2), 40(2), 41(1), 42(1) or 43(2) teeth; premaxilla larger than dentary. Two maxillary barbels small and projecting slightly from mouth margin.
Five lateral plate rows on body, with 31(6), 32*(30) or 33(3) dorsal plates; 6(1), 7*(5), 8(23) or 9(10) dorsomedian plates; 7(1), 8*(5), 9(20) or 10(13) median plates; 14*(7), 15(27) or 16(5) ventromedian plates; 35(3), 36(7), 37*(15), 38(9), 39(3) or 40(2) ventral plates; 5(14), 6*(18), 7(6) or 8(1) dorsomedian+median plates; 18(12), 19(20) or 20*(7) coalescent plates; 8*(39) predorsal plates; 23(6), 24*(30) or 25(3) postdorsal plates; 20(2), 21(14), 22*(21), 23(1) or 24(1) postanal plates; 2 plates at the base of caudal fin and one preanal plate. Abdomen covered with two lateral rows with 6(6), 7*(19), 8(11), 9(2), 11(1) lateral abdominal plates (left) and 6(10), 7*(14), 8(8) or 9(7) lateral abdominal plates (right), and one midabdominal incomplete (23)* row or when complete (16) row with 2(1), 3(2), 4*(2), 5(1), 6(5), 7(7), 8(7), 9(3), 10(3), 11(2), 12(3), 13(2) or 16(1) midabdominal plates.
Lateral line complete; reaching up to last caudal peduncle coalesced plate. Preopercular canal passing through infraorbital six with two pores. Terminal exit of parietal branch in frontal bone curved. Canal-bearing cheek plate in ventral position. Nasal slightly curved in anterior portion with pore opening laterally.
Pectoral-fin rays i,6*(39); posterior margin slightly concave; unbranched ray longest. Dorsal-fin rays i,6*(39); posterior margin straight to slightly concave; three* or four plates along its base; unbranched ray longest. Pelvic-fin rays i,5*(39); posterior margin straight; unbranched ray longest. Anal-fin rays i,5*(39); posterior margin straight to slightly concave; unbranched ray longest; three* or four plates along its base. Caudal-fin rays i,11,i(2) or i,12,i*(37); posterior margin deeply concave; dorsal and ventral lobes similar in size; filaments on upper and lower unbranched rays. All fin rays with odontodes; more developed odontodes on unbranched first ray.
Mesethmoid long; lateral expansion of anterior portion absent; mesethmoid ventral posterior process present. Nasal rectangular irregular bone curved laterally. Frontal wide, occluded from dorsal border of orbit. Orbit anteriorly delimited by dermal plate, dorsally by frontal bone, dorsolaterally by sphenotic, and ventrally by infraorbital series. Sphenotic quadrate in shape, contacting frontal bone anterolaterally, parieto-supraoccipital dorsally, infraorbital six ventrally, and pterotic-extrascapular posteriorly. Pterotic-extrascapular with large perforations. Parieto-supraoccipital wide and oval, contacting first predorsal plate posteriorly. Anterior contact of hyomandibula with metapterygoid and quadrate, and ventral with preopercle. Symphyseal cartilage between quadrate and hyomandibula. Anterior margin of quadrate articulation with anguloarticular. Dentary almost twice the size of anguloarticular. Autopalatine irregular, rod-like shape. Anterior margin of autopalatine articulation with maxilla and posterior contact posteriorly with vomer and metapterygoid. Preopercle long and partially exposed; anterior process reaching at least half of quadrate length. Suspensorium rectangular in overall shape. Three branchiostegal rays. Hypohyal anterior border straight, without anterior projection. Urohyal triangular and posterior margin rounded, with medial foramen. Anterohyal and posterohyal partially separated by cartilage. Anterior margin of anterohyal greatly expanded. Basibranchial 2, 3 and 4 present; basibranchial 2 and 3 elongated; basibranchial 2 equal to basibranchial 3; basibranchial 2 and 3 ossified and basibranchial 4 cartilaginous. Two hypobranchials; hypobranchial 1 ossified and hypobranchial 2 cartilaginous. Four epibranchials with similar size. Five ceratobranchials; ceratobranchial 1 with accessory flange; ceratobranchial 5 triangular; ceratobranchial teeth restricted to mesial area of plate. Upper pharyngeal plate club-shaped, completely covered with fine teeth. Vertebral count 39(1) and 40(1); five thin pleural ribs directly attached to centra 8, 9, 10, 11 and 12(1) and four thin pleural ribs directly attached to centra 9, 10, 11 and 12(1); parapophysis of complex vertebra well developed (two specimens).
FIGURE 3 |
Gular region and variation of abdominal plates in specimens, ventral view of Farlowella wuyjugu. A. MPEG 26178, 143.4 mm SL; B. INPA 59894, 128.9 mm SL; C. MPEG 12684, 125 mm SL.
Coloration in alcohol. Ground color of dorsum and head pale or dark brown. Light brown color with diffuse and scattered dark brown spots on predorsal portion, from tip of parieto-supraoccipital and extending to all plates. Five to six rounded spots between the second and third infraorbital, extending to opercle. One dark brown lateral stripe on each side, that runs from snout to caudal peduncle. Ventral portion of head brown; yellow between lower lip and anterior portion of anal fin. Dorsal profile in posterior portion of anal fin light brown with diffuse and scattered dark brown spots along the plates, same to dorsal portion, more delimited in some individuals. Upper lip with scattered chromatophores. Pectoral, dorsal, pelvic, and anal fin rays with hyaline membranes and pigmented brown rays, sometimes forming dark bands. First rays markedly dark. Caudal fin almost completely dark brown, membranes and rays pigmented, in some individuals with area of hyaline membrane (Fig. 4).
FIGURE 4 |
Caudal fin coloration of Farlowella wuyjugu. MPEG 31191, 119.9 mm SL.
Geographical distribution.Farlowella wuyjugu is known only from small, forest creeks near Juruti, Pará State, tributaries of rio Arapiuns, rio Tapajós in its lower portion, rio Amazon basin, Brazil (Fig. 5).
FIGURE 5 |
Geographic distribution of Farlowella wuyjugu in lower rio Tapajós. Star = holotype; circles = paratypes localities.
Etymology. The specific epithet refers to the combination of the words Wuy jugu, which is the self-denomination of indigenous people known in Brazil as Munduruku. This ethnic group is part of the Tupi trunk and they are located in different regions and territories in the states of Pará, Amazonas, and Mato Grosso. In the region of the lower Tapajós River, in recent years some communities in the process of their ethnic identity have recognized themselves as Munduruku (Ramos, 2022). A noun in apposittion.
Conservation status.Farlowella wuyjugu is known from four collection stations [igarapé Rio Branco (Fig. 6), igarapé Mutum, and igarapé São Francisco] in Juruti municipality, Pará State, Brazil. Using the GeoCAT we calculate the extent of occurrence (EOO) of the species in 4,921 km2, suggesting a threatened category of Endangered (EN). Farlowella wuyjugu is sampled in few localities in the Juruti municipality, impacted by a large bauxite extraction project, deteriorating their habitats. Following the recommendations by the IUCN (IUCN Standards and Petitions Committee, 2022), F. wuyjugu should be categorized as Nearly Threatened (NT), following criterions B2:EN (EOO < 5,000 km2), b(iii) (decline of quality of habitat by bauxite extraction).
FIGURE 6 |
Igarapé Rio Branco, type-locality of Farlowella wuyjugu.
Variation of abdominal plates within Farlowellawuyjugu. Abdominal plates are usually termed as lateral abdominal plates, which are transversely elongated plates between the pectoral-fin axilla and the pelvic-fin insertion, and midabdominal plates, which cover the abdomen between the lateral ones (Londoño-Burbano, Reis, 2021). The midabdominal plates, in Farlowella, can be absent or present and when present can be incomplete or complete. Ballen et al., (2016b) described Falowella mitoupiboBallen, Urbano-Bonilla & Zamudio, 2016 and proposed as diagnostic for the species an incomplete median disjunct row of abdominal plates, divided at the center by plates belonging to the lateral rows of abdominal plates (vs. two or three complete rows of abdominal plates or an incomplete median row of one or two plates anteriorly that never reach to the level of the prepelvic plate). Although the authors proposed this character as a diagnosis for the species, in recent examinations of the type material of F. mitoupibo, it was possible to observe two completes rows of abdominal plates in one specimen (M. Dopazo, pers. obs.). Farlowella wuyjugu have midabdominal plates and can be an incomplete or complete midabdominal series (Fig. 3). An incomplete midabdominal series can be a disjunct row as described for F. mitoupibo or an incomplete median row of plates anteriorly that do not reach to the level of the prepelvic plate (Figs. 3A, B). Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species group of Farlowella: two rows (F. acus (Kner, 1853) group and F. amazonumGünther, 1864 group) and three rows (F. curtirostra Myers, 1942 group, F. mariaelene Martín Salazar, 1964 group, F. nattereri group, F. knerii (Steindachner, 1882) group and unassigned species group). Although Retzer, Page (1996) proposed the number of rows of abdominal plates as a diagnostic character to differentiate species groups of Farlowella, both states were found in F. wuyjugu and F. mitoupibo, rendering that character not be useful to differentiate groups because they are variable within Farlowella species. A phylogenetic analysis of the genus (including the species described here) is being carried out and aims to test if these characters (proposed by Retzer, Page, 1996) are in fact phylogenetically informative.
DISCUSSIONLondoño-Burbano, Reis (2021) recovered the tribe Farlowellini Fowler, 1958 including five genera, Lamontichthys Miranda Ribeiro, 1939, Pterosturisoma Isbrücker & Nijssen, 1978, Sturisoma Swainson, 1838, Sturisomatichthys Isbrücker & Nijssen, 1979 and Farlowella Eigenmann & Eigenmann, 1889. The authors defined two exclusive synapomorphies for the tribe: (1) nuchal plate articulated to lateral plates (char 175) and (2) the presence of gular plates (char 179). According to Londoño-Burbano, Reis (2021), gular plates are large, polygonal dermal plates covering the ventral surface of the head behind the lower lip. Character 175 was observed in F. wuyjugu, however, character 179 is not applicable to the new species because of the lack of gular plates. Almost twenty years after the publication of the study by Retzer, Page (1996). Farlowella was proposed as a monophyletic group by Londoño-Burbano, Reis (2021) with 11 morphological and 38 molecular synapomorphies. Of the eleven morphological synapomorphies, four were considered exclusive for the genus: (1) number of branchiostegal rays fewer than four (char 109); (2) straight and upright lamina on neural spine on the sixth vertebra for articulation with ventral surface of parieto-supraoccipital (char 114); (3) absence of pleural rib associated to the seventh vertebra (char 117); (4) short anteriormost paraneural spines (char 129). These character states were all observed in F. wuyjugu supporting the species as a member of the genus. Despite the high number of morphological characters and the number of terminals used in the analysis by the authors, there are many high homoplastic characters and not useful for a diagnosis at the species level.
Other Farlowella species are also identified for the rio Tapajós basin (F. gr. amazonum, F. cf. oxyrryncha, F. schreitmuelleri Arnold, 1936, and F. sp.; M. Dopazo, pers. obs.). Species with type locality in or near the region are F. amazonum (Santarém, Pará State), F. gladiolusGünther, 1864 (rio Cupari, rio Tapajós basin, Amazon River drainage, Pará State), and F. schreitmuelleri (lower Amazon River basin, Santarém, Pará State), but they differ from F. wuyjugu mainly by the number of lateral series of plate rows on anterior region of body (four vs. five). Farlowella amazonum and F. gladiolus were described in the same work by Günther, (1864). In the review of the genus by Retzer, Page (1996), F. gladiolus was placed in the synonymy with F. amazonum, however, Covain et al., (2016) recognized the former as a valid species. There are several taxonomic issues regarding the validity of Farlowella species and their delimitation. These questions are being addressed in an ongoing taxonomic review (by MD and MRB) of the genus. Our description of F. wuyjugu contributes to the knowledge of the rio Arapiuns and to the understanding of the ichthyofauna of the rio Tapajós basin.
Comparative material examined.Farlowella acus: Colombia: MPUJ 2834, 1, 183.6 mm SL; MPUJ 2842, 1, 133.3 mm SL; MPUJ 2955, 1, 50.1 mm SL: MPUJ 7320,1 124.1 mm SL; MPUJ 9287, 1, 122.5 mm SL; MPUJ 10915, 1, 116.9 mm SL; MPUJ 11158, 1, 130.4 mm SL; MPUJ 13270, 1, 38.6 mm SL: MPUJ 16876, 1, 76 mm SL; Venezuela: ANSP 130038, 20, 90.6–149.7 mm SL; MZUSP 147, 2, 108.4–123.8 mm SL; Farlowella cf. altocorpus: Brazil: INPA 3034, 49, 64.2–155.6 mm SL; INPA 3035, 16, 58–148.6 mm SL; Farlowella amazonum: Brazil: LIA 7233, 1, 84.7 mm SL; LIA 7235, 64.8–198.5 mm SL; LIA 7236, 4, 69.2–92,5 mm SL; LBP 4344, 1, 82.9 mm SL; LBP 10860, 3, 111.0–144.7 mm SL; LBP 11118, 1, 132.2 mm SL; LBP 12117, 5, 47.4–147.2 mm SL; LBP 15179, 1, 82.9 mm SL; LBP 17994, 3, 70.7–121.81 mm SL; LBP 20432, 1, 110.1 mm SL; LBP 20964, 2, 67.5–113.1 mm SL; LBP 21208, 4, 69.5–121.7 mm SL; LBP 21230, 1, 142.1 mm SL; LBP 22348, 13, 54.9–203.6 mm SL; LBP 22488, 1, 169.2 mm SL; MCP 44240, 6, 163.8–190.7 mm SL; MCP 50059, 83.6–176.4 mm SL; MNRJ 762, 3, 130.1–161.2 mm SL; MNRJ 35534, 15, 79.9–166.1 mm SL, 3 cs; MNRJ 35535, 3, 176.3–161.3 mm SL; MNRJ 35536, 2, 76.3–176.8 mm SL; MNRJ 35537, 2, 99.7–179.9 mm SL; MNRJ 39040, 8, 52.1–73.7 mm SL; MNRJ 39249, 1, 66.6 mm SL; MNRJ 39270, 6, 34.4–66.8 mm SL; MPEG 3072, 2, 71,7–146.2 mm SL; MPEG 9008, 4, 147–182.3 mm SL; MPEG 13290, 5, 157.9–180.3 mm SL; MPEG 17077, 1, 50.8 mm SL; MPEG 19827, 1, 182.2 mm SL; MPEG 19945, 1, 123.8 mm SL; MPEG 23942, 2, 139–175.4 mm SL; MPEG 23726, 2, 166.4–172.5 mm SL; MPEG 24470, 1, 129.2 mm SL; MPEG 24471, 2, 166.3–74 mm SL; MPEG 30598, 5, 118.3–151.1 mm SL; MPEG 30931, 1, 104.2 mm SL; MPEG 30936, 1, 109.7 mm SL; MZUSP 23416, 5, 35.9–139.2 mm SL; MZUSP 27717, 1, 115.8 mm SL; MZUSP 121244, 1, 207.0 mm SL; UFRGS 21710, 1, 80.5 mm SL; Peru: ANSP 191818, 2, 172.7–179.6 mm SL; ANSP 199910, 1, 146.1 mm SL; Farlowella azpelicuetae: Argentina: MZUSP 123935, paratype, 80.8 mm SL; MZUSP 123936, 2, paratypes, 79.8–165.9 mm SL; Farlowella gianetti: Brazil: MZUSP 95564, holotype, 114.4 mm SL; MZUSP 97022, paratypes, 94.1–118.6 mm SL; Farlowella cf. hahni: Brazil: MZUEL 9037, 5, 56.6–131 mm SL; MZUEL 9669, 1, 47.2 mm SL; NUP 374, 6, 78.1–161.7 mm SL; NUP 818, 5, 127.6–140 mm SL; NUP 819, 10, 89.3–156.2 mm SL; NUP 1450, 1, 111.7 mm SL; NUP 1496, 5, 95.7–177.8 mm SL; NUP 2849, 1, 128.4 mm SL; NUP 4029, 2, 151.1–162.2 mm SL; NUP 4525, 1, 130.7 mm SL; NUP 4728, 5, 129.4–148 mm SL; NUP 7867, 2, 134.7–140.3 mm SL; NUP 11443, 1, 109.5 mm SL; NUP 13303, 2, 103.2–129.7 mm SL; NUP 14747, 1, 125.6 mm SL; NUP 16978, 2, 133.8–149.8 mm SL; Farlowella hasemani: Brazil: INPA 3912, 190.8 mm SL; Farlowella henriquei: Brazil: INPA 3012, 2, 68.8–111 mm SL; INPA 3030, 1, 170.3 mm SL; INPA 3911, 147.9–153.1 mm SL; INPA 3913, 1, 180.7; INPA 34545, 3, 83.6–160.5 mm SL; MZUSP 2159, holotype, 165.7 mm SL; Farlowella isbruckeri: Brazil: MZUSP 27704, paratype, 134.8 mm SL; Farlowella jauruensis: Brazil: MZUSP 59457, 2, 58.3–57.3 mm SL; MZUSP 58485, 1, 77.2 mm SL; MZUSP 115560, 1, 81.4 mm SL; Farlowella knerii: Ecuador: ANSP 130435, 2, 21.4–73.3 mm SL; ANSP 130436, 1, 123.3 mm SL; Farlowella latisoma: Brazil: MNRJ 761, holotype, 179.3 mm SL, synonymy of Farlowella schreitmuelleri; Farlowella mariaelenae: Venezuela: ROM 94123, 2, 67.2–81.8 mm SL; Farlowella mitoupibo: Colombia: MPUJ 8481, holotype, 203.7 mm SL; MPUJ 8479, 1, paratype, 112.6 mm SL; MPUJ 8480, paratype, 5, 65.7–170 mm SL; MPUJ 8482, paratype, 109.4 mm SL; MPUJ 8483, paratype, 1, 163.1 mm SL; MPUJ 8484, paratype, 1, 112.5 mm SL; Farlowella myriodon: Peru: MZUSP 15328, holotype, 154 mm SL; MZUSP 15332, paratype, 134.2 mm SL; MZUSP 15342, paratype, 92.6 mm SL; Farlowella nattereri: Brazil: LBP 10568, 3, 80.7–92.4 mm SL; LBP 18192, 6, 47.5–117.5 mm SL; LBP 18526, 1, 189.9 mm SL; LBP 18580, 3, 102.9–164.5 mm SL; LBP 26628, 7, 185.0–208.6 mm SL; MNRJ 3732, 2, 166.9–168.2 mm SL; MNRJ 37080, 1, 135.7 mm SL; UFRO–ICT 6731, 2, 96.4–104.6 mm SL; UFRGS 26186, 1, 147.7 mm SL; Colombia: ROM 107219, 3, 90.3–213 mm SL; Peru: LBP 22594, 1, 132.3 mm SL; ROM 64063, 6, 42.9–129.8 mm SL; Farlowella aff. nattereri: Brazil: INPA 1637, 1, 117.8 mm SL; INPA 1963, 2, 78.7–146.1 mm SL; INPA 2017, 1, 87.5 mm SL; INPA 2808, 1, 171.8 mm SL; INPA 3916, 1, 95 mm SL; INPA 4839, 1, 184.5 mm SL; INPA 12945, 1, 162.5 mm SL; INPA 16763, 1, 52 mm SL; INPA 43891, 1, 199.1 mm SL; Guyana: INPA 58225, 2, 135.6–52.7 mm SL; ROM 97162, 1, 112.3 mm SL; Farlowella oliveirae Miranda Ribeiro, 1939: MNRJ 757, holotype, 111.8 mm SL, synonymy of Farlowella amazonum; Farlowella aff. oxyrryncha: Brazil: INPA 12940, 6, 61–155.2 mm SL; INPA 12941, 1, 60.5 mm SL; INPA 29869, 5, 29.9–105.1 mm SL; INPA 31038, 1, 100.3 mm SL; MZUEL 6713, 1, 103 mm SL; Farlowella cf. oxyrryncha: Brazil: INPA 1645,1, 86.4 mm SL; INPA 8159, 3, 61.9–151.6 mm SL; INPA 10371, 21, 72.33–188 mm SL; INPA 12964, 1, 56.3 mm SL; INPA 14001, 1, 159.2; INPA 20796, 1, 134.4 mm SL; INPA 27505, 21, 23.9–129.3 mm SL; INPA 37694, 1, 75 mm SL; INPA 53229, 1, 199.8 mm SL; INPA 54977, 1, 110 mm SL; INPA 58662, 1, 170.5 mm SL; MCP 32735, 1, 83 mm SL; MCP 36623, 7, 51.6–112.7 mm SL; MCP 46138, 1, 103 mm SL; MPEG 13083, 3, 116.4–127 mm SL; MPEG 28662, 5, 73.7–178.5 mm SL; MPEG 30901, 1, 103.7 mm SL; UFRGS 12165, 4, 105,5–97.7 mm SL; UFRGS 12325, 5, 49.8–133.6 mm SL; UFRGS 21842, 1, 100.3 mm SL; MNRJ 23380, 1, 115.4 mm