Southend Aquarist

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 borough status in southeastern Essex, England. It 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 town centre.

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Videos of the our Shows from 2001 to 2019 are available on www.vimeo.com/southendaquarist
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Two new species of the spiny percheel genus Mastacembelus (Synbranchiformes, Mastacembelidae) with low numbers of dorsal fin spines from the Congo basin,
Abstract
Two new species of African Mastacembelus are described with unusually low counts of dorsal fin spines. Until now the African species of spiny eels with the fewest dorsal fin spines are M. paucispinis Boulenger 1899, from mainstream rapids of the Lower Congo River, with 6-10 dorsal fin spines, well-developed eyes but obsolescent coloration, and M. sexdecimspinus (Roberts and Travers 1986) from high gradient rapids of Cross River, near Widekum, Cameroon, with 15-16 dorsal fin spines and well-developed coloration. The new species are M. ubangipaucispinis from mainstream rapids of the Ubangi River in the Congo basin, with 10 dorsal fin spines and well developed distinctive color pattern (similar to the obsolescent color pattern of M. paucispinis), and M. kadeiensis, from the Kadei River, Congo basin, Central African Republic, with 19 dorsal fin spines and a distinctive color pattern. The rest of African Mastacembelus have 21-40 dorsal fin spines and a different color pattern from the two new species. Mastacembelus ubangipaucispinis shows similarities with M. paucispinis, differing mainly in well-developed (versus poorly developed but otherwise similar) color pattern and in having fewer dorsal fin rays, 101 versus 115-123. Mastacembelus kadeiensis is perhaps most similar to M. sexdecimspinus and somewhat less closely to M. ubangipaucispinis and M. paucispinis. The holotype of Mastacembelus frenatus Boulenger 1901 from Lake Tanganyika reportedly has only 18 dorsal fin spines but coloration unlike M. kadeiensis. A radiograph reveals that it actually has 26 dorsal fin spines.
Full Text | PDF (128 KB)

Mastacembelus ubangipaucispinis n. sp., holotype, NRM 64699, 207 mm. a. lateral view; b. dorsal view; c. ventral view; d. radiograph lateral view.

from Aqua International

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Nothobranchius elucens • A New Species of Seasonal Killifish (Cyprinodontiformes: Nothobranchiidae) from the upper Nile drainage in Uganda

Nothobranchius elucens

DOI: 10.11646/zootaxa.4915.1.10

Abstract
Nothobranchius elucens, new species, from a seasonal habitat in the Aringa system of the Achwa River in the upper Nile drainage in northern Uganda, is described. It belongs to the N. rubroreticulatus species group, whose members are characterised by male coloration of anal and caudal fins with slender light blue subdistal band and slender dark distal band. Nothobranchius elucens is distinguished from all other members of the genus by the following characters in males: body colouration golden-grey with brown scale margins creating irregular vertical stripes on trunk; anal fin yellow with brown spots proximally, with slender brown median band, followed by a slender light blue subdistal band and a slender black distal band; caudal fin brown proximally and medially, followed by a slender light blue subdistal band and a slender black distal band; dorsal fin golden with irregular brown stripes and narrow light blue subdistal band and with narrow black distal band. Furthermore, it differs from the closest known relative, N. taiti, also by the morphometric characters of having a smaller head length of 29.5–33.1 % SL; smaller prepectoral length of 31.2–33.9 % SL; greater head depth of 81–87 % HL; greater interorbital width of 43–49 % HL; and greater caudal peduncle length of 145–152 in % of its depth.

Keywords: Pisces, Achwa River drainage, Madi Opei area, upper Nile ecoregion

Nothobranchius elucens, new species

Béla Nagy. 2021. Nothobranchius elucens, A New Species of Seasonal Killifish from the upper Nile drainage in Uganda (Cyprinodontiformes: Nothobranchiidae). Zootaxa. 4915(1); 133–147. DOI: 10.11646/zootaxa.4915.1.10

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Sillago nigrofasciata • A New Species of Sillago (Perciformes, Sillaginidae) from the southern Coast of China

Sillago nigrofasciata
Xiao, Yu, Song & Gao, 2021

DOI: 10.3897/zookeys.1011.57302

Abstract
A new Sillago species, the black-banded sillago, Sillago nigrofasciata sp. nov., is described based on 302 specimens sampled from the southern coast of China. Morphological comparisons have been conducted between the new species and ten other Sillago species. The results show that the new species is characterized by a black mid-lateral band below the lateral line when fresh; other characteristics are similar to those of Sillago sihama but subtle differences exist on the swim bladder between Sillago nigrofasciata sp. nov. and S. sihama. A detailed description and illustrations are provided for the new species. The validity of this new species is also supported by a genetic comparison using sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene.

Keywords: DNA barcoding, molecular phylogenetic analyses, morphology, swim bladder, taxonomy

Family Sillaginidae Richardson, 1846
Sillago Cuvier, 1817

Sillago nigrofasciata sp. nov.

Etymology: The specific name nigrofasciata is a compound adjective derived from the Latin words referring to the wide mid-lateral black longitudinal band of this species, a diagnostic character of the species.

Diagnosis: Relatively large body and usually with a wide mid-lateral black stripe from opercular to caudal peduncle; dorsal-fin rays X–XII (mostly XI), I+20–22, soft anal fin rays 20–22; scales in lateral line 67–75, scales above lateral line 4–6; gill rakers 2–4+5–8; vertebra: abdominal 14 or 15 (mostly 14), modified 3–7 (mostly 4 or 5), caudal 13–18, and total 34 or 35 (mostly 34) (Table 3). Swim bladder with two posterior extensions, the origin of the duct-like process at the terminus of swim bladder and start at the joint of roots of two posterior extensions (Fig. 4).

Habitat: Habitat is similar to S. sihama in nearshore areas and frequently entering estuaries for considerable periods, it is common along the beaches, sand bars, and mangrove creeks with sandy substrates. Depths ranging from 0 to 20 m, and frequently captured by trawling vessels.

Distribution: Sillago nigrofasciata sp. nov. was only found along the southern coast of China including the coastal waters of the South China Sea and the Taiwan Strait. Actually, its distribution range is similar to that of S. sihama in China (Fig. 1).

Jia-Guang Xiao, Zheng-Sen Yu, Na Song and Tian-Xiang Gao. 2021. Description of A New Species, Sillago nigrofasciata sp. nov. (Perciformes, Sillaginidae) from the southern Coast of China. ZooKeys. 1011: 85-100. DOI: 10.3897/zookeys.1011.57302

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Schistura hiranyakeshi • A New Loach (Cypriniformes: Nemacheilidae) from Maharashtra, Northern Western Ghats, India

Schistura hiranyakeshi
Praveenraj, Thackeray & Balasubramanian 2020

Schistura hiranyakeshi, a new species of loach is described from Hiranyakeshi River, Amboli, Sindhudurg district, Maharashtra. It is unique among congeners from peninsular, northeastern, and central India, and Sri Lanka in having an incomplete lateral line with 6-7 pores and ending at a point vertical at half the length of the adpressed pectoral fin; dorsal fin and caudal fin devoid of spots or blotches; body with 9-10 bars that are wider or almost equal in width to the interspaces; dorsal fin, anal fin and sub-dorsal bars with a unique crimson color in adult males; lower lip with a black mark on each side of the median interruption in live and preserved specimens; and no suborbital flap or axillary pelvic lobe.

Schistura hiranyakeshi

named after the Hiranyakeshi River drainage in Sindhudurg District of Maharashtra, India, where type locality (a temple pond fed by a natural spring from a laterite cave system) is situated; also, in Sanskrit, hiranyakeshi means “golden hair,” alluding to the golden-yellow coloration and body of adult specimens

Jayasimhan Praveenraj, Tejas Thackeray and Shankar Balasubramanian. 2020. Schistura hiranyakeshi A New Loach (Cypriniformes: Nemacheilidae) from Maharashtra, Northern Western Ghats, India. aqua - Int. Journal Ichthyol. 26(2)
https://aqua-aquapress.com/product/aqua-262_schistura-hiranyakeshi/
facebook.com/fishplorer/posts/10225718427173862
twitter.com/ranjeetnature/status/1316935857723637760
facebook.com/meenkaran/posts/3361462350636110

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GloFish Introduces Bettas to Fluorescent Fish Offerings

Premium male GloFish® Betta in Electric Green®. Image from Spectrum Brands, Inc.
via Spectrum Brands, Inc.
GloFish® LLC is welcoming a new species to its ever-expanding family of fluorescent fish with GloFish Betta. The Electric Green® GloFish Betta species is the first to debut within the betta category, introducing GloFish to a new audience, and will be available alongside a unique array of kits, species-specific food, water care, and decor.
GloFish Bettas offer a unique addition to the world of betta fish. While nearly identical in behavior to traditional domesticated bettas, GloFish Bettas produce a fluorescent protein that allows them to fluoresce under blue LED lights. And under white LED lights, their color is just as striking.
The Electric Green GloFish Betta livestock portfolio is comprised of:

Premium Male Betta – Full-grown male betta with impressive fins
Standard Male Betta – Young male with potential for fins to mature throughout its lifespan
Female Betta – As colorful as GloFish® male bettas, females are less aggressive than their male counterparts and can be kept with other female bettas, GloFish Tetras, Barbs, Danios and Sharks as well as other tropical fish.

Standard male GloFish Betta in Electric Green. Image from Spectrum Brands, Inc.
“Over the last several years, we have seen the popularity of GloFish grow, and we are thrilled to add to our livestock portfolio and introduce GloFish Bettas to the market, bringing the brand to an entirely new audience,” said Eric Kenney, Vice President, Marketing & Product Development at Spectrum Brands Global Pet Care Division. “Aside from offering eye-catching color hues, with more to come down the road, GloFish Bettas are easy to care for and fascinating to watch, making them an exciting addition to our portfolio.”
In addition to the livestock offerings, the brand is also introducing an assortment of products to elevate the aquatic experience, including 1.5 and 3 gallon Betta Aquarium Kits, Betta Flakes, Betta Water Conditioner and Betta Water Balance – with additional launches, including plants and other aquarium décor, later this year.
For more information on GloFish® products, visit www.glofish.com.

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International Betta Congress Issues GloFish Betta Policy

The International Betta Congress (IBC) is a worldwide union of Betta-lovers and breeders. It was founded in the United States in 1966 by Dr. Gene Lucas (known as the father of the IBC) and others as a non-profit organization with the goal of promoting bettas and researching them.
via International Betta Congress (IBC)
Official Notice from the Judging Board
05 February 2020
With the advent of GloFish® Bettas coming into the market the IBC is issuing an official policy as to the use of GloFish® Bettas in the IBC and for IBC Shows. Below is the official policy of the use of GloFish®
Electric Green® GloFish® male betta. Image from 5-D Tropicals.
GLOFISH® FLUORESCENT FISH LICENSE NOTICE
GloFish® fluorescent ornamental fish are intended solely for visual enjoyment as aquarium fish by end-users who have purchased these fish through authorized channels, and not for commercial reproduction. Please note the following important information:
These fish are the subject of various intellectual property rights owned or controlled by GloFish LLC, both in the U.S. and internationally.
GloFish® is a trademark owned by GloFish LLC (Registration No. 3,056,697) and cannot be used in connection with the promotion or sale of any ornamental fish other than authentic GloFish® fluorescent fish, which are exclusively produced by Segrest Farms, Inc. and 5-D Tropical, Inc. for sale on behalf of GloFish LLC.
GloFish® fluorescent fish are covered under one or more of the following United States Patent Numbers: 7,834,239; 7,858,844; 7,700,825; 7,135,613; 7,442,522; 7,537,915; 7,150,979; 7,166,444, 8,153,858; 8,232,450; 8,232,451; 8,378,169; 8,581,023; 8,581,024; 8,581,025; 8,975,467; 8,727,554; and 8,987,546, as well as other pending applications.
Intentional breeding and/or any sale, barter, or trade, of any offspring of GloFish® fluorescent ornamental fish is strictly prohibited.
Notwithstanding the foregoing, production of these fish is permitted for educational use by teachers and students in bona fide educational institutions, provided, however, that any sale, barter, or trade, of the offspring from such reproduction of these fish is strictly prohibited.
Any bag, container, or aquarium holding GloFish® fluorescent fish for resale, other than bags provided to end-users, will be marked with either “GloFish® fluorescent fish”, or “GloFish®”, along with the name of the specific line(s) being held (i.e., Starfire Red®, Electric Green®, Sunburst Orange®, etc.). The IBC will honor all agreements that exist with the GloFish® Betta an end-users. As such.

GloFish® Bettas are only allowed to be shown in the purchased fish category
GloFish® Bettas shown in any other class will be automatically disqualified as it is a violation of the user agreement on reproducing the Glo Betta
GloFish® Bettas are not to be auctioned off at any IBC event so that the IBC does not unintentionally violate the sales policy on Glo Bettas.
The agreements with the GloFish® Betta manufactures will be honored, and no classes will ever be constructed for GloFish® Bettas unless that class is constructed under the Purchased fish Category at the discretion of the IBC Judging Board.

We at the IBC hope you do understand and honor these agreements. Infractions will be dealt with in an appropriate manner as outlined in the IBC Handbook as needed by the Judging Board and the Executive Board.
Gerald Griffin
Judging Board Chair

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First Captive Breeding of the “Freshwater” Top Hat Blenny

The Top Hat Blenny, Omobranchus fasciolatoceps, is an inshore species often marketed to freshwater aquarists. This image by Mike Jacobs, courtesy of Nautilus Wholesale.
This latest captive-breeding accomplishment highlights an interesting and occasionally-seen fish that is usually imported and distributed as part of the freshwater aquarium trade.
The Top Hat Blenny, Omobranchus fasciolatoceps, is one of a few species of blenniid fishes that are sometimes marketed to aquarium keepers as “Freshwater Blennies.” This native of Japan, Taiwan, Hong Kong, and the overall southern China coast is found in estuaries and the ocean shallows near shore. It reaches a modest 3 inch (8 cm) length and is likely tolerant of a wide range of temperatures; Fishbase goes so far as to consider this a “temperate” species. Not overly aggressive but certainly not timid or passive, the species will likely be a fascinating aquarium inhabitant. Its fleshy crest and zebra-striped face make this substrate dweller all the more appealing. Blennies are known as fish with personalities, and the Top Hat Blenny certainly lives up to that expectation.
Early Research
Earlier larval research published in 1999 successfully demonstrated the successful larval rearing of the Omobranchus faciolatoceps in a laboratory setting. Takamitsu Kawaguchi, Hiroshi Kohno, Kiyoshi Fujita, and Yasuhiko Taki collected clutches of wild eggs, which were then subsequently hatched and reared in “50% seawater” at temperatures of 77–86F (25–30C). Nannochloropsis algae, rotifers (Branchionus plicatilus), and brine shrimp (Artemia salina) were used in the larval rearing process. The researchers’ findings were published in the journal Ichthyological Research, June 1999, and are currently available for online reading.
Of note, the eggs are laid in concealed places (caves, holes, oyster shells) and are apparently guarded by the male blenny in the wild. The eggs hatch into larvae that are approximately 3 mm in body length (BL). Flexion starts at just over 5 mm BL and is completed by the time the larvae have reached 7 mm BL. At a length of just under 10 mm BL, the larvae are fully-finned they and transition into the juvenile stage. By around 18 mm BL (roughly 0.75 inches), the fish show color patterning.
A Captive-Bred First
Over 20 years later, Pei-Sheng Chiu, an assistant researcher at the Mariculture Research Center, Fisheries Research Institute, Taiwan, has revisited the species and taken the breeding of Top Hat Blennies one step further. Chiu found the missing element that defines a “captive-bred” fish, successfully spawning the species in an aquarium and rearing the larvae through to the juvenile stage. As such, we would argue that this marks the first true successful captive breeding of the species.
Chiu noted that he believes all the specimens in the Taiwanese aquarium trade are wild-caught. He clearly conveyed that, “This species is a marine fish, which should ideally breed in seawater, but it can be kept in freshwater and brackish water. Broodstock can spawn in seawater, brackish water, and freshwater, but the hatchability of fertilized eggs was significantly lower in freshwater.”
Through personal conversation, Chiu helped fill in some of the gaps from prior research. There may be some dimorphism and dichromatism in O. faciolatoceps; Chiu’s broodstock pair clearly shows the female as smaller and more colorful. Males do undergo a color change during courtship.
Broodstock pair, with male on left and smaller, more colorful female on right. Image credit: Pei-Sheng Chiu

Egg of the Top Hat Blenny, near hatching. Image credit Pei-Sheng Chiu
The time from spawn to hatch has not been disclosed.
Larval Top Hat Blennies. Image credit Pei-Sheng Chiu

A fully formed juvenile Tophat Blenny. Image credit Pei-Sheng Chiu
Chiu reported that rotifers were used as the first food (in this instance, Brachionus ibericus), and that “the feeding method is similar to most clownfish.” Growout times were not disclosed.
A juvenile Tophat Blenny with coloration more developed. Image credit Pei-Sheng Chiu

Dozens of captive-bred Top Hat Blennies. Image credit Pei-Sheng Chiu
What’s Next?
Chiu’s documentation and formalized findings will be submitted to a scientific journal for publication in Taiwan. Outwardly, these reports suggest that the Top Hat Blenny may make a great candidate for home-based breeding efforts. This also lends support to the general suitability of this species for aquarium-keeping, adding yet another good candidate species to the niche “brackish fish” market. The fish may be able to thrive at any salinity.
Joe Hiduke, Sales Manager for Nautilus Wholesale, agrees. “They’ve always done great for me; seem to be very hardy. We keep them around 5ppt for salinity. I got a handful to our salt supplier, and they did well in full saltwater too.”
A closer look at the juvenile captive-bred Tophat Blennies. Image credit Pei-Sheng Chiu
Other species of Omobranchus may be encountered in the aquarium trade, including the Brachiosaurus Blenny, Omobranchus anolius, which is exported from Australia on occasion and marketed as a marine offering, or the Zebra Blenny, Omobranchus zebra, being marketed as a freshwater or brackish species, exported from India. All these species are found in near-shore habitats (mudflats, mangrove estuaries, bays, rocky shorelines), and as such may all have some tolerance of varying salinity levels. They might also share similar reproductive strategies and breeding requirements. Clearly, this is a genus ripe for further investigation by aquarists!

References
Pei-Sheng Chiu’s initial announcement on Facebook -> https://www.facebook.com/groups/Marinebreeding/permalink/2639558366330141/
Kawaguchi, T., Kohno, H., Fujita, K. et al. Early morphological development of Omobranchus fasciolatoceps and O. punctatus (Blenniidae: Omobranchini) reared in an aquarium. Ichthyological Research 46, 163–170 (1999). https://doi.org/10.1007/BF02675434

from Reef To Rainforest
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New Species of Hill-Stream Betta

Male (top) and female Betta nuluhon. Image from Kamal, Tan, and Ng 2020.
There is a new Betta known to science! Authors Kamal, Tan, and Ng (2020) recently described a new species of hill-stream Betta native to Malaysia in the journal Zootaxa.
To some, the thought of a typical fighting fish habitat produces imagery of slow-moving perhaps even stagnant waters. But this is not the case for the newly described Betta nuluhon. Discovered in the Malaysian state of Sabah, B. nuluhon was once thought to be a variety of B. chini, a resident of lowland peat-swamps in western Sabah. The new species, however, was located in the hill streams of the Crocker mountain range (exact coordinates were not provided to prevent illegal collection). The specific epithet is based on the indigenous Kaduzandusun word for “hill”.
Physical description
Betta nuluhon are brown to dark brown with body scales rimmed with bright blue. A dark stripe extends from the upper jaw through the eye to the opercle edge, a dark suborbital stripe and a chin bar are present. The body consists of a yellow dorsal region, black lateral regions, and a reddish ventral region. Male B. nuluhon may exhibit a greenish-blue iridescence on the opercle. The dorsal fin is brown with 4 to 6 traverse bars, the caudal fin has 12 to 16 dark transverse bars, the anal fin is plain with a reddish-brown margin, and the pelvic fin has a whitish second filamentous ray. The fish examined for this study had standard lengths from 39.8 to 62.6 mm.
Betta nuluhon, 50 mm SL male. Image from Kamal, Tan, and Ng 2020.
Ecology
Specimens were collected inside the Crocker Range Forest Reserve in a shallow clear-water stream that had overhanging riparian vegetation and a combination of pebble, sand, and silty substrate. At the time of collection, the water had a temperature of 75°F (24°C), a pH of 6.57, and a dissolved oxygen concentration of 6.25 mg/L. Also present in the collection locale were giant mottle eels (Anguilla marmorata), Bornean spotted barbs (Barbodes sealei), Nematabramis borneensis, Tor tambra, and Gastromyzon introrsus.
Like other members of the Betta akarensis species-group, B. nuluhon are male oral mouthbrooders.
A comparison of a 58.6 mm SL male B. chini (top) to that of a 62.6 mm SL male B. nuluhon. Image from Kamal, Tan, and Ng 2020.
Reference:
Kamal, N.S.S., H.H. Tan, and C.K.C. NG. 2020. Betta nuluhon, a new species of fighting fish from western Sabah, Malaysia (Teleostei: Osphronemidae). Zootaxa 4819 (1): 187–194.
Article Abstract:
Betta nuluhon, a newly described species, is from a hill stream habitat in western Sabah. This species is allied to both B. chini and B. balunga, and differs from the rest of its congeners in the B. akarensis group by having the following combination of characteristics: yellow iris when live; mature males with greenish-blue iridescence on opercle when live; mature fish with distinct transverse bars on caudal fin; slender body (body depth 22.1–25.2 % SL); belly area with faint reticulated pattern (scales posteriorly rimmed with black); absence of tiny black spots on anal fin; lateral scales 29–31 (mode 30); predorsal scales 20–21 (mode 20). Notes on a fresh series of B. chini are also provided.

from Reef to Rainforest.
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Following the Mangroves: diversification in the banded lampeye Aplocheilichthys spilauchen (Duméril, 1861) (Cyprinodontiformes: Procatopodidae) along the Atlantic coast of Africa

P. H. N. Bragança,
J. Van der Zee,
A. Chakona,
R. C. Schmidt &
M. L. J. Stiassny

Hydrobiologia (2021)Cite this article

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AbstractAvailable ecological information, an extensive distributional range, conflicting osteological data, and a proposed early Miocene origin provide the impetus for the present study which investigates genetic structuring, biogeographic, and phylogenetic relationships within the Aplocheilichthys spilauchen lineage. Through the analysis of the mitochondrial gene COI, species delimitation methods (ABGD, GB, GMYC, bPTP) were applied, recognizing 6–7 OTUs with absolute pairwise genetic distances ranging between 8 and 22%. The onset of diversification is estimated to be within the middle Miocene and both dispersal and vicariance-shaped A. spilauchen diversity and distribution, as suggested by time-calibrated and ancestral range reconstruction (S-DIVA) analyses. We report for the first time, a pattern of diversification within a lineage of brackish water fish that is concordant with the historical distribution of coastal mangroves forests, shaped by a series of historical events that likely affected forest cover since the middle Miocene (e.g. major climate shifts and sea-level fluctuations, onset of the modern Congo River outlet, increased volcanism in the Cameroon Volcanic Line).
IntroductionMangrove forests are among the most dynamic habitats in tropical and subtropical intertidal zones, where they are limited to low-lying coastal areas with constant input of freshwater (Kathiresan & Bingham, 2001; Duke, 2017). Along the African Atlantic coast, the latitudinal extent of mangroves is constrained by two cold sea currents, the Benguela Current in the south, flowing northwards from South Africa to Angola, and the Canary Current flowing southwards from Morocco to Senegal (Saenger & Bellan, 1995) (Fig. 1). The presence and extent of mangrove stands in Africa are directly related to humidity, rainfall, and coastal relief and are known to have undergone extensive expansions and contractions in both range and abundance over time (Saenger & Bellan, 1995). Indeed, the study of mangrove cover is a primary source of information for modelling impacts of climate change (Alongi, 2015), as well as for palaeoclimatic reconstructions based on historical data from mangrove pollens (Bonefille et al., 1982; Leroy & Dupont, 1994; Scourse et al., 2005; Durogbo et al., 2010; Adeonipekun et al., 2016; Vallé et al., 2017).
Fig. 1
Map of West and West-Central Africa with mangrove distribution (light green) and Aplocheilichthys spilauchen sampling sites (black dots) indicated. AC Angola Current, AR Atlantic Rise (red), BC Benguela Current, CC Canary Current, CVL Cameroon Volcanic Line (yellow bar), FP Freshwater plume (blue), GC Guinea Current, GGC Gulf of Guinea Current, SEC South Equatorial Current. Arrows indicate currents direction

Full size imageThe Atlantic coast of Africa has an extremely narrow continental shelf, resulting in mangrove expansion during high sea level but contraction during low sea level (Saenger & Bellan, 1995; Scourse et al., 2005). In a high sea-level scenario, mangroves expand over new floodplains along the lower sections of rivers newly under tidal influence and salinity. In the opposite low sea-level scenario, fewer surfaces are exposed and mangroves recede to the newly reduced tidal zone, with the original stands replaced by other vegetation types. This is in contrast to regions with wide continental shelves, such as in Southeast Asia where significant mangrove expansion is related to low sea level, as shallow shelf areas previously covered by saltwater are exposed to tidal influence and freshwater inputs (Luther & Greenberg, 2009). A similar pattern is seen along the Brazilian coast, also with a wide continental shelf, where during periods of low sea level, many brackish water palaeochannels form and connect adjacent river drainages providing ideal conditions for mangrove expansion (Thomaz et al., 2015; Thomaz & Knowles, 2018). Similar to the described mangrove dynamics, the distribution of brackish water fishes is also highly dependent on freshwater inputs from effluent river systems and sea-level variations (Saenger & Bellan, 1995; Kathiresan & Bingham, 2001; Duke, 2017). Such alternating expansion and contraction dynamics can reveal interesting historical information when analysed in phylogenetic and temporal contexts, and this is particularly the case for taxa inhabiting regions known for major shifts in river outflows, climatic instability, sea level changes, and tectonic activity such as along the African Atlantic coast (Giresse, 2005; Goudie, 2005; Runge, 2007; Flugel et al., 2015).
Among the procatopodids, a cyprinodontoid group comprising mainly freshwater fishes endemic to Africa, the banded lampeye, Aplocheilichthys spilauchen (Duméril, 1861), is one of the few brackish water species and is a dominant species in mangrove habitats along the tropical and subtropical zones of the Atlantic coast (Fig. 1). Similar to other procatopodids and many other cyprinodontoids, A. spilauchen is known for a well-developed swimming capability (vagility) when compared to members of the Aplocheiloidei that in Africa are represented by the Nothobranchiidae (Huber, 1999). The latter is found mostly in shallow freshwater habitats, and some taxa even exhibit a seasonal life cycle (e.g. Nothobranchius), thus, presenting a completely different response to climatic and biogeographic processes. A river or an increase in the input of freshwater into an estuarine region likely represents range expansion opportunities for cyprinodontoid taxa, whereas for aplocheiloids, they more likely act as barriers (Bartáková et al., 2015).
Although A. spilauchen has also occasionally been collected from inland freshwater habitats, it primarily has a coastal distributional range, which closely mirrors the area covered by Atlantic coast mangrove forests, from the Senegal River to the Kwanza River in Angola (Wildekamp, 1995; Saenger & Bellan, 1995; Feka & Morrison, 2017) (Fig. 1). Aplocheilichthys spilauchen is currently recognized as the sole member of Aplocheilichthys and was the first African lampeye to be described (as Poecilia spilauchen), based on specimens from the Ogowe River in Gabon by Duméril (1861). It is readily distinguished from all other procatopodids by the presence of a combination of vertical grey banding along the flanks and dorsal, anal, and caudal fin in males and attainment of large body size (Fig. 2). Adults routinely reach up to 7.0 cm standard length while other procatopodids rarely exceed 4.0 cm standard length (Wildekamp, 1995). Likely, due to this distinctive pigmentation patterning and its presence in mangroves and other brackish water habitats, it has been assumed that A. spilauchen is a widely distributed species. Two other species, A. typus Bleeker, 1863 probably from Ghanaian coastal regions (Wildekamp, 1995), and A. bensonii (Peters, 1864) from Liberia were described but promptly synonymized with A. spilauchen by Günther (1866). A third species, A. tschiloangensis Ahl, 1928, described from the Tschiloango River in Cabinda, an Angolan territory north to the Congo River outlet, is now also considered a synonym of A. spilauchen (Huber, 1982; Wildekamp et al., 1986).
Fig. 2
Males of A. spilauchen from localities along the Atlantic coast of Africa: a UFRJ 4150, 37.6 mm SL, Sangrougrou River, Senegal; b AMNH 275472, 51.0 mm SL, Farmoriah River, Guinea; c AMNH 59382, 52.8 mm SL, Freetown, Sierra Leone; d UFRJ 11487, 44.8 mm SL, Assimie, Ivory Coast; e MRAC 73–08-P-135–138, 41.0 mm SL, Ebrie Lagoon, Ivory Coast; f AMNH 226603, 46.4 mm SL, coastal Benin; g UFRJ 11484, 42.3 mm SL, coastal Nigeria (aquarium import); h MRAC 143378–387, 64.7 mm SL, Bioko Island, Equatorial Guinea; i MRAC 73–39-P-2168–179, 41.4 mm SL, mouth of Mirupururu River, Bioko Island, Equatorial Guinea; j AMNH 258331, 45.5 mm SL, mouth of Kouilou River, Republic of Congo; k AMNH 238526, 31.0 mm SL, Boma estuary, lower Congo River, Congo DRC; l SAIAB 84605, 40.0 mm SL, Dondo, Kwanza River, Angola

Full size imageInvestigating seasonal variations in mangrove fish communities in Nigeria, Wright (1986) found that A. spilauchen was the dominant species, both in numbers and biomass and that its reproductive cycle was dependent upon freshwater inputs. Okyere (2012), in a study evaluating the use of A. spilauchen for mosquito larvae control along the Ghanaian coast, found that the species exhibited a low resilience to salinity increase, tolerating only a maximum of 4‰ salinity (Okyere, 2012). Both ecological studies suggest a dependence on freshwater in shaping the niche requirements and distribution of the species. Osteological information available for A. spilauchen reveals some inconsistencies regarding the configuration of the hypural plate supporting the caudal fin, usually an invariant feature among procatopodid species. The plate was considered as completely fused (Parenti, 1981), separated (Ghedotti, 2000), or bearing a small gap close to the compound caudal centrum (Costa, 2012).
Recently, in the first molecular dated analysis focused on the Procatopodidae, A. spilauchen was resolved as the sole member of a lineage sister to all other procatopodids, except Plataplochilus Ahl, 1928 (Bragança & Costa, 2019). Through the inclusion of two fossil calibrations in the sister families Valenciidae and Aphaniidae, it was estimated that A. spilauchen split from the remaining procatopodids in the early Miocene (around 23 mya). Considering the diversification patterns seen in all other procatopodid lineages, which intensified during the middle/late Miocene and Pliocene, the presumed lack of diversification within the A. spilauchen lineage is worthy of investigation.
Available ecological information (Wright, 1986; Okyere, 2012), conflicting osteological data (Parenti, 1981; Ghedotti, 1998, 2000; Costa, 2012) and a proposed early Miocene origin for the A. spilauchen lineage (Bragança & Costa, 2019) provide the impetus for the present study which aims to (1) investigate cryptic diversity within the A. spilauchen lineage through the application of both distance and coalescent species delimitation methods, (2) examine connectivity or genetic structuring between haplotypes, (3) estimate the divergence times for identified lineages, (4) perform ancestral area reconstructions, and (5) interpret the resulting temporal and biogeographic patterns in view of the current knowledge of the main historical events that have affected the African landscape and influenced Atlantic mangroves and coastal habitats.
Material and methodsSpecimen preservation and fixationSamples were collected using a variety of fishing techniques, and specimens were euthanized with clove oil or MS-222 anaesthetic solutions, in accordance with recommended guidelines for the use of fishes in research (Bennett et al., 2016). A small piece of muscle tissue or fin was taken from the right side of each specimen, or the entire fish was preserved in 95% ethanol in the field. The samples were stored at low temperatures at each of the following institutions: (1) NRF-South African Institute for Aquatic Biodiversity (NRF-SAIAB), Makhanda (Grahamstown), South Africa; (2) Ichthyological Collection of the Biology Institute of the Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil; (3) Royal Museum for Central Africa (RMCA), Tervuren, Belgium; (4) American Museum of Natural History (AMNH), New York, USA; (5) National Museum of Natural History (USNM), Washington, USA and (6) Oregon State University (OS), Corvallis, USA.
Taxon samplingSamples of newly generated and published sequences of the mitochondrial gene COI (Cytochrome c oxidase subunit 1) with a total of 679 bp from eight populations of A. spilauchen from across its geographical range were included in the analysis (Fig. 1). The present dataset includes samples from the (1) Kwanza and Lucala rivers in Angola (n = 7); (2) lower Congo River in the Democratic Republic of Congo (n = 2); (3) Kouilou River in the Republic of Congo (n = 2); (4) Ngounie River (Ogowe River drainage) and Komo river in Gabon (n = 3); (5) Ntem River in Equatorial Guinea (n = 3); (6) Aquarium import specimens from coastal Nigeria (n = 2); (7) Kakum River in Ghana (n = 3) and (8) Forecariah River at Conakry, Guinea (n = 2). Following Bragança & Costa (2019), three species were selected as outgroups: Plataplochilus miltotaenia Lambert, 1963 and P. pulcher Lambert, 1967, representing the first diverging lineage of the Procatopodidae and ‘Poropanchax’ normani (Ahl, 1928), representing the remaining procatopodid lineages sister to Aplocheilichthys. The generic name of ‘Poropanchax’ normani is between quotation mark to indicate that the species is not a member of Poropanchax sensu stricto as revealed in Bragança & Costa (2019), and awaits future taxonomic and nomenclatural resolution. A list of all included specimens and their respective catalogue numbers, localities, and GenBank Accession numbers are provided in Table 1. Other specimens, not included in the molecular analyses but photographed to illustrate pigmentation and body shape variation in different populations along the African coast, are shown in Fig. 2. The catalogue number and locality information of the specimens in Fig. 2 are listed in Online Resource 1.
Table 1 Species localities and Genbank and Bold Accession numbers: numbers in bold refer to sequences developed in the present study
Full size tableDNA extraction and sequencingDNA was extracted from preserved tissues using the salting out method (Sunnucks et al., 1996), or the DNeasy Blood & Tissue Kit (Qiagen, Hilden) following the manufacturer’s standard protocol for animal tissue isolation. A fragment of the mitochondrial gene COI (Cytochrome c oxidase subunit 1) was amplified with universal primers LCO1490 and HCO 2198 and published protocols (Folmer et al., 1994). PCR products were purified with Exosap (Applied Biosystems), cycle sequenced using BigDye Cycle Sequencing Kit (Applied Biosystems, Foster City, CA, USA) and sequenced at the NRF-SAIAB using an ABI 3730xl DNA Analyzer (Applied Biosystems), or by Macrogen, South Korea.
Phylogenetic analyses, COI codon partitioning and evolution modelsPhylogenetic analyses included newly generated and published sequences of the mitochondrial gene COI from A. spilauchen specimens from along the western coastal plains and mangroves of the Atlantic coast (see Table 1). Our COI alignment did not have frameshifts, indels or premature stop-codons, which are indicative of pseudogenes. The best models of evolution for each codon position for the maximum likelihood (ML) and Bayesian inference (BI) analyses were determined in PartitionFinder2 (Lanfear et al., 2016). The partitioned ML analysis was completed with GARLI (Zwickl, 2006), and bootstrap support was assessed from a majority rule consensus tree generated in Mesquite (Maddison & Maddison, 2019) from 1000 trees. The partitioned BI analysis was performed with MrBayes version 3.2 (Ronquist et al., 2012), and posterior probabilities were assessed with 5 million generations, sampling trees every 1000 generations. The first 25% of trees were discarded as burn-in. Both the ML and BI analyses were performed on the CIPRES Science Portal (Miller et al., 2010). The models of evolution implemented for each codon position in the ML and BI analyses were TRNEF + I + G, F81 + I, and TIM + G and SYM + G, F81 + I, and GTR + G, respectively.
For the species delimitation methods (described below), an ultrametric tree including only unique haplotypes (n = 15) as required by the GMYC method was performed in Beast 1.8.2 (Drummond et al., 2012), and the parameters were defined as follows: an uncorrelated relaxed clock model with a lognormal distribution (Drummond, et al., 2006), with 10 million generations with a sampling frequency of 1000. The value of parameters of the analyses, convergence of the MCMC chains, sample size and the stationary phase of chains were evaluated using Tracer 1.6 (Rambaut et al., 2014). A Birth and Death Incomplete Sampling speciation process for the tree prior (Stadler, 2009), indicated for datasets with incomplete sampling, was used, and the analysis included only ‘Poropanchax’ normani as outgroup. For this analysis, the evolution model HKY + G was inferred in JModeltest (Darriba et al., 2012) for the entire COI gene. Saturation levels were checked in Dambe5 (Xia, 2013), according to the algorithm proposed by Xia et al. (2003).
Species delimitationFour species delimitation methods were applied to investigate the diversity within A. spilauchen. The traditional barcoding genetic distance method (GD) (Herbert et al., 2003) and the Automatic Barcode Gap Discovery (ABGD) (Puillandre et al., 2012), both relying on genetic distances between haplotypes, and the General Mixed Yule Coalescent (GMYC) (Fujisawa & Barraclough, 2013) and Bayesian implementation of the Poisson Tree Processes (bPTP) (Zhang et al., 2013), both coalescence approaches.
For the GD method, we used the Kimura-2-parameters model (K2P) (Kimura, 1980) to estimate the pairwise genetic distances between the different A. spilauchen populations in MEGA 7 software (Kumar et al., 2016). Haplotypes with a genetic divergence higher than 3% were considered as belonging to distinct operational taxonomic units (OTUs) following the expected pattern for genetic divergence between fish species (Ward, 2009). ABGD also relies on genetic distances to identify the threshold between interspecific (speciation) and intraspecific (populational) processes within the dataset (Puillandre et al., 2012). The main difference between GD and ABGD is that the ABGD allows a more refined search; once the estimated genetic divergence between groups (putative species) is calculated, it is recursively applied to the previously delimited groups until no more putative OTUs are recognized. The ABGD result is presented relative to a spectrum of P values (prior intraspecific values) in which a 0.001 value assumes a minimum intraspecific variability, and a 0.1 value assumes a maximum intraspecific variability. The different results relative to each significant P value intervals are presented, and to identify which P value interval best describes the diversity within the dataset, a congruence with other methods is expected and/or a support from traditional morphological alpha taxonomy. The ABGD analysis was performed in the ABGD server website (https://bioinfo.mnhn.fr/abi/public/abgd/abgdweb.html) following the default parameters.
The coalescence species delimitation method, GMYC (Fujisawa & Barraclough, 2013), requires an ultrametric tree to distinguish between intraspecific (coalescent) and interspecific (speciation) threshold patterns, because it relies on branch length differences to define OTUs. The bPTP coalescent method (Zhang et al., 2013), in contrast to GMYC, relies on the number of nucleotide substitutions between haplotypes to resolve intraspecific and interspecific patterns. When performing bPTP, two results are provided, the BI and the ML solutions, and in each, the recognized OTUs are depicted graphically in a tree. The same reduced dataset tree as for GMYC was used when performing bPTP. The GMYC analysis was performed on the Exelixis Lab's server https://species.h-its.org/gmyc/ following default parameters, and the bPTP was performed on the Exelixis Lab's server https://species.h-its.org/ptp/ following default parameters except for a 20% burn-in.
Haplotype networkThe haplotype network was inferred, using the Minimum Spanning Network method (Kruskal, 1956) in PopART 1.7 (Leigh & Bryant, 2015), including only A. spilauchen haplotypes. The following eight geographic areas/drainages were delimited: (A = Gabon, B = Angola, C = Guinea, D = Kouilou, E = Lower Congo, F = Nigeria, G = Ghana, H = Equatorial Guinea). These areas were delimited based on the presence or absence of connectivity between haplotypes as suggested by the genetic divergence and species delimitation results. Therefore, the area ‘Angola’ includes all haplotypes from the Kwanza and Lucala rivers, the latter being one of the main tributaries of the lower Kwanza River. The area ‘Gabon’ includes all haplotypes from the Ngounie River, a tributary of the lower Ogowe River, and from the Komo River.
Time-calibrated analysisThe time-calibrated analysis was constructed in BEAST v.1.8.2 (Drummond et al., 2012), including all sequences available, and an uncorrelated relaxed clock model with a lognormal distribution (Drummond et al., 2006). Bayesian Inference was performed with 50 million generations with a sampling frequency of 1000. The values of parameters of the analysis, convergence of the MCMC chains, sample size, and the stationary phase of chains were evaluated using Tracer 1.6 (Rambaut et al., 2014). The same Birth and Death Incomplete Sampling speciation process was selected for the tree prior (Stadler, 2009). Since no fossil procatopodids are currently known three relevant calibration points based on the age estimates from Bragança & Costa (2019) were selected. These secondary calibrations correspond to (1) the Procatopodidae basal node (prior setting: normal distribution, mean = 30.1, standard deviation = 1.3); (2) the node representing the split between the A. spilauchen clade and ‘Poropanchax’ normani (prior setting: normal distribution, mean = 23.1, standard deviation = 1.5); and (3) the node representing Plataplochilus diversification (prior setting: normal distribution, mean = 3.2, standard deviation = 0.9). A normal distribution prior was selected for the secondary calibration points as recommended by Ho (2007) and Ho & Phillips (2009). At the end of the analysis, a burn-in of 25% of the retained trees was performed in TreeAnnotator.
Ancestral area reconstructionThe ancestral area reconstruction method, S-DIVA (Statistical Dispersal-Vicariance Analysis) (Yu et al., 2010), was performed in RASP 3.2 (Yu et al., 2015) to reconstruct the expected ancestral areas during A. spilauchen diversification. S-DIVA is an event-based method that incorporates statistical uncertainty into both phylogenetic and ancestral state reconstructions and assumes vicariance as the most probable event to explain biogeographical evolution within a group, attributing higher costs for dispersal and extinction events. For the S-DIVA analysis, both extinctions and reconstructions were considered, and at each node, the frequency of alternative ancestral area reconstructions generated for each tree in the dataset is shown. The analysis was performed on the resulting trees from the time-calibrated analysis from Beast 1.8.2 (Drummond et al., 2012), and the condensed tree was defined as the summary tree from that same analysis. Prior to the analysis, the outgroups were removed in RASP 3.2, and a post-burning of 12,500 trees was carried out. The maximum number of areas included in ancestral distributions was set to 3, but based on current knowledge from ecology, distribution, and genetic divergence between populations, only ancestral distributions between contiguous areas were allowed.
ResultsPhylogenetic analysis (Online Resource 2)ML and the BI analyses recovered the same topology with most nodes receiving posterior probability values > 95 and bootstrap values > 80, except for nodes representing the most recent divergences (Online Resource 2). An early divergence of Plataplochilus species and a sister group relationship between the A. spilauchen lineage and ‘Poropanchax’ normani were recovered with strong support. Within Aplocheilichthys, a sister group relationship between haplotypes from Ghana and Guinea was supported with a high posterior probability but a comparatively lower bootstrap value (Online Resource 2). Haplotypes from Gabon were resolved as sister to all remaining haplotypes with high support. Another node, also strongly supported, represents the split between Nigerian + Equatorial Guinean haplotypes from those from Kouilou, lower Congo, and Angola. A sister group relationship between Nigerian and Equatorial Guinean haplotypes was supported by maximum values in both analyses. The node-grouping haplotypes from Kouilou, lower Congo and Angola were supported with high posterior probability but a comparatively lower bootstrap value. However, within that clade, all nodes received lower support values, except the node representing the split between Kouilou haplotypes and those from lower Congo and Angola, which received strong support.
Species delimitation (Fig. 3)Fig. 3
Ultrametric tree and OTUs delimited by each species delimitation method (represented by different colours). Numbers indicate posterior probability values

Full size imageBoth genetic distance methods provided similar results, but as expected, with a decrease in intraspecific variability value (P value) in ABGD more OTUs were delineated. The ABDG result with a P value between 0.0129 and 0.0599 recovered the same six OTUs as delimited by the GD method: (1) Ghana, (2) Guinea, (3) Gabon, (4) Nigeria, (5) Equatorial Guinea, (6) Kouilou + lower Congo + Angola, whereas one more OTU was identified between P values of 0.0046 and 0.0077, with the Kouilou lineage considered as distinct from a lower Congo + Angola OTU. The absolute pairwise genetic distances for the OTUs identified based on the GD method range from 8 to 22%, which are considerably higher than the heuristic standard threshold of 2–3% commonly applied to recognize species limits (Table 2). The highest genetic distance (22%) was between specimens from Guinea and Equatorial Guinea while the lowest (2%) was recorded for specimens from Kouilou, lower Congo and Angola.
Table 2 Genetic distance within A. spilauchen haplotypes conducted using the K2-parameter model in MEGA 7
Full size tableThe Bayesian ultrametric tree (Fig. 3) had the same topology as the phylogenetic analyses (Online Resource 2), with most nodes supporting putative OTUs with maximum posterior probability values. There was concordance of the six OTUs defined by ABGD (P value between 0.0129 and 0.0599), GD, GMYC and the bPTP ML solution result, while bPTP BI solution returned the same seven OTUs as ABGD when assuming the lowest P values. We considered the six OTUs defined by the traditional barcoding, the ABGD including P values between 0.0129 and 0.0599, the GMYC and the bPTP ML solution as putative species but defer making any taxonomic changes pending a detailed osteological and morphometric study (see Discussion).
Haplotype network (Fig. 4b)Fig. 4
a Map showing the sampled localities and the male colouration in life at each site; b mitochondrial gene COI Minimum Spanning haplotype Network for A. spilauchen haplotypes. The number of nucleotide changes is indicated in parentheses

Full size imageA minimum spanning network portraying genealogical relationships among haplotypes revealed considerable divergence between geographically separated populations within A. spilauchen. In most cases, the number of nucleotide substitutions separating populations was extremely high ranging from a minimum of 43 up to 133. The only exception to this being among haplotypes from the neighbouring Kouilou, lower Congo, and Angolan populations which form a cluster with a maximum of 12 nucleotide changes separating Kouilou haplotypes from the Angolan and lower Congo haplotypes.
Time-calibrated analysis (Fig. 5)Fig. 5
Time-calibrated phylogeny of the Procatopodidae and A. spilauchen obtained from the Bayesian dating analysis in BEASTv.1.8. Bars represent maximum and minimum date estimates for each node (values in brackets), and the numbers are nodes divergence mean ages. The colours in the time bar are a reference to the proposed time extension of main palaeogeographic and palaeoclimatic events during A. spilauchen evolution: the green bar represents the Miocene Climatic Optimum; the red bar represents the Miocene Climatic Transition; the orange bar represents the late Miocene aridification; the brown bar represents the Pliocene–Pleistocene climatic instability; the blue bar represents the onset of the modern Congo River outlet and the black bar represents an increase in the volcanic activity of the CVL

Full size imageAs expected, given a single marker dataset and uncertainties inherent in the use of secondary calibrations, most nodes on our time tree have 95% HPD values spanning large time intervals, and there is no question that considerable uncertainty persists regarding the precision of the resultant dating scheme. Nonetheless, despite these caveats, our scheme does provide a broad estimate of comparative divergence times among geographically disparate populations of A. spilauchen (Fig. 5). Based on the current analysis, the onset of diversification within the A. spilauchen lineage began during the Middle Miocene (14.8 mya, 95% HPD 8.6–20.7 mya), represented by the split of a west African lineage comprising specimens from Ghana and Guinea. These two lineages subsequently diverged during the late Pliocene (3.5 mya, 95% HPD 0.6–8.7 mya). A split between specimens from Gabon and all the remaining populations occurred during the late Miocene (9.5 mya, 95% HPD 4.8–14.9 mya). This was followed by another in the transition between the late Miocene and the Pliocene (5.6 mya, 95% HPD 2.3–9.5 mya), in which two clades diverged, one including specimens from Nigeria and Equatorial Guinea and the other those from the Kouilou, lower Congo and Angola. Later, the lineage including Nigerian and Equatorial Guinean specimens diverged at the onset of the Pleistocene (2.5 mya, 95% HPD 0.8–5.0 mya). The remaining lineage diversification time estimates are extremely recent ranging from around 1 mya to the near present.
Ancestral area reconstruction (Fig. 6)Fig. 6
S-DIVA Ancestral area reconstructions of A. spilauchen, and input chronogram resultant from BEASTv.1.8 dated analysis. Colours for each designated area are presented in legend box

Full size imageBiogeographic ancestral area reconstruction inferred the current distribution pattern of A. spilauchen lineages to have likely resulted from repeated dispersal and vicariance events (Fig. 6). S-DIVA postulates 6 dispersal, 6 vicariance, and 1 extinction event. The root node, corresponding to the onset of diversification of the A. spilauchen lineage, estimated the areas FGH (Ghana, Nigeria and Equatorial Guinea) and CFG (Guinea, Ghana, and Nigeria), as equally most probable ancestral areas (49% probability). From this root node, a vicariance event is suggested between areas AFH (Gabon, Nigeria, and Equatorial Guinea) and CG (Guinea and Ghana). At the node corresponding to the split between Guinean and Ghanaian haplotypes, the ancestral area CG was recovered (96% probability), and a vicariance event was suggested as the cause of the split between the two areas. The ancestral area AFH was identified for the node in which the Gabon haplotypes split from the remaining haplotypes (95% probability), and it is possible to identify a duplication event (within area speciation) in area A (Gabon) followed by a vicariance event in which one lineage is restricted to Gabon and the other present in area AFH. The area AFH was considered as the ancestral area for the node in which Nigeria and Equatorial Guinea haplotypes split from the Kouilou, lower Congo and Angolan haplotypes (93% probability). Vicariance was recovered as the explanation for the split between areas FH (Nigeria and Equatorial Guinea) and ADE (Gabon, Kouilou, and lower Congo). The ancestral area FH was estimated for the node in which Nigeria and Equatorial Guinea haplotypes split (96% probability), caused by a vicariance event. For the node which corresponds to the split between Kouilou haplotypes and Angola + lower Congo haplotypes, the ancestral area ADE (Gabon, Kouilou, and lower Congo) (93% probability) was estimated, followed by an extinction event in area A (Gabon), a dispersion to area B (Angola) and finally a vicariance event between areas BE (Angola and lower Congo) and D (Kouilou). For the split between Angola and lower Congo haplotypes, the ancestral area BE was delimited (100% probability) and considered to be the result of a vicariance event.
DiscussionPrior to the current study, A. spilauchen had been considered to be widely distributed with a range extending along much of coastal west and west-central Africa. This was based on the assumption that a higher salinity tolerance, relative to that of other procatopodids, would have allowed the species to maintain population connectivity across this extensive geographical range. In addition, an apparent lack of variability in pigmentation patterning between individuals from geographically disparate populations supported a widespread species hypothesis, which in turn resulted in no further investigation of morphological differences between them. Unfortunately, the ongoing COVID-19 pandemic has prevented us from undertaking a morphological investigation to accompany the present study. Loan of museum materials is currently not possible, and we are unable to examine the type specimens of three previously synonymized taxa, A. typus (Ghana), A. bensonii (Liberia) and A. tschiloangensis (Cabinda, Angola), or investigate potential osteological (Parenti, 1981; Ghedotti, 2000; Costa, 2012) or morphometric variation among populations. Further investigation of potential phenotypic differentiation between the molecular lineages identified here is necessary prior to formalizing any taxonomic conclusions, and consequently, we must defer such actions to a future contribution.
The present study has, however, uncovered considerable structuring and genetic divergences between populations that are frequently 4–11 times higher than the traditionally employed sequence divergence heuristic threshold of 2–3% for teleostean conspecifics (e.g. Pereira et al., 2013; Decru et al., 2016; Iyiola et al., 2018; Arroyave et al., 2019) (Fig. 4b, Table 2). Here, we focus our discussion on the potential drivers of diversification and mechanisms that are likely to have shaped the contemporary distributions of lineages within this complex.
The onset of A. spilauchen diversification coincides with one of the main climatic shifts during the Neogene (Fig. 5). Initially, a period known as the Middle Miocene Optimum (between 16 and 14.8 mya) was warm and humid with high precipitation. This was followed by the Middle Miocene Climatic Transition (14.8–12.9 mya) which was much dryer leading to a significant drop in sea levels and increased aridification across the African continent (Flower & Kennett, 1994; Kender et al., 2009, 2014; Herold et al., 2011; Frigola et al., 2018). During the Middle Miocene Optimum, a moist and warm climate promoted the expansion of tropical vegetation, which covered most of the continent expanding even to high latitudes (Lovett, 1993; Maley, 1996; Plana, 2004; Stanley et al., 2005; Frigola et al., 2018). During this time, sea level rise likely engendered mangrove expansion throughout the Atlantic coast, and consequently potential expansion of an ancestral range for A. spilauchen. Our ancestral area analysis estimates an expansion from an area that corresponds to the present-day Ghanaian, Nigerian and Equatorial Guinean coastlines to adjacent Gabon to the south and Guinea to the west (Fig. 6). During the Middle Miocene Climatic Transition, this area experienced a marked contraction of mangrove habitats isolating Aplocheilichthys lineages in the westernmost coastal regions of Guinea and Ghana, and another in Nigeria, Equatorial Guinea and Gabon (Fig. 6).
Studies on the evolution of the Congo River drainage (Beadle, 1981; Burke, 1996; Giresse, 2005; Goudie, 2005; Stankiewicz & de Wit, 2006; Runge, 2007), deposition patterns in the Congo deep sea fan (Lavier et al, 2001; Leturmy et al., 2003; Lucazeau et al., 2003; Anka & Séranne, 2004; Anka et al., 2009; Savoye et al., 2009) and freshwater fish diversification in the basin (Goodier et al., 2011; Schwarzer et al., 2011; Alter et al., 2015, 2017; Arroyave et al., 2020; Stiassny & Alter, in press) reveal a complex geologic history for the most diverse river basin in Africa. In the western basin, sedimentary studies suggest a protracted history of shifting and intermittent outflow of the Congo River into the Atlantic during the Cenozoic. Although a final consensus has yet to be reached, a single high-energy capture event is now generally considered to have established the current Congo outlet to the Atlantic shortly after the Miocene-Pliocene transition. A Pliocene capture (5.3–2.6 mya) is supported by an increase in sediment deposition in the Congo fan and by tectonic activity along the Atlantic Rise during that time (Lavier et al., 2001; Leturmy et al., 2003; Lucazeau et al., 2003; Anka & Séranne, 2004; Anka et al., 2009; Savoye et al., 2009). High humidity during this period is also suggested by palynological data and probably these events facilitated a range expansion from Nigeria, Equatorial Guinea, and Gabon southwards to the regions in and around the newly formed lower Congo estuary at the border between the Democratic Republic of Congo and Angola (Fig. 6). Recent data on the extent of the Congo River plume and its influence on sea surface salinity and temperature over expansive coastal regions (Materia et al., 2012; Denamiel et al., 2013; Chao et al., 2015) highlights the importance of the origin of the present-day Congo River outlet for the expansion of mangroves throughout the region. During wet seasons, the Congo plume connects with the Niger River plume, and a lower salinity is recorded for the entire Gulf of Guinea up to and including the region around the Congo outlet.
West African aridification during the Pliocene (5.3–2.6 mya) is documented by both palynological and sediment data sampled from ocean drilling sites along the coast (Bonnefille et al., 1982; Leroy & Dupont, 1994; Vallé et al., 2017). Study of sedimentological sequences reveals a significant reduction in river discharge and an increase in wind borne grass pollen, both indicative of an arid climate. In addition, a concomitant reduction in mangrove pollen (Rhizophora spp.) suggests that aridification resulted in mangrove reduction and fragmentation. The late Pliocene aridification likely facilitated two vicariance events observed in our study: one between the Ghanaian and Guinean lineages and the other between the Nigerian and Equatorial Guinean lineages. Studies at sites close to Cape Blanc in Mauritania and just south of the mouth of the Senegal River found similar patterns, indicating an onset of aridification around 3.4 mya (Bonnefille et al., 1982; Leroy & Dupont, 1994). A similar study at a site near the Comoé River outlet, identified aridification in north western Africa between 3.5 and 2.9 mya (Vallé et al., 2017), a timing consistent with the proposed date for the split between Ghanaian and Guinean lineages (3.5 mya) estimated in the present study (Fig. 5)).
Other sites with detailed palynological information are near the Niger Delta, where a pronounced aridification with an increase in wind borne grass pollen and marked reduction of Rhizophora pollen is recorded between 2.7 and 2.0 mya (Durugbo et al., 2010; Adeonipekun et al., 2016). These dates are also consistent with the findings of the present study where the split between Nigerian and Equatorial Guinean lineages is estimated to have occurred around 2.5 mya (95% HPD 0.8–5.0 mya) (Fig. 5). Vicariance between Nigerian and Equatorial Guinean lineages may also be related to increased activity of the Cameroon Volcanic Line, a chain of mountains and volcanos that extends from the Cameroonian Highlands to the volcanic islands in the Gulf of Guinea (Deruelle et al., 1991; Marzoli et al., 2000; Burke, 2001). Bioko Island is located about 60 km from the mainland and experienced volcanic activity during the same period with volcanism of Cameroon and Manengouba mounts (around 3.0–1.0 mya) near the coast (Deruelle et al., 1991; Marzoli et al., 2000). Volcanism during low sea level would have had major impacts on water chemistry, temperature and coastal sedimentation directly impacting mangrove cover throughout the region. Recently, a comprehensive study of population connectivity of the mangrove, Rhizophora racemosa, around the Cameroonian and Equatorial Guinean coastline found high levels of genetic structuring related to the volcanic activity of Bioko Island and the Bioko-Cameroon land bridge formation (Ngeve et al., 2016). Here, we suggest that volcanism and the land bridge formation likely also affected A. spilauchen and resulted in the disruption of connectivity (gene flow) between Nigerian and Equatorial Guinean lineages.
The late Pleistocene-Holocene is known for considerable climate instability (Marius & Lucas, 1991; Scourse et al., 2005; Malounguila-Nganga et al., 2017; Maley et al., 2017; Molliex et al., 2019). Although our sampling of A. spilauchen from the southern extent of its range is limited, ancestral area reconstruction posits two additional vicariance events among haplotypes in the Kouilou, lower Congo and Angolan cluster during this timeframe (Fig. 6). Our results indicate a recent divergence and differentiation of the Kouilou haplotypes from the lower Congo and Angolan cluster. However, the low levels of genetic divergence detected, when compared to the significant genetic divergence between the other A. spilauchen populations, suggest the possibility of a continued gene flow between all of these populations (Fig. 4b, Table 2). A recent, and ongoing, connection is suggested by the influence of the Congo River freshwater plume, which is periodically carried south by the Angola current (Kopte et al., 2017), reaching beyond the Nyanga and Kwanza river ouflows (Denamiel et al., 2013). Similarly, an increase in mangrove vegetation persisting since the last deglaciation is evidenced by pollen data from the mouth of Congo (Scourse et al., 2005). Considerably denser population sampling of A. spilauchen throughout this southern region will be necessary to resolve this issue.
ConclusionDespite relatively limited sampling, the applications of species delimitation, phylogeographic, and phylogenetic methods reveal a pattern of genetic differentiation within A. spilauchen that is concordant with a series of historical events recorded since the Middle Miocene. Our study highlights extremely low connectivity between most populations and a time-calibrated phylogeographic pattern that lends support to the novel hypothesis that a major driver of diversification within the lineage has been the shifting dynamics of coastal mangrove forest cover over time. We report, for the first time, a pattern of diversification within a lineage of brackish water fish that is concordant with the historical distribution of coastal mangroves forests, the predominant brackish water habitat of the focal species throughout its range.
From a conservation perspective, these results are of considerable significance since many brackish environments, particularly the mangrove forests, are highly threatened by coastal development and the exploration and extraction of hydrocarbons along the African Atlantic coastline (Alongi, 2015; Feka & Morrison, 2017). It has been estimated that mangroves are disappearing at a rate of 1–2% per year, suggesting the complete disappearance of these societally and biologically important ecosystems within the century (Alongi, 2015). The unexpected diversity observed in the A. spilauchen complex suggests that many of the other taxa that share a similar distribution associated with the same dynamic mangrove habitats may hide a significant, but currently undocumented, diversity under threat. Before formal taxonomic and nomenclatural changes can be undertaken, morphological analyses of the distinct populations (OTUs) identified herein are needed, and conservation assessments for each are critical as many of these potential new species are likely highly threatened by ongoing coastal development throughout the region.
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AcknowledgmentsOur thanks to J. Snoeks and M. Parrent (RMCA), T. Vigliotta, R. Arrindell and C. Lewis (AMNH), W. Costa (UFRJ), B. Sidlauskas and P. Konstantinidis (OS), J. Williams and D. Pitassy (USNM), I. Okyere (University of Cape Coast, Ghana), J. Cutler (University of California, Santa Cruz, USA) and J. Hervé Mve Beh (Libreville, Gabon) for the donation or loan of specimens and tissue samples. We thank A. Katz (UFRJ) R. Bills (SAIAB) and K. Bernotas (AMNH) for photographing preserved specimens, and C. Aubin (Périgueux, France), L. Chirio (Brazzaville, Republic of the Congo), L. Kent (Seattle, USA), P. Venstermans (Zwijndrecht, Belgium), and R.B. Tate (Witrivier, South Africa) for providing pictures of live specimens. We gratefully acknowledge P. Amorim and J. Mattos (UFRJ) and T. Ntokoane (SAIAB) for assistance in the Molecular Laboratory, and for the use of equipment provided by the UFRJ Ichthyology Laboratory and the NRF-SAIAB Molecular Genetic Laboratory. Partial funding for this project was provided by the National Geographic Society (#WW-055R-17) and Randolph-Macon College, and the Axelrod Curatorship of the American Museum of Natural History.
Author informationAffiliations

South African Institute for Aquatic Biodiversity, Private Bag 1015, Grahamstown, 6140, South Africa
P. H. N. Bragança & A. Chakona
Department of Ichthyology and Fisheries Science, Rhodes University, P.O. Box 94, Grahamstown, 6140, South Africa
A. Chakona
Section of Vertebrates, Ichthyology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080, Tervuren, Belgium
J. Van der Zee
Biology Department, Randolph-Macon College, Ashland, VA, 23005, USA
R. C. Schmidt
Division of Fishes, Smithsonian Research Associate, National Museum of Natural History, Washington, DC, 20560, USA
R. C. Schmidt
Department of Ichthyology, American Museum of Natural History, Central Park West at 79th Street, New York, NY, 10024, USA
M. L. J. Stiassny

ContributionsAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by P. Bragança and R. Schmidt. Figures were prepared by M. Stiassny and P. Bragança. The first draft of the manuscript was written by P. Bragança, and all authors commented and provided changes on previous versions of the manuscript. All authors read and approved the final manuscript.
Corresponding authorCorrespondence to P. H. N. Bragança.
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Handling editor: Christian Sturmbauer
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About this articleCite this articleBragança, P.H.N., Van der Zee, J., Chakona, A. et al. Following the Mangroves: diversification in the banded lampeye Aplocheilichthys spilauchen (Duméril, 1861) (Cyprinodontiformes: Procatopodidae) along the Atlantic coast of Africa. Hydrobiologia (2021). https://doi.org/10.1007/s10750-020-04497-3
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Received19 September 2020
Revised28 November 2020
Accepted15 December 2020
Published03 January 2021
DOIhttps://doi.org/10.1007/s10750-020-04497-3

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Keywords

Brackish water killifish
Mangrove dynamics
Miocene climatic shift
Species delimitation

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Systematics and Taxonomy of Chapalichthys (Cyprinodontiformes:
Goodeidae), a Small Genus of Live-Bearers from Central Mexico
Kyle R. Piller1, Devin D. Bloom2, John Lyons3, and Norman Mercado-Silva4
Kyle R. Piller1, Devin D. Bloom2, John Lyons3, and Norman Mercado-Silva4

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Nemipterus elaine • A New Species of Nemipterus (Pisces: Nemipteridae) from the Western Indian Ocean

Nemipterus elaine
Russell & Gouws, 2020

DOI: 10.11646/zootaxa.4895.4.7

Abstract
A new species of threadfin bream, Nemipterus elaine, from the Western Indian Ocean is described. The new species is known so far only from off the coast of southern Mozambique, and appears most closely related morphologically and genetically to N. randalli Russell, 1986, but differs in having shorter pectoral and pelvic fins, and the upper caudal lobe produced to form a short, bright yellow filament (a long red trailing filament present in N. randalli). A key to the species of Nemipterus in the Western Indian Ocean is provided.

Keywords: Pisces, Nemipteridae, Nemipterus elaine n.sp., Mozambique, Western Indian Ocean

Nemipterus elaine

Barry C. Russell and Gavin Gouws. 2020. A New Species of Nemipterus (Pisces: Nemipteridae) from the Western Indian Ocean. Zootaxa. 4895(4); 573–580. DOI: 10.11646/zootaxa.4895.4.7

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Channa aristonei a new species

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UK Government papers relating to Import & export of Ornamental fishes can be found at:- www.gov.uk/government/publications/fish-health-certificates
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Catfishes of the Genus Sperata (Pisces: Bagridae) in India

Sperata in India

in Kumar, Charan, Krishnaprasoon & Basheer, 2020.
DOI: 10.1111/jfb.14590
  facebook.com/meenkaran

Abstract
DNA barcode data of the South Asian bagrid catfish genus Sperata indicate the presence of at least five species in the Indian subcontinent. Those results, which are supported by morphological data, show a marked increase in species diversity from the recent taxonomic and fishery literature, although each of the five species had been previously named. Two species are restricted to rivers of peninsular India south of the Godavari: Sperata aorides from the Cauvery river basin and S. seenghala from the Krishna river basin. Most literature records of S. seenghala from the Ganges‐Brahmaputra‐Meghna river basins likely refer to S. lamarrii, a species which appears to also be present in the Indus river basin. Some genetic data reported as S. seenghala from the Ganges‐Brahmaputra‐Meghna river basins refer to S. aorella. S. aor is widespread in the Ganges‐Brahmaputra‐Surma river basins in India and Bangladesh, extending southwards to the Godavari river.

Keywords: Cauvery, fisheries, Ganges, ichthyology, Krishna, taxonomy, zoogeography



Sperata aorides (Jerdon)

Sperata lamarrii (Valenciennes)

Sperata seenghala (Sykes)

Sperata aor (Hamilton)

Sperata aorella (Blyth)

CONCLUSION:
The results of our investigation suggest there are at least five valid species of Sperata in the Indian subcontinent. S. aorides is endemic to the Cauvery river basin and S. seenghala is probably endemic to the Krishna river basin. Records of S. seenghala from the Ganges‐Brahmaputra‐Meghna river basins likely refer to S. lamarrii, a species which appears to also be present in the Indus river basin. Additionally, some reports of S. seenghala from the Ganges‐Brahmaputra‐Meghna river basins definitely refer to S. aorella. Neither S. lamarrii nor S. aor appear to be present in peninsular India south of the Godavari, and investigations into reports of S. aor and S. seenghala from river basins removed from their original descriptions may yield additional species. Proper taxonomic identification of species within the genus is critical given the importance of this genus to fisheries and attempts to introduce them to aquaculture.

Rahul Girish Kumar, Ravi Charan, Nadumury Pradeep Krishnaprasoon and Valaparambil Saidumohammad Basheer. 2020. Catfishes of the Genus Sperata (Pisces: Bagridae) in India.
Journal of Fish Biology. DOI: 10.1111/jfb.14590
facebook.com/meenkaran/posts/3466219466827064

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Microcambeva bendego • A New Catfish Species of Microcambeva Costa & Bockmann 1994 (Siluriformes: Trichomycteridae) from A Coastal Basin in Rio de Janeiro State, southeastern Brazil

Microcambeva bendego
de Medeiros, Moreira, de Pinna & Lima, 2020

DOI: 10.11646/zootaxa.4895.1.6

Abstract
Microcambeva bendego, a small psammophilous catfish species, is described from the rio Guapi-Macacu basin at Guanabara Bay in Rio de Janeiro State, an Atlantic Forest remnant. This coastal drainage has been explored by several naturalists and fish researchers since the 19th century. It is a drainage with remarkably high endemism and species richness, and some recently-described and threatened species. The new species is distinguished from all congeners by two distinctive characters: long finger-like projections in the branchial isthmus and a large opercular patch of odontodes with 19 odontodes. Due to the paucity of specimens (n=3) osteological features of the new species were accessed by CT-Scan images of the holotype. Microcambeva bendego shares putative synapomorphies with two congeners, M. ribeirae and M. filamentosa, such as the fusion of supraorbital pore s6, the absence of ossification in the anterior autopalatine cartilage, the presence of an elongated and wide posterior process of the autopalatine, and a concavity on the dorsal process of the opercle. Those characters suggest that M. bendego is more closely related to those two species from the rio Ribeira de Iguape basin than to other congeners. The biogeography and conservation status of M. bendego are also discussed.

Keywords: Pisces, Taxonomy, Microcambevinae, Fluminense ecoregion, Atlantic Forest, Guanabara bay, CT-Scan

Figure 1. Microcambeva bendego, new species, holotype, MNRJ 52042, 28.1 mm SL.
Rio Guapiaçu, near Cachoeiras de Macacu, rio Guapi-Macacu basin, Guapimirim Municipality, Rio de Janeiro State, southeastern Brazil.
a. lateral view; b. dorsal view; c. ventral view. Scale: 10 mm.

Lucas Silva de Medeiros, Cristiano Rangel Moreira, Mario de Pinna and Sergio M. Q. Lima. 2020. A New Catfish Species of Microcambeva Costa & Bockmann 1994 (Siluriformes: Trichomycteridae) from A Coastal Basin in Rio de Janeiro State, southeastern Brazil. Zootaxa. 4895(1); 111–123. DOI: 10.11646/zootaxa.4895.1.6
Researchgate.net/publication/346988544_A_new_catfish_species_of_Microcambeva_from_a_coastal_basin_in_Rio_de_Janeiro_State_sout
heastern_Brazil

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Species Delimitation Reveals An Underestimated Diversity of Andean Catfishes of the Family Astroblepidae (Teleostei: Siluriformes)

A. Astroblepus ardiladuartei, B. A. cachara,
C. A. caquetae, D. A. curitiensis,
E. A. homodon, F. A. gr. grixalvii,
G. A. itae, H. A. latidens, I. A. onzagaensis, J. A. pradai.

in Ochoa, Melo, García-Melo, et al., 2020.
DOI: 10.1590/1982-0224-2020-0048

Catfishes of the family Astroblepidae form a group composed by 82 valid species of the genus Astroblepus inhabiting high-gradient streams and rivers throughout tropical portions of the Andean Cordillera. Little has been advanced in the systematics and biodiversity of astroblepids other than an unpublished thesis, a single regional multilocus study and isolated species descriptions. Here, we examined 208 specimens of Astroblepus that apparently belong to 16 valid species from several piedmont rivers from northern Colombia to southern Peru. Using three single-locus approaches for species delimitation in combination with a species tree analysis estimated from three mitochondrial genes, we identified a total of 25 well-delimited lineages including eight valid and 17 potential undescribed species distributed in two monophyletic groups: the Central Andes Clade, which contains 14 lineages from piedmont rivers of the Peruvian Amazon, and the Northern Andes Clade with 11 lineages from trans- and cis-Andean rivers of Colombia and Ecuador, including the Orinoco, Amazon, and Magdalena-Cauca basins and Pacific coastal drainages. Results of species delimitation methods highlight several taxonomical incongruences in recently described species denoting potential synonymies.

Keywords: Andes, Catfishes, Delimitation, Ostariophysi, Systematics, Taxonomy.

Species of Astroblepus included in this study,
A. A. ardiladuartei (LBP 26696 topotype live, 4.54 mm SL), B. A. cachara (LBP 26712 topotype live, 4.23 mm SL), C. A. caquetae (CZUT-IC 18464 topotype of museum, 7.84 mm SL), D. A. curitiensis (LBP 97118 topotype live, 5.92 mm SL),
E. A. homodon (CZUT-IC 18390, 6.15 mm SL), F. A. gr. grixalvii (LBP24242 topotype live, 11.70 mm SL); F’. A. gr. grixalvii (CZUT-IC 18498 specimen of Magdalena basin 6,01 mm SL); F”. A. gr. grixalvii (CZUT-IC 18320 specimen of Cauca basin, 15.25 mm SL),
G. A. itae (topotype live, 3.58 mm SL), H. A. latidens (topotype live, 13.40 mm SL), I. A. onzagaensis (topotype live, 7.82 mm SL), J. A. pradai (topotype live, 4.53 mm SL),
K. A. trifasciatus (topotype of museum, 9.65 mm SL), K’. A. trifasciatus (topotype of museum, 9.01 mm SL), L. A. aff. trifasciatus (specimen of Magdalena basin, 7.94 mm SL), M. A. verai (topotype live, 3.51 mm SL).

Luz E. Ochoa, Bruno F. Melo, Jorge E. García-Melo, Javier A. Maldonado-Ocampo, Camila S. Souza, Juan G. Albornoz-Garzón, Cristhian C. Conde-Saldaña, Francisco Villa-Navarro, Armando Ortega-Lara and Claudio Oliveira. 2020. Species Delimitation Reveals An Underestimated Diversity of Andean Catfishes of the Family Astroblepidae (Teleostei: Siluriformes). Neotropical Ichthyology. 18(4), e200048. DOI: 10.1590/1982-0224-2020-0048

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Betta nuluhon, a new species of fighting fish from western Sabah, Malaysia (Teleostei: Osphronemidae)
N. S. S. KAMAL, H. H. TAN, CASEY K. C. NG
Abstract
Betta nuluhon, new species, is described from a hill stream habitat in western Sabah. This species is allied to both B. chini and B. balunga, and differs from rest of its congeners in the B. akarensis group in having the following combination of characters: yellow iris when live; mature males with greenish-blue iridescence on opercle when live; mature fish with distinct transverse bars on caudal fin; slender body (body depth 22.1–25.2 % SL); belly area with faint reticulate pattern (scales posteriorly rimmed with black); absence of tiny black spots on anal fin; lateral scales 29–31 (mode 30); predorsal scales 20–21 (mode 20). Notes on a fresh series of B. chini are also provided.

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Ichthyological Exploration of Freshwaters, Volume 30 (2020)May 14, 2020 / 0 Comments / in Biology IEF IEF… Black-and-white figures, 13 tables PDF Stauffer, Jay R., Jr .: Description of three species of Salvelinus (Teleostei: Salmonidae) from the Great Smoky Mountains National Park, Tennessee, USA 97-110 PDF Yoğurtçuoğlu, Baran, .

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A new species of Corcyrogobius (Teleostei: Gobiidae) from Île de Ngor, Senegal

MARCELO KOVAČIĆ, PETER WIRTZ, ULRICH K. SCHLIEWEN
Abstract
Corcyrogobius pulcher sp. nov. is described from off Île de Ngor, Dakar, Senegal. Corcyrogobius pulcher is distinguished from its two congeners by having the rear edge of the jaws ending posteriorly below mideye, second dorsal fin I/9, pectoral fin rays 17, pelvic fins oval or truncated posteriorly, scales in lateral series 26–27, anterior oculoscapular head canal with pore β, suborbital row b of sensory papillae anteriorly beginning below vertical of posterior edge of eye, dark vertical caudal bar, branchiostegal membrane without intense dark spot, cheek with two oblique whitish stripes, the first going from the eye downwards and forward to the posterior jaws, the second on the preopercular, alternating with brown oblique stripe going from behind the eye downwards and forward across the cheek. Furthermore, mitochondrial COI-barcoding data unambiguously support the species-level distinctiveness of the three Corcyrogobius species. A key to the species of Corcyrogobius is provided.

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A journey through the Amazon Middle Earth reveals Aspidoras azaghal (Siluriformes: Callichthyidae), a new species of armoured catfish from the rio Xingu basin, BrazilLuiz F. C. Tencatt

Janice Muriel‐Cunha

Jansen Zuanon

Marlon F. C. Ferreira

Marcelo R. Britto
First published: 16 July 2020

https://doi.org/10.1111/jfb.14467urn:lsid:zoobank.org:pub:3F4FA7A5‐4F55‐4068‐9616‐67777E75C173
Funding information: Conselho Nacional de Desenvolvimento Científico e Tecnológico (LFCT: processes #141061/2014‐6 and #304997/2016‐1; MRB: process #309285/2018‐6; JZ: process #313183/2014‐7); Fundação Amazônia de Amparo a Estudos e Pesquisas (process #184/2009); Edital Programa Institucional de Pesquisa nos Acervos da USP and Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Grant Number: 200.103/2019; PhD project of LFCT; Programa de Bolsa de Iniciação Científica (PIBIC/UFPA) of MFCF

AbstractAspidoras azaghal n. sp. was discovered during a multitaxonomic scientific expedition to the remote Amazon Terra do Meio region in tributaries to the rio Xingu basin, Pará, Brazil. The new species can be promptly distinguished from its congeners by the following combination of features: (a) absence of the first dorsal‐fin element; (b) parieto‐supraoccipital fontanel located medially on bone; (c) absence of a longitudinal dark‐brown or black stripe along flank midline; (d) ventral surface of trunk covered by clearly smaller, irregular and/or roundish platelets; (e) inner laminar expansion of infraorbital 1 well developed; (f) relatively wide frontal bone, with width equal to half of entire length; (g) absence of a thick, longitudinal conspicuous dark‐brown stripe along dorsal portion of flank; and (h) poorly developed serrations on posterior margin of the pectoral‐fin spine. Besides morphological evidence, the molecular analyses indicated significant differences between the new species and its congeners, with A. albater and A. raimundi as its closest species, showing 6.53% of genetic differentiation in both cases. The intraspecific molecular data revealed gene flow (peer fixation index, FST = 0.05249, P > 0.05, for the cytochrome oxidase I (COI) marker and FST = ‐0.01466, P > 0.05, for the control region) between specimens upstream and downstream from a 30‐m height waterfall at the type‐locality, which therefore represent a single population. Furthermore, it was possible to observe a unidirectional gene flow pattern, with genetic diversity increasing in the downstream direction.

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Upeneus floros, a new goatfish from South Africa and Mozambique, with updated taxonomic accounts for U. guttatus and U. pori and a key to Western Indian Ocean Upeneus species (Mullidae)
FRANZ UIBLEIN, GAVIN GOUWS, MARK LISHER, BERNARDINO S. MALAUENE
Abstract
The highly diverse goatfish genus Upeneus (Mullidae) requires enhanced attention regarding the possible occurrence of undescribed species in insufficiently explored regions. This study focuses on the South-Western Indian Ocean region (SWIO), and on the so-called japonicus-group, a taxonomic species group of Upeneus. Based on in-situ observations and collections in Sodwana Bay, KwaZulu-Natal, South Africa, the Floros goatfish, U. floros n. sp., is described. Detailed comparative studies of colour patterns and morphological characters of all other 13 japonicus-group species were undertaken as well as COI barcoding. The new species occurs in the coastal area between Angoche, N Mozambique and KwaZulu-Natal and partly overlaps in distribution with two similar species, U. guttatus, widely distributed in the Indo-W Pacific, and U. saiab, assumed to be endemic in a small area off Angoche. Two additional japonicus-group species occurring in the SWIO, U. seychellensis from the Seychelles Bank and U. pori from the Mediterranean Sea (as Lessepsian migrant), Northern Red Sea and Madagascar, were also compared. Because specimens as well as in-situ photographs of U. floros have been erroneously identified as either U. guttatus or U. pori during previous studies, updated taxonomic accounts and diagnoses are provided for these species taking size-related and population differences into account. For U. pori, of which a single preserved specimen from SW Madagascar was known so far, a new record from NE Madagascar is reported based on three specimens and a fresh-colour photo. Upeneus floros can be distinguished from U. guttatus and U. pori by a combination of three characters: head length, first dorsal-fin height and number of gill rakers. Upeneus guttatus can be distinguished from the other two species by disproportionally higher anterior dorsal-fin spines vs. a proportional decrease of dorsal-fin spines in height, barbels mostly yellow vs. white or creamy-white, and slightly fewer pectoral-fin rays. COI barcoding detected a clear distinction between U. guttatus and U. floros and U. pori, respectively, but no significant divergence between the two latter species. COI barcoding also failed to differentiate several other Upeneus species which are clearly distinguished morphologically. Possible interrelationships between species distribution patterns and physical oceanography are discussed. An identification key for the 22 WIO Upeneus species is provided.

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A new rheophilic South American darter (Crenuchidae: Characidium) from the rio Juruena basin, Brazil, with comments on morphological adaptations to life in fast‐flowing watersAngela M. Zanata

Willian M. Ohara

Osvaldo T. Oyakawa

Fernando C. P. Dagosta
First published: 06 August 2020

https://doi.org/10.1111/jfb.14485Funding information: South American Characiformes Inventory, Grant/Award Number: FAPESP 2011/50282‐7; Diversidade e Evolução de Gymnotiformes (Teleostei, Ostariophysi), Grant/Award Number: 2016/19075‐9; FAPESP, Grant/Award Number: 2017/09321‐5; Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq, Grant/Award Number: 309993/2016‐4; FAPESP, Grant/Award Number: 2013/22473‐8; FAPESP 2016/07246‐3 and by – CNPq, Grant/Award Number: 405643/2018‐7

AbstractCharacidium iaquira, a new species from the upper rio Juruena, rio Tapajós basin, Brazil, is described. The new species can be promptly distinguished from all congeners by having a unique v‐shaped dark mark lying along the caudal‐fin extension, in medium‐ and large‐sized specimens, and a remarkable iridescent green colouration in life. Characidium iaquira is closely related to Characidium crandellii and Characidium declivirostre by sharing unambiguous synapomorphies such as branchiostegal membranes united to each other across the isthmus, a scaleless area extending from the isthmus to the pectoral girdle, and dermal flaps surrounding anterior and posterior naris independent, but touching each other distally. Morphological specializations of the paired fins in the three riffle‐dwellers species are discussed, including the wing‐like shape, robustness, and inclination of the pectoral fin.

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Lepadichthys conwayi • A New Species of Lepadichthys (Teleostei, Gobiesocidae) from the Central South Pacific and Comments on the Taxonomic Status of Lepadichthys springeri Briggs, 2001

Lepadichthys conwayi
Fujiwara & Motomura, 2020

DOI: 10.1643/CI2020036

Abstract
Lepadichthys conwayi, new species, is described on the basis of 42 specimens (13.0–42.0 mm in standard length [SL]) collected from the central South Pacific and characterized by the following combination of characters: head sensory canal pores well developed, including 2 nasal, lacrimal and postorbital, and 3 preopercular pores; 13–16 (modally 15, rarely 16) dorsal-fin rays; 11–14 (12, rarely 14) anal-fin rays; 27–30 (28) pectoral-fin rays; 8 or 9 (9), 8–11 (9), and 8–11 (9) gill rakers on first to third arches, respectively; upper end of gill membrane level with base of 7th to 10th (usually 9th) pectoral-fin ray in lateral view; disc length and width 15.0–17.1 (mean 16.0) and 11.1–16.1 (13.9) % SL, respectively, disc length plus disc width 27.8–33.2 (30.0) % SL; dorsal and anal fins with very weak membranous connections to (rarely separated from) caudal fin, posteriormost points of membranes usually just short of or just reaching vertical through caudal-fin base, otherwise very slightly beyond fin base; dorsal- and anal-caudal membrane lengths 3.4–7.1 (4.8) and 3.0–6.0 (4.8) % of caudal-fin length, respectively; black stripe on snout tip through eye to posterior region of head. In addition, examination of the type specimens of Lepadichthys springeri Briggs, 2001 revealed them to be conspecific with L. misakius (Tanaka, 1908), a valid species recently resurrected from the synonymy of L. frenatus Waite, 1904. Accordingly, L. springeri is regarded as a junior synonym of L. misakius.

Fresh coloration of Lepadichthys conwayi, new species.
(A) USNM 423325, holotype, 39.3 mm SL, Raivavae Island, Austral Islands;
(B) USNM 404728, paratype, 33.2 mm SL, Totegegie Island, Gambier Islands;
(C) USNM 422862, paratype, 26.4 mm SL, same as holotype;
(D) USNM 423420, paratype, 37.8 mm SL, Tubuai Island, Austral Islands;
(E) USNM 423414, paratype, 31.3 mm SL, same as USNM 423420.
(A–C) Lateral views. (D) Dorsal view. (E) Ventral view.
Photos by J. Williams.

Lepadichthys conwayi, new species
Conway’s Clingfish

Distribution.--Currently known only from the Cook Islands, the Austral and Gambier Islands (French Polynesia), and Pitcairn Islands in the central South Pacific (Fig. 8).

Etymology.--The specific name conwayi is in recognition of Dr. Kevin Conway for his recent contributions to the systematics of clingfishes. The name is used as a noun in the genitive case.

Kyoji Fujiwara and Hiroyuki Motomura. 2020. A New Species of Lepadichthys from the Central South Pacific and Comments on the Taxonomic Status of Lepadichthys springeri Briggs, 2001 (Gobiesocidae). Copeia. 108(4); 833-846. DOI: 10.1643/CI2020036.

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A new livebearing fish of the genus Limia (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, HaitiRodet Rodriguez‐Silva

Pablo F. Weaver
First published: 29 February 2020

https://doi.org/10.1111/jfb.14301Funding information: Financial support was given by a University of La Verne Faculty Research Grant, a University of Colorado Boulder Museum Research Grant, and a University of Colorado Boulder Department of Ecology and Evolutionary Biology departmental graduate student grant. The Caribaea Initiative and the National Geographic Society (WW‐054R‐17) provided additional funding for this research.

AbstractLimia islai, a new species of livebearing fish, is described from Lake Miragoane in south‐western Haiti on Hispaniola. The new species has a conspicuous barred pattern consisting of several (4–12) black bars along the body, ray 4p serrae of the gonopodium in males with 10 segments and origin of dorsal fin in females slightly behind the origin of the anal fin. Although the new species colour pattern is similar to that of the humpbacked limia Limia nigrofasciata Regan 1913, L. islai sp. nov. has exclusive morphological features, such as slender body, lack of hump anterior to dorsal fin in males and presence of specific features in the gonopodial suspensory, which allow an unambiguous diagnosis from L. nigrofasciata. L. islai further differs from L. nigrofasciata in reproductive behaviour since L. islai males rely on sneak copulations and gonopodial thrusting, whereas L. nigrofasciata display an elaborate courtship behaviour. The new species is also genetically distinct in both nuclear (Rh, Myh6) and mitochondrial (12S, ND2, D‐loop, Cytb) genes from other species in the genus showing reciprocal monophyly. The description of this new Limia species from Lake Miragoane confirms this lake as an important centre of endemism for the genus, with a total of eight endemic species described so far.

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Rhinogobius houheensis, a new species of freshwater goby (Teleostei: Gobiidae) from the Houhe National Nature Reserve, Hubei province, China

KUNYUAN WANGHE, FAXIANG HU, MINHAO CHEN, XIAOFENG LUAN
Abstract
A new freshwater goby, Rhinogobius houheensis, is described based on 40 specimens in a freshwater stream from the Houhe National Nature Reserve, Hubei Province, China. The new species can be distinguished from all its congeneric species by the following combination of characters: thee first dorsal fin rays VI, the second dorsal fin rays I/9-I/10; anal fin rays I/7-I/8; pectoral-fin rays 16–17; longitudinal scale series 37–40; transverse scales 12–14; predorsal scale series 0; and vertebrae counts 12+18=30. The first three spinous rays in the first dorsal fin are colored with two dark-blue stripes and one black spot in alive.

Keywords
fish taxonomy, high vertebrae counts, valid species, Yangtze River, Pisces

Full Text:
PDF/A (7MB)

DOI: https://doi.org/10.11646/zootaxa.4820.2.8

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A new endangered species of Megaleporinus (Characiformes: Anostomidae) from the Rio de Contas basin, eastern Brazil

José L. O. Birindelli

Heraldo A. Britski

Jorge L. Ramirez
First published: 24 February 2020

https://doi.org/10.1111/jfb.14299
Citations: 1Funding information: This study was funded by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP, process10/512150–9), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, processes 420255/2016‐8, 302872/2018‐3). Specimens were collected in expeditions funded by FAPESP (process 2011/50282‐7), and Fundação Araucária (FA, process 177/2014).

AbstractA new species of Megaleporinus is described from the Rio de Contas, a coastal drainage of eastern Brazil, and its phylogenetic relationships are studied using molecular data. The new species is unique among Anostomidae by possessing two exclusive features: an irregular dark longitudinal stripe from supracleithrum to second midlateral blotch and anterior cranial fontanel partially closed. In addition, the new species is diagnosed by having three premaxillary teeth, three dentary teeth, 37 or 38 scales in lateral line, 16 scale rows around caudal peduncle, three dark midlateral blotches on body, and red fins in life. The new species is closely related to M. obtusidens from the São Francisco basin, corroborating previous studies that indicated that the latter represents a species complex as currently defined. The new species exhibits the first rib enlarged in mature males, a feature described for some congeners. The new species is herein considered to be Endangered under the IUCN criteria.

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Vanderhorstia vandersteene, a new species of shrimpgoby (Pisces: Gobiidae) from Papua New Guinea
Allen, Gerald R.; Erdmann, Mark V.; Brooks, William D.

A new species of gobiid fish, Vanderhorstia vandersteene, is described from the East Cape region of Milne Bay Province, Papua New Guinea on the basis of five specimens 17.5–32.2 mm SL. Diagnostic features include dorsal-fin elements VI-I,10–12; the fourth dorsal-fin spine filamentous, reaching the base of about the fifth to seventh segmented dorsal-fin ray when adpressed; anal-fin rays I,11; pectoral-fin rays 16–18; lateral scales 35–37; transverse scales 10; body scales mostly ctenoid, except cycloid scales anterior to the level of about the second-dorsal-fin origin, as well as on the pectoral-fin base, prepelvic region, and the lower side between the pectoral-fins and pelvic fins; scales absent on the head, including medially and anteriorly on the predorsal region; the caudal fin lanceolate with an elongate, median filament; color in life light neon blue with a wavy yellow-orange stripe from the upper operculum to the upper caudal-fin base, prominent yellow-orange bars, bands, and spots on the head and upper sides, a pair of yellow stripes on the second dorsal fin, and yellow streaks and bands on the caudal fin. We include a key to the Vanderhorstia species with low lateral-scale counts (less than 45).

https://zenodo.org/record/3959464#.X9PtgNhKjIU

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Phenacorhamdia roxoi • A New Species of Phenacorhamdia Dahl 1961 (Siluriformes: Heptapteridae) from the Paranapanema River Basin, southeastern Brazil

Phenacorhamdia roxoi
Silva, 2020

DOI: 10.11646/zootaxa.4890.2.8

Abstract
A new species of Phenacorhamdia is described from Paranapanema River, Upper Paraná River basin, southeastern Brazil. The new species is distinguished from congeners by the combination of following characters 45−46 vertebrae; an entirely dark-brown body; nine pleural ribs; eight branched rays in upper lobe of caudal fin; seven branched rays in pectoral fin; 13 anal-fin rays with 9−10 branched; first basal radial inserted at the 13th vertebrae and eight branchiostegal rays.
Keywords: Siluriformes, Catfishes, Neotropical freshwaters fishes, Taxonomy, Upper Paraná River basin

Gabriel S. C. Silva. 2020. A New Species of Phenacorhamdia Dahl 1961 (Siluriformes: Heptapteridae) from the Paranapanema River Basin, southeastern Brazil. Zootaxa. 4890(2); 275–282. DOI: 10.11646/zootaxa.4890.2.8

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Indoreonectes telanganaensis • A New Species of Loach (Teleostei: Nemacheilidae) from the Godavari Basin of India

Indoreonectes telanganaensis

Prasad, C. Srinivasulu, A. Srinivasulu, Anoop & Dahanukar, 2020
DOI: 10.11646/zootaxa.4878.2.7
facebook.com/kpanatheist

Abstract
A new species of hill-stream loach, Indoreonectes telanganaensis, is described from a seasonal tributary of the Godavari River at Maisamma Loddi, within the Kawal Tiger Reserve, Telangana State, India. The new species is distinguished from its congeners by a combination of characters including caudal peduncle as long as deep; eye large, its diameter about one-fifth head length; pectoral fin as long as head; nasal barbel reaching the middle of the eye; dorsal-fin origin on vertical through pelvic-fin origin; and bars on the lateral side of the body well defined and wide. We also provide multivariate morphometric, and DNA analysis based on the mitochondrial cytochrome b gene sequence to support the distinction of the new species.

Keywords: Telangana loach, hillstream loach, molecular phylogeny, Telangana State, Pisces

Kante Krishna Prasad, Chelmala Srinivasulu, Aditya Srinivasulu, V. K. Anoop and Neelesh Dahanukar. 2020. Indoreonectes telanganaensis, A New Species of Loach (Teleostei: Nemacheilidae) from the Godavari Basin of India. Zootaxa. 4878(2); 335–348. DOI: 10.11646/zootaxa.4878.2.7
facebook.com/kpanatheist/posts/3621160851274985

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Riddle on the Riffle: Miocene Diversification and Biogeography of Endemic Mountain Loaches (Cypriniformes: Balitoridae: Bhavania) in the Western Ghats Biodiversity Hotspot

Bhavania australis  (Jerdon, 1849)
The mountain loach, Bhavania australis is a ‘cryptic species complex’ endemic to the Western Ghats Biodiversity Hotspot in India.

in Sidharthan, Raghavan, Anoop, et al., 2020.
DOI: 10.1111/jbi.13972
twitter.com/JBiogeography
Photo: Beta Mahatvaraj  twitter.com/LabRajeev

Abstract
Aim: The Western Ghats Hotspot in peninsular India harbours remarkable diversity and endemism of freshwater fish. However, the ichthyofauna's evolutionary histories and biogeography are poorly known. Here, we investigate (a) the diversity, evolutionary history and biogeography of endemic mountain loaches and (b) the potential influence of the physiography of hill ranges, geological barriers and river systems on the diversification and cladogenesis of loaches, in the Western Ghats Biodiversity Hotspot.

Location: Southern Western Ghats mountain ranges (8–13°N latitudes), Western Ghats‐Sri Lanka Biodiversity Hotspot.

Taxa: Mountain loaches Bhavania annandalei and B. australis (Cypriniformes: Balitoridae).

Methods: We carried out a multigene phylogenetic analysis with mitochondrial and nuclear markers using Bhavania specimens collected throughout the genus' range. The Automated Barcode Gap Analysis, Poisson Tree Process and Generalized Mixed Yule‐Coalescent Model were used to delimit species. A Bayesian chronogram was constructed to estimate the time elapsed since the most recent common ancestor of the distinct lineages of Bhavania. Ancestral ranges of distinct lineages of Bhavania were reconstructed using the dispersal–extinction–cladogenesis model.

Results:
Phylogenetic analysis of combined mitochondrial and nuclear data, as well species delimitation using the Poisson Tree Process and Generalized Mixed Yule‐Coalescent Model analyses supported eight distinct lineages, which included the narrowly distributed B. annandalei and widely distributed B. australis. The Barcode Gap Analysis, however, supported only seven lineages. Bayesian divergence time dating suggests that the genus originated early in the Neogene and diversified in the Miocene. Ancestral state reconstruction indicated Bhavania diversifed as a result of sympatric, subset and vicariant speciation with five dispersal and one vicariant events across biogeographic barriers and river systems.

Main conclusions:
Bhavania australis is a ‘species complex’. Miocene‐associated climatic changes including intensification of the south‐west monsoon likely triggered dispersal and range expansion; subsequent aridification would have led to drying up of riverine connections, formation of land barriers and fragmentation of streams, resulting in cladogenesis. Our results also provide preliminary evidence that Cauvery, one of the largest east flowing rivers of Western Ghats, facilitates an east‐west pathway for dispersal and diversification of endemic lineages of the region.

Keywords: Bhavania, biogeographical barriers, cryptic species, dispersal vicariance

in Sidharthan, Raghavan, Anoop, et al., 2020.
DOI: 10.1111/jbi.13972
twitter.com/JBiogeography

CONCLUDING REMARKS
Our multi‐locus phylogeny and divergence time dating suggest that the endemic WG mountain loach genus Bhavania originated in the early Neogene, and diversified/radiated into cryptic lineages in the Miocene. Facilitated by Miocene‐associated climatic changes including intensification of the monsoonal rains, Bhavania dispersed across the WG, expanding their range. Cladogenesis events were subsequently triggered by aridification and drying up of riverine connections, formation of land barriers and fragmentation of streams. Our results also provide the first evidence for Cauvery, one of the largest east flowing rivers of Western Ghats, facilitating an east–west pathway for dispersal and diversification of endemic lineages of the region. As a next step, a comprehensive family‐wide phylogeny of balitorid loaches including the endemic lineages of the WG, would certainly help improving our understanding of their current‐day diversity and distribution patterns, as well as the larger‐scale evolutionary and biogeographical history of hillstream freshwater fishes in the Indian Subcontinent, Indo‐China and the Sunda Islands.

Arya Sidharthan, Rajeev Raghavan, Vasudevan Komalavally Anoop, Siby Philip and Neelesh Dahanukar. 2020. Riddle on the Riffle: Miocene Diversification and Biogeography of Endemic Mountain Loaches in the Western Ghats Biodiversity Hotspot. Journal of Biogeography. 47(12); 2741-2754. DOI: 10.1111/jbi.13972
twitter.com/JBiogeography/status/1314680473864429568
twitter.com/LabRajeev/status/1314746977343610881

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Parascolopsis akatamae, A New Species of Fluorescent Monocle Bream
JAKE ADAMS
Parascolopsis akatamae is a new species of dwarf monocle bream from Japan which has a very curious and unique feature. Fluorescence is well documented among many different groups of reef animals, especially the corals, but the new Akatamae bream exhibits a startling degree of natural fluorescence.
Nearly four years ago we shared our own experiments in photographing fluorescence in common reef fish, discovering highly fluorescent markings in common reef fish such as wrasses, pipefish, anthias, and a particularly brilliant jawfish. In recent years there has been a lot more investigation into the phenomenon of fluorescence in reef fish, some species of damselfish and wrasses showing very localized fluorescent patterns that are not visible under broad spectrum lighting.

The newly described Parascolopsis akatamae shares this unique, localized fluorescence and it has been used to distinguish it from a very similar congeneric species. The Akatamae Dwarf Monocle Bream is nearly identical to the closely related Parascolopsis eriomma under white light but the ‘pattern of biofluorescent emission’ is clearly different, with the former being having much brighter yellow-green fluorescence across the dorsal fin, and a bright coloration across the lower edge of the gills which is absent in the latter.
Alas, biofluorescence in reef fish is much more muted than it is in our aquarium corals, and requires very deep blue, near UV lighting spectrum as well as yellow orange barrier filters to see them, so this is not a fish that will ‘glow’ under typical blue aquarium lighting. However if you wanted to try, Parascolopsis akatamae has a wide distribution ranging from Japan to Taiwan, Philippines and even northern Indonesia. [BioTaxa]

From REEF BUILDERS

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Stigmatopora harastii • A New Species of Pipefish (Syngnathiformes, Syngnathidae) in Facultative Associations with Finger Sponges and Red Algae from New South Wales, Australia

Stigmatopora harastii
Short & Trevor-Jones, 2020

Harasti’s Pipefish or Red Wide-bodied Pipefish || DOI: 10.3897/zookeys.994.57160

Abstract
A new species of pipefish, Stigmatopora harastii sp. nov., is described based on the male holotype and two female paratypes, 136.3–145.5 mm SL, collected from red algae (sp.?) at 12 meters depth in Botany Bay, New South Wales (NSW), Australia. The new taxon shares morphological synapomorphies with the previously described members of Stigmatopora, including principle body ridges, fin placement, slender tail, and absence of a caudal fin. It is morphologically and meristically similar to Stigmatopora nigra, including snout length and shape, dorsal-fin origin on 6th–7th trunk ring, and lateral trunk ridge terminating on the first tail ring. Stigmatopora harastii sp. nov. is distinguished from its congeners, however, by characters of the head and first trunk ring, distinct sexual dimorphic markings on sides and venter of anterior trunk rings, and red background coloration in life. The new taxon can be further differentiated by genetic divergence in the mitochondrial COI gene (uncorrected p-distances of 9.8%, 10.1%, 10.7%, and 14.6%, from S. argus, S. macropterygia, S. narinosa, and S. nigra, respectively). The type locality is characterised by semi-exposed deep-water sandy areas interspersed with boulders, flat reefs, and an absence of seagrass beds, in which S. harastii has been observed living in facultative associations with a finger sponge and red algae at depths of 10–25 meters, compared to the shallow coastal and estuarine habitats preferred by the fucoid algae and seagrass-associating members of Stigmatopora. Stigmatopora harastii sp. nov. represents the fourth species of Stigmatopora recorded in temperate southern Australia.

Keywords: Botany Bay, COI, cryptobenthic, ichthyology, Jervis Bay, marine fish, morphology, South Pacific, Sydney, systematics, taxonomy

Stigmatopora harastii sp. nov.

Diagnosis: Stigmatopora harastii differs from its congeners by the following combination of morphological characters: median ridge, distinct, low, present on dorsum of head and first trunk ring starting from the posterior third of the frontal, over the supraoccipital, to the anterior and posterior nuchal plates; opercular ridge prominent, complete, not angled dorsad; lateromedial ridge, distinct, low, present between opercle and pectoral fin base; dorsal-fin origin on 6th–7th trunk rings, subdorsal rings 19–20 (12 trunk rings + 7 or 8 tail rings); lateral trunk ridge ends on first tail ring. Colouration: red background colour; dorsum of snout with large, irregular pale white spots; sides of head and anterior trunk rings with large, irregular pale white spots or with diffuse pale white stripe; venter of first trunk ring with distinct red elongated spots in longitudinal row, almost forming a stripe, on midline present in male (AMS I. 49510-001); venter of anterior trunk rings pale red with a large cluster of distinct red spots extending posteriad from second trunk ring in male (AMS I. 49510-001), few scattered small red spots in females (AMS I.1.47267).

Etymology: This species is named after David Harasti, one of the first to recognize S. harastii as being a new species, for recognition of his efforts towards conservation of Syngnathidae in Australia, and for being an aficionado extraordinaire of his beloved genus Stigmatopora. David has stated he counts green pipefish to fall asleep. Harasti’s Pipefish and the Red Wide-bodied Pipefish are proposed here as the common names for S. harastii.

Graham Short and Andrew Trevor-Jones. 2020. Stigmatopora harastii, A New Species of Pipefish in Facultative Associations with Finger Sponges and Red Algae from New South Wales, Australia (Teleostei, Syngnathidae). ZooKeys. 994: 105-123. DOI: 10.3897/zookeys.994.57160

Meet the spectacular Red Wide-bodied Pipefish: Australia's newest endemic fish species
australian.museum/blog/amri-news/meet-the-spectacular-red-wide-bodied-pipefish-australias-newest-endemic-fish-species

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Careproctus ambustus • A New Species of Snailfish (Cottiformes: Liparidae) Closely Related to Careproctus melanurus of the Eastern North Pacific

Careproctus ambustus Orr

in Orr, Pitruk, Manning, et al., 2020.
DOI: 10.1643/CI2020008
twitter.com/IchsAndHerps

Abstract
A new species, Careproctus ambustus, is described from 64 specimens based on evidence from morphological and molecular data. Specimens of Careproctus ambustus, new species, have been historically misidentified as the common Blacktail Snailfish, C. melanurus. The new species is distinguished from C. melanurus by its higher numbers of vertebrae (62–66 vs. 56–62 in C. melanurus), dorsal-fin rays (57–63 vs. 53–58), and anal-fin rays (51–55 vs. 46–51), and longer pelvic disc (14.1–21.2 vs. 12.6–20.7 % HL). In addition, the new species differs from C. melanurus by seven base pairs within a 492-base-pair region of the cytochrome oxidase c subunit 1 region, a 1.4% sequence divergence. Careproctus ambustus, new species, is found at depths of 58–1,172 m and ranges from Japan, through Alaska, to the west coast of Vancouver Island, British Columbia, where its distribution overlaps with C. melanurus, which ranges from southern Alaska and British Columbia to Baja California.

(A) Careproctus ambustus, new species, UW 152101, 323 mm, holotype, Aleutian Islands, 51.8402°N, 173.886°W, 330 m depth, photographed before fixation and preservation;

Careproctus (Allochir) ambustus, new species, Orr
Scorched Snailfish

Diagnosis.— Careproctus ambustus is distinguished from all other North Pacific species of Careproctus except C. melanurus by the combination of the shape of its pelvic disc, which is oval, longer than wide (vs. round or wider than long in other species of Careproctus), shallowly cupped (vs. flat or deeply cupped), and somewhat smaller than the orbit (vs. minute or large); shallowly notched pectoral fin with elongate rays in the lower lobe (vs. deeply notched with elongate or short rays, or shallowly notched with short rays in other species of Careproctus); and unique COI haplotypes (Orr et al., 2019). It is further distinguished morphologically from C. melanurus, with which it has been historically confused, by its higher vertebral and median fin-ray counts (vertebrae 61–67 vs. 56–62, dorsal-fin rays 57–63 vs. 53–59, anal-fin rays 51–57 vs. 46–52 in C. melanurus), in combination with its longer pelvic disc (14.1–21.2 vs. 12.6–20.7 % HL in C. melanurus).
...

Distribution.--Careproctus ambustus is known in the North Pacific Ocean from British Columbia, Alaska, Russia, and Japan (Fig. 3) at depths of 58 to 1,172 m, based on material examined and confirmed field identifications (Tokranov, 2000; Orr et al., 2014a, 2014b; G. R. Hoff, pers. comm., 2016). In the eastern North Pacific, it ranges from British Columbia off central Vancouver Island, throughout the Gulf of Alaska and Aleutian Islands, and into the eastern Bering Sea to at least 60.3°N (Hoff, 2016) and off Cape Navarin in the western Bering Sea (Parin et al., 2014). In the western North Pacific, it ranges from Kamchatka and the Kuril Islands, Russia (Orlov, 1998, 1999, 2001; Sheiko and Fedorov, 2000; Orlov and Tokranov, 2011), to the northwestern coast of Honshu, Japan (Kido and Shinohara, 1997).

Etymology.--The specific epithet of Careproctus ambustus is taken from the Latin ambusti, meaning “scorched,” referring to the black tail that contrasts with the pink to red anterior part of the body.

Distribution of Careproctus ambustus, new species (black), and C. melanurus (white) in the Bering Sea and North Pacific Ocean based on material examined. Each symbol may represent more than one capture. Bottom contour illustrated is 200 m.

James W. Orr, Dmitry L. Pitruk, Rachel Manning, Duane E. Stevenson, Jennifer R. Gardner and Ingrid Spies. 2020. A New Species of Snailfish (Cottiformes: Liparidae) Closely Related to Careproctus melanurus of the Eastern North Pacific. Copeia. 108(4); 711-726. DOI: 10.1643/CI2020008
twitter.com/IchsAndHerps/status/1329905499484065792

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Unravelling the Taxonomy of An Interstitial Fish Radiation: Three New Species of Gouania (Teleostei: Gobiesocidae) from the Mediterranean Sea and Redescriptions of G. willdenowi and G. pigra

Female Gouania pigra (Nardo, 1827) in the interstitial of pebbles (photo taken in aquarium).
(c) Trstenik (Pelješac, Croatia) – a site where G. pigra, G. adriatica sp. nov. and G. hofrichteri sp. nov. were found in sympatry.

in Wagner, Kovačić & Koblmüller, 2020
DOI: 10.1111/jfb.14558
Photographs by M. Wagner
twitter.com/Maximilian_Wa

Abstract
The clingfish (Gobiesocidae) genus Gouania Nardo, 1833 is endemic to the Mediterranean Sea and inhabits, unlike any other vertebrate species in Europe, the harsh intertidal environment of gravel beaches. Following up on a previous phylogenetic study, we revise the diversity and taxonomy of this genus by analysing a comprehensive set of morphological (meristics, morphometrics, microcomputed tomography imaging), geographical and genetic (DNA‐barcoding) data. We provide descriptions of three new species, G. adriatica sp. nov., G. orientalis sp. nov. and G. hofrichteri sp. nov., as well as redescriptions of G. willdenowi (Risso, 1810) and G. pigra (Nardo, 1827) and assign neotypes for the latter two species. In addition to elucidating the complex taxonomic situation of Gouania, we discuss the potential of this enigmatic clingfish genus for further ecological, evolutionary and biodiversity studies that might unravel even more diversity in this unique Mediterranean fish radiation.

Keywords: blunt‐snouted clingfish, cryptobenthic fish, DNA‐barcoding, intertidal, pebble beach

Maximilian Wagner, Marcelo Kovačić and Stephan Koblmüller. 2020. Unravelling the Taxonomy of An Interstitial Fish Radiation: Three New Species of Gouania (Teleostei: Gobiesocidae) from the Mediterranean Sea and Redescriptions of G. willdenowi and G. pigra. Journal of Fish Biology
DOI: 10.1111/jfb.14558
twitter.
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Epigonus indicus, a new species of deepwater cardinalfish (Perciformes: Epigonidae) from the Indian Ocean

IDREES BABU, K.K.; AKHILESH, K.V.

A new species of deepwater cardinalfish, Epigonus indicus, is described from two specimens, 105.2 and 100.2 mm SL, from Kavaratti Island, Lakshadweep (Laccadive) Sea, India. The specimens were collected from storage tanks at a desalination plant where seawater was piped up from 350–400 m depths. Diagnostic features distinguishing the new species from congeners include no pungent opercular spines, no maxillary mustache-like process, no projections on the symphysis of the lower jaw, ribs absent on the last abdominal vertebra, no isolated dorsal-fin spine between the first and second dorsal fins, gill rakers 26–27, pectoral-fin rays 15–17, pectoral-fin length about 22–23% SL, and body depth about 28–29% SL.

https://zenodo.org/record/4243312#.X6l7mvP7S1t

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Gerald R. Allen, Mark V. Erdmann and William M. Brooks: Acanthoplesiops jessicae, a new species of spiny basslet (Acanthoclininae: Plesiopidae) from Papua New Guinea, pp 57-65
Abstract
A new species of plesiopid fish, Acanthoplesiops jessicae, is described from Milne Bay Province, eastern Papua New Guinea on the basis of four specimens, 13.2-14.8 mm SL, collected from reef slopes at depths between 27 and 65 m. It is the only member of the genus having scales restricted to the rear half of the body and fused pelvic fins with branched inner rays. Other diagnostic features include dorsal-fin rays XIX,5; anal-fin rays VII,5; caudal-fin broadly connected by membrane to last dorsal and anal rays; cephalic sensory pores on dentary 3; colour in life generally brown with numerous small white spots on cheek, opercle, body and dorsal and anal fins; white to orange median dorsal stripe from tip of lower jaw to first dorsal spine; posterior edge of dorsal, anal and caudal fins with broad, orange submarginal zone and narrow white outer margin.
from Aquapress

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Jayasimhan Praveenraj, Tejas Thackeray and Shankar Balasubramanian: Schistura hiranyakeshi a new loach (Cypriniformes: Nemacheilidae) from Maharashtra, Northern Western Ghats, India, pp. 49-56
Abstract
Schistura hiranyakeshi, a new species of loach is described from Hiranyakeshi River, Amboli, Sindhudurg district, Maharashtra. It is unique among congeners from peninsular, northeastern, and central India, and Sri Lanka in having an incomplete lateral line with 6-7 pores and ending at a point vertical at half the length of the adpressed pectoralfin; dorsal fin and caudal fin devoid of spots or blotches; body with 9-10 bars that are wider or almost equal in width to the interspaces; dorsal fin, anal fin and sub-dorsal bars with a unique crimson color in adult males; lower lip with a black mark on each side of the median interruption in live and preserved specimens; and no suborbital flap or axillary pelvic lobe.

from Aquapress
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Gerald R. Allen, Mark V. Erdmann and William M. Brooks: Egglestonichthys rubidus, a new species of marine goby (Pisces: Gobiidae) from Milne Bay Province, Papua New Guinea, pp. 41-48
Abstract
Egglestonichthys rubidus n. sp. is described from two male specimens, 15.5-21.2 mm SL, collected from mud-bottom habitat in 18 m depth at Milne Bay Province, Papua New Guinea. Diagnostic features include: segmented dorsal and anal rays 7; pectoral rays 17-18; lateral scales 27-28; transverse scales 7; predorsal scales 13-18, extending to middleof interorbital; head and body scales entirely ctenoid, including breast, belly, prepelvic area, pectoral-fin base, predorsal, cheek, and opercle; cheek and opercle scales extend ventrally to lower margin; head pores absent; transverse papillae pattern on head, some rows raised, forming ridges; head, body, and fins generally red to reddish brown, outer edge of dorsal and anal fins with frost-like, white speckling. The new species differs from its four congenerics incounts for segmented dorsal and anal rays, pectoral rays, lateral scales, transverse scales, predorsal scales, arrangement of cephalic sensory papillae, and scale composition.
from Aquapress
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Gerald R. Allen and Helen K. Larson: Pseudogobiopsis rubrimaculosus, a new species of freshwater goby (Gobioidei: Gobiidae: Gobionellinae) from northwestern Papua New Guinea, pp. 33-40
Abstract
Pseudogobiopsis rubrimaculosus n. sp. is described from a freshwater stream in Sandaun Province, Papua New Guinea, on the basis of eight specimens, 16.6-24.2 mm SL. Diagnostic features include: second dorsal-fin elements I,7; anal-fin elements I,5-7 (modally 6); pectoral-fin rays 14-15 (modally 15), longitudinal scales 23-25 (modally 23); transverse scales (TRB) 7-8 (modally 7); predorsal scales 7-9 (modally 7), reaching to behind eyes;jaws enlarged in adult males; dorsal head pores and preopercular pores present; fourth dorsal spine longest, none elongate; pterygiophore formula 3-21210; generally tan with narrow brown scale outlines on upper body and double series of brownish to red-brown markings laterally on sides; dorsal and caudal fins with reddish spots, anal fin reddish, and pelvic fins blackish.
Full Text | PDF (460 KB)
From Aquapress

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Pomacentrus bangladeshius • A New Species of Damselfish (Perciformes, Pomacentridae) from Saint Martin’s Island, Bangladesh

Pomacentrus bangladeshius
Habib, Islam, Nahar & Neogi, 2020

DOI: 10.11646/zootaxa.4860.3.6
facebook.com/SAUFisheries

Abstract
A new species of damselfish, Pomacentrus bangladeshius, is described from 3 specimens, 67–77 mm standard length (SL), collected from Saint Martin’s Island, Bangladesh. The new species is distinguished from congeners in having the following combination of characters: XIV, 13 dorsal-fin elements; II, 14 anal-fin elements; 19 pectoral-fin rays; 18–19 lateral-line scales; 17–19 gill rakers on first arch; body depth 1.68–1.88 (1.88) in SL; snout 4.17–4.60 (4.17) in head length; head 2.91–3.09 (3.08) in SL; a prominent notch present between preorbital and suborbital; olive to dark brown body color, dark brown premaxilla, and yellow iris with a narrow bronze eye ring. The new species inhabits shallow reef flats around rock and coral outcrops. Phylogenetic analysis also shows the clear divergence of P. bangladeshius from other genetically closely related congeneric species retrieved from GenBank and that it represents a separate lineage.

Keywords: Pisces, Bengal demoiselle, morphology, DNA barcoding

Kazi Ahsan Habib, Md Jayedul Islam, Najmun Nahar and Amit Kumer Neogi. 2020. Pomacentrus bangladeshius, A New Species of Damselfish (Perciformes, Pomacentridae) from Saint Martin’s Island, Bangladesh. Zootaxa. 4860(3); 413–424. DOI: 10.11646/zootaxa.4860.3.6
facebook.com/SAUFisheries/posts/1023022994796022

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Rhynchobatus mononoke • A New Species of Wedgefish (Rhinopristiformes: Rhinidae) from Japan, with Comments on Rhynchobatus laevis (Bloch and Schneider 1801)

Rhynchobatus mononoke
Koeda, Itou, Yamada & Motomura, 2020

モノノケトンガリサカタザメ ||  DOI: 10.1007/s10228-020-00777-z

Abstract
Rhynchobatus mononoke sp. nov. (Rhinopristiformes: Rhinidae) is described from mature male and female specimens from southern Japan. A juvenile specimen, newly born from a captive individual collected from Kagoshima, is also referenced (non-type). The new species can be distinguished from congeners by a combination of its obtusely wedge-shaped snout, bluntly rounded dorsal fins, first dorsal fin originating about level with the pelvic-fin origin, and the outer fold on the spiracle posterior margin more pronounced than the inner fold. Distinctive coloration of the new species included a black blotch, followed by a single white spot (rarely absent) posterodorsally on the middle of the pectoral disc, and a large black blotch covering the anterior half of the undersurface of snout. Distinct white spots distally on the pectoral disc to the middorsal area were absent. Most previous records of species of Rhynchobatus in Japanese waters were reidentified as Rhynchobatus australiae, except for the records from the northern East China Sea. Rhynchobatus mononoke appears to be endemic to southern Japan.

Keywords: Rhynchobatus australiae, Rhynchobatus djiddensis, Rhynchobatus laevis, Taxonomy, Endemic species, East China Sea, Rays

Fig. 1: Fresh holotype of Rhynchobatus mononoke sp. nov., off Satsumasendai, Kagoshima, Japan. KAUM–I. 80332, 1167 mm TL, male

Rhynchobatus mononoke sp. nov.

(New English name: Japanese Wedgefish;
new standard Japanese name: Mononoke-tongarisakatazame
モノノケトンガリサカタザメ)

Rhynchobatus djiddensis (not Forsskål 1775): Yamada et al. 2007: 94, pl. 5–5, (northern East China Sea); Kagoshima City Aquarium Foundation 2008: 32, fig. (Kagoshima, Japan, photograph of freshly captured individual); Kagoshima City Aquarium Foundation 2018: 37, fig. (Kagoshima, Japan, photograph of freshly captured individual).

Fresh paratype of Rhynchobatus mononoke sp. nov., off Nagasaki, Japan. KBF-I 1085, 1295 mm TL, male

Etymology. The specific name of the new species, mononoke - もののけ, means “specter” in Japanese, due to the ventral surface of specimens appearing like a traditional Japanese specter, wearing a triangular white hat (crown) on its forehead. The name is used as a noun in apposition.

Keita Koeda, Masahide Itou, Morihiko Yamada and Hiroyuki Motomura. 2020. Rhynchobatus mononoke, A New Species of Wedgefish (Rhinopristiformes: Rhinidae) from Japan, with Comments on Rhynchobatus laevis (Bloch and Schneider 1801). Ichthyological Research. DOI: 10.1007/s10228-020-00777-z

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Oreoglanis omkoiense • A New Torrent Catfish (Siluriformes, Sisoridae) from northern Thailand

Oreoglanis omkoiense
Suvarnaraksha, 2020

RAFFLES BULLETIN OF ZOOLOGY. 68
facebook.com/ApinunSuvarnaraksha7

Abstract
Oreoglanis omkoiense, new species, is described from the Maetuen River basin, a tributary of Ping River in northern Thailand, it is found in the highland stream. This species is a member of the O. siamensis species group, characterised by a lower lip with median notch and posterior margin entire. Oreoglanis omkoiense has a long adipose fin base length, short post-adipose fin, long nasal barbels reaching anterior margin of eye, tip of maxillary barbel pointed, pectoral fin tip not reaching pelvic-fin origin, short pelvic fin, long pre-dorsal length, and thick and short caudal peduncle.

Key words. Omkoi, Metuen River, conservation, fish diversity, Southeast Asia

Fig. 1.  Oreoglanis omkoiense, new species, Huai Jino, Baan Huai Jino, Omkoi Subdistrict, Omkoi District, Chiangmai Province. Holotype, MARNM 6447, 91.86 mm SL.
(A = lateral view, B = dorsal view and C = ventral view)

Oreoglanis omkoiense, new species

Diagnosis. Oreoglanis omkoiense, new species, belongs to the O. siamensis species group, as it possesses a distinct median notch on the posterior margin of the lower lip. This species differs from its congeners in having the following combination of characters: maxillary barbel with pointed tip, long nasal barbel 25.0–32.9%SL, long pre-dorsal 33.2–39.2%SL, pre-ventral length 36.1–39.2%SL, height of dorsal fin 15.4–20.3%SL, length of adipose fin 32.3– 39.6%SL, post-adipose length 5.7–8.8%SL, caudal peduncle depth 2.1–3.3 times its length, head width 18.7–22.9%SL and 90.2–96.8%HL, eye diameter 9.2–13.1%HL, inner mandibular barbel 21.8–30.5%HL, and an emarginate caudal fin with upper and lower first principal rays of approximately equal length.

Etymology. Named after Omkoi, the district of the locality where the new species was discovered.

Distribution. Found in the Metuen River basin, a tributary of the Ping River drainage (one of four main tributaries of the Chao Phraya River), in Chiang Mai, Thailand.

A, Oreoglanis siamensis MARNM 6338, juvenile 32.33 mm SL;
B, Oreoglanis siamensis MARNM 7144, adult 74.19 mm SL, Meklang River, Inthanon Moutain, Jomtong, Chiangmai,, date 23 September 2008;
and C,  Oreoglanis omkoiense, new species, holotype, MARNM 6333, adult, 91.86 mm SL, Huai Jino, Omkoi district, Chiangmai.

Apinun Suvarnaraksha. 2020. Oreoglanis omkoiense: A New Torrent Catfish from northern Thailand (Pisces: Siluriformes, Sisoridae). RAFFLES BULLETIN OF ZOOLOGY. 68: 779–790.

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Sex-specific responses to competitive environment in the mosquitofish Gambusia holbrooki
- Samuel Brookes,
- Maider Iglesias-Carrasco,
- Loeske E. B. Kruuk &
- Megan L. Head
Evolutionary Ecology (2020)Cite this article
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AbstractThe competitive environment that animals experience during development constitutes an important source of selection that can influence the development, expression and evolution of traits. Here, we examine how the sex of focal and “competitor” individuals interact to affect development in the Eastern mosquitofish Gambusia holbrooki. We raised individuals of both sexes either alone or in the presence of a male or female conspecific (hereafter “competitor”), and measured their juvenile growth rate, time to maturity and size at maturity. For males, we also measured their gonopodium length, sperm quantity, and sperm velocity. We found that responses to the competitive environment were dependent on the sex of the focal individual, the sex of their “competitor” and sometimes an interaction between the two. When there was another fish present, regardless of its sex, males had slower growth rates and took longer to mature, but eventually matured at the same size. Females also showed slower growth rates in the presence of a competitor, but in contrast to males, reached maturity sooner and at a smaller size than when there was no competitor present. Presence of a competitor influenced male sexual traits, however there was little evidence that these effects were mediated by the sex of the other fish. Males reared with another fish had longer gonopodia for their body size, as well as fewer and faster sperm. Our results suggest that effects of the competitive environment are different for males and females, potentially due to sex differences in adult life history strategies. Further, for males, both life history traits and sexual traits were influenced by the competitive environment. For life history traits this effect appears to result from decreased resources and/or increased energy expenditure, but for sexual traits, effects appear to be mediated, in part, by the social environment.
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Data availabilityAll data will be published on DRYAD and is available for reviewers at https://datadryad.org/stash/share/lNz54rPe9ZnLwzDCXDWywb8s0cSWJfPsJse4O0gUOWU.

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Ammoglanis natgeorum • A New Miniature Pencil Catfish (Siluriformes: Trichomycteridae) from the lower Atabapo River, Amazonas, Venezuela

Ammoglanis natgeorum
Henschel, Lujan & Baskin, 2020

DOI: 10.1111/jfb.14515
twitter.com/DrNathanLujan

Abstract
A new species of the sand‐dwelling catfish genus Ammoglanis is described from a marginal habitat of the lower Atabapo River, a left‐bank blackwater tributary of the upper Orinoco River in Amazonas, Venezuela, adjacent to the border with Colombia. Ammoglanis natgeorum is distinguished from all congeners by trunk pigmentation pattern consisting of scattered ventral chromatophores concentrated around the anal‐fin base and numerous additional meristic and anatomical characteristics. A. natgeorum is the second species of Ammoglanis described from the Orinoco River basin after Ammoglanis pulex, and several shared character states (e.g., eight total dorsal‐fin rays, overall coloration pattern and presence of two finger‐like papillae posterior to chin) suggest that it is more closely related to Ammoglanis obliquus (from the central Amazon basin) and A. pulex than to other congeners.

Keywords: blackwater, Orinoco basin, psammophily, riverine infauna, Sarcoglanidinae, taxonomy

Field photos of a live Ammoglanis natgeorum sp.n. shortly after capture
Ammoglanis natgeorum sp. nov.

Etymology: The specific epithet natgeorum honours the employees of the National Geographic Society (commonly abbreviated as NatGeo), without whose generous support this research would not have been possible. The type specimens were collected during field work funded by National Geographic CRE grant 8721‐09 to NKL, and the first author's research on Ammoglanis and other trichomycterid catfishes has been supported by a NatGeo Early Career Grant.

Elisabeth Henschel, Nathan K. Lujan and Jonathan N. Baskin. 2020. Ammoglanis natgeorum, A New Miniature Pencil Catfish (Siluriformes: Trichomycteridae) from the lower Atabapo River, Amazonas, Venezuela. Journal of Fish Biology. DOI: 10.1111/jfb.14515
twitter.com/DrNathanLujan/status/1311098685368012800
facebook.com/NKLujan/posts/10108885306955501

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Aquashella Orlando, June 12-13th, 2021, is the newest addition to the Aquashella line-up of festivals for 2021.
Be sure to follow Aquashella on Facebook and Instagram for more updates on all of their events!
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- A thirteen-million-year divergence between two lineages of Indonesian coelacanths
  Note: Figures in text are links to original pictures
  - Kadarusman,
  - Hagi Yulia Sugeha,
  - Laurent Pouyaud,
  - Régis Hocdé,
  - Intanurfemi B. Hismayasari,
  - Endang Gunaisah,
  - Santoso B. Widiarto,
  - Gulam Arafat,
  - Ferliana Widyasari,
  - David Mouillot &
  - Emmanuel Paradis
  Scientific Reports volume 10, Article number: 192 (2020) Cite this article
  - 4934 Accesses
  - 1 Citations
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  - A Publisher Correction to this article was published on 10 March 2020
  - This article has been updated
  AbstractCoelacanth fishes of the genus Latimeria are the only surviving representatives of a basal lineage of vertebrates that originated more than 400 million years ago. Yet, much remains to be unveiled about the diversity and evolutionary history of these ‘living fossils’ using new molecular data, including the possibility of ‘cryptic’ species or unknown lineages. Here, we report the discovery of a new specimen in eastern Indonesia allegedly belonging to the species L. menadoensis. Although this specimen was found about 750 km from the known geographical distribution of the species, we found that the molecular divergence between this specimen and others of L. menadoensis was great: 1.8% compared to 0.04% among individuals of L. chalumnae, the other living species of coelacanth. Molecular dating analyses suggested a divergence date of ca. 13 million years ago between the two populations of Indonesian coelacanths. We elaborate a biogeographical scenario to explain the observed genetic divergence of Indonesian coelacanth populations based on oceanic currents and the tectonic history of the region over Miocene to recent. We hypothesize that several populations of coelacanths are likely to live further east of the present capture location, with potentially a new species that remains to be described. Based on this, we call for an international effort to take appropriate measures to protect these fascinating but vulnerable vertebrates which represent among the longest branches on the Tree of Life.
  IntroductionCoelacanth fishes of the genus Latimeria are the only living representatives of the Actinistia, a group of vertebrates that flourished between the Early Devonian (ca. 400 millions of years ago, Ma) and the Late Cretaceous (ca. 80 Ma)1,2,3. Fossil fishes belonging to the subclass Actinistia have been found around the world, whereas the two known living species of coelacanth are found only in the Western Indian Ocean (L. chalumnae4) and in Indonesia (L. menadoensis5). Sampling living specimens of coelacanths is a difficult endeavour, because they live at depths of 200 to 400 m although they occasionally occur at shallower depths of 100 m below the surface, while catches by fishermen are sporadic. Furthermore, direct observations suggest that coelacanths have a very sparse distribution and live in groups of a few tens of individuals6,7,8. Our current knowledge on the genetic diversity of these enigmatic animals suggests that L. chalumnae is distributed along several thousands kilometers of the South-East African coast and has very low genetic diversity based on mitochondrial genome markers9,10 and on nuclear microsatellites11, whereas L. menadoensis is distributed in a very small area near the northern part of the island of Sulawesi, where only a few individuals have been studied genetically but show very close genetic affinities12,13 (Fig. 1). These population genetic data strongly suggest that both species may represent the relicts of an ancient clade of early tetrapods decimated by extinctions14. Surprisingly, no specimens have been reported outside of these two restricted regions, while the existence of other coelacanth sub-species or species has never been mentioned.
  Figure 1
  Known geographical distributions of the two species of Latimeria. The localities where specimens of L. menadoensis were captured are shown in bold, and the localities where this species has been observed in situ are in italics. The rectangle shows the limits of Fig. 5.
  
  Full size imageWe here report results of the genetic analyses of a new coelacanth specimen, allegedly belonging to L. menadoensis, caught recently in West Papua, Indonesia, approximately 750 km from Sulawesi. We find significant but Neogene-dated genetic differences between this individual and populations of L. menadoensis found in Sulawesi, challenging the view that living coelacanths are merely remnant populations of very anciently diverged lineages that have experienced little evolution since the early–mid Cenozoic.
  ResultsWe sequenced 8164 base pairs (bp) of the mitochondrial genome of the new specimen, which represent 49.6% of the whole mitogenome of the Latimeria specimen from Manado (GQ911586, 16 446 bp). The alignement of these two sequences showed four deletions of one base (in tRNA-Phe, 16S rRNA, tRNA-Cys, and D-loop), and one deletion of two bases (D-loop) in the new specimen sequence, as well as two deletions of one base (in 16S rRNA and tRNA-Met) in GQ911586. This two-sequence alignment had thus 16 448 bp. The alignment with two genomes of L. chalumnae (AB257297, AP012199) added more gaps and resulted in an alignement with 16 454 bp. Alignments of 27 sequences of Latimeria spp., including sequences from previously sampled populations, generated with MUSCLE or with MAFFT (see Methods), confirmed this result. The inferred maximum-likelihood (ML) gene tree topology showed unambiguously that the two Indonesian coelacanths are sister-lineages with a level of divergence never observed among the individuals of L. chalumnae (Fig. 2). The bootstrap analysis gave the following 95% confidence intervals (CI) for the two terminal branch lengths leading to the Indonesian coelacanths: [0.008, 0.013] for the Papua sequence, and [0.007, 0.013] for GQ911586. The 95% CI for the length of the internal branch connecting the two Indonesian specimens to the L. chalumnae clade was [0.034, 0.042].
  Figure 2
  Maximum likelihood unrooted phylogeny reconstructed with 27 mitochondrial genome sequences of Latimeria. The Roman numerals indicate sequences that are identical (I: AP012182, AP012184–AP012187, AP012189, AP012193, and AP012195; II: AB257297, AP012179, AP012180, and AP012188; III: AB257296 and AP012177; IV: AP012178 and AP012196; and V: AP012194 and AP012197).
  
  Full size imageThe pairwise genetic distances among individuals of L. chalumnae were zero for all genes except for tRNA-GLn (0.014 between AB257297 and AP012199). In four cases (tRNA-Phe, tRNA-Gln, tRNA-Asn, and tRNA-Tyr), the distance between the two Indonesian specimens was greater than the distance between the new specimen and L. chalumnae (Fig. 3). In the twelve other cases, the opposite was observed, particularly for protein-coding and rRNA-coding sequences which are much longer than those coding for tRNAs. The p-distance between the two Indonesian specimens calculated using the first 655 sites of the COI gene (the segment used for fish DNA barcoding) was 0.0122.
  Figure 3
  Uncorrected genetic distances for 16 genes of the mitogenome of Latimeria. Open symbols show distances between the two Indonesian specimens; filled symbols show distances between the new Indonesian specimen and a specimen of L. chalumnae.
  
  Full size imageIn addition to the deletions noted above during alignment, the two Indonesian individuals showed 149 base differences, whereas the number of differences between two individuals of L. chalumnae varied between 0 and 10. Among the 13 proteins coded by the mitogenome, three had their genes sequenced in the new specimen: ND1, ND2, and COI. While no amino acid (AA) substitutions were observed among the 12 unique sequences of L. chalumnae, 35 AA replacements were observed between the Indonesian individuals and L. chalumnae (Table 1). Interestingly, it seems that all these replacements are the result of single events occurring on one of the three longest branches of the tree on Fig. 2. Among the 11 AA differences between the two Indonesian individuals, six can be inferred to result from substitutions that happened on the terminal branch leading to the new sequence, and five on the branch leading to GQ911586. The other 24 AA substitutions happened on the internal branch connecting the two main clades of Latimeria.
  Table 1 Replacements of amino acids among the new coelacanth specimen from Papua (Papua), an individual from Manado (GQ911586), and an individual belonging to L. chalumnae (AP012199).
  Full size tableThe ML phylogenetic analysis with ten mitogenomes resulted in an unambiguous tree that highlighted well-established relationships among the main clades of vertebrates (Fig. 4). A remarkable result from this phylogeny is the substantial variation in molecular evolutionary rate among sampled lineages. It is also noteworthy that Pan was found to be a sister-lineage of the clade Andrias + Lacerta in the NJ tree which was used as initial tree of the ML analysis.
  Figure 4
  (A) Maximum likelihood phylogeny estimated with phangorn. The bold numbers give the node support bootstrap values (1000 replications). The branch lengths are in expected number of substitutions. (B) Dated phylogeny (chronogram) estimated by Bayesian inference. The rectangles show the credibility intervals from the highest posterior densities.
  
  Full size imageThe estimated divergence date for the two Indonesian coelacanth populations was inferred to be 13.3 Ma by the ML method, and 12.4 Ma by the Bayesian method (95% highest posterior density, HPD: 1.5–34.1), in the middle Miocene.
  The distance between Manado (where all individuals of L. menadoensis were caught until the new specimen was captured, although some individuals were observed elsewhere; see Discussion section) and the location of the capture of the new individual was estimated to be 752 km (geodesic distance). The bathymetry around these locations is extremely variable with trenches more than 8000 m deep as well as shallow oceanic shelves (Fig. 5). Manado and Waigeo are separated by the island of Halmahera and a deep channel separates this island from Sulawesi. We extracted 25 724 temperature records taken at depth between 0 and 2011 m north of Papua. Latimeria chalumnae is reported to prefer water temperatures ranging from 16 °C to 23 °C6, and these temperatures were observed in our data at depths between 110 m and 270 m (Fig. 6).
  Figure 5
  (A) Bathymetry of Eastern Indonesia. The arrows show the main surface currents. (B) Bathymetry and elevation profile between Manado and Waigeo.
  
  Full size image
  Figure 6
  Temperatures and depths recorded close to the capture location of the new specimen (blue dots). The dashed lines show the depth range observed for L. chalumnae by Fricke et al.6, and the grey rectangle shows the depth and temperature ranges observed by Iwata et al.8 for L. menadoensis.
  
  DiscussionBefore the capture of the new Latimeria specimen reported in this paper, all known specimens of L. menadoensis were captured near Manado in North Sulawesi8. However, submarine observations of coelacanths have been reported 360 km southwest of Manado15 and in the Cendrawasih Bay to the north of Papua8, indicating potential for undetected populations. Therefore, our findings provide an important contribution to better understand the diversity, distribution, and evolution of this important group of vertebrates16,17,18.
  We acknowledge several limitations of our study with regard to relying on a mtDNA-only dataset from a single individual of the new population. For example, examining loci from both nuclear and mitochondrial genomes has revealed cases of cytonuclear discordance in other taxonomic groups19,20,21. In the current investigation, we may have detected a divergent mitochondrial lineage in L. menadoensis. However, nuclear loci may reveal contemporary gene flow between populations from Manado and Papua New Guinea. Sampling additional specimens and expanding future molecular investigations to include unlinked nuclear loci would extend our understanding of species limits and the evolutionary history of Latimeria. However, the most striking result from our analyses is the relatively deep but Neogene molecular divergence between the specimen from Papua and its counterpart representing the previously studied population from Manado. This divergence is apparent at the mitochondrial DNA level but also implied a substantial number of AA replacements in protein-coding mitochondrial genes, something that has not to-date been observed among L. chalumnae individuals. The ML bootstrap analysis of branches leading to the Indonesian coelacanth fish populations strongly suggests that molecular evolutionary rate was equal in these two lineages, thus supporting the hypothesis of a molecular clock for the mitochondrial genome within this clade. Furthermore, the number of amino acid substitutions were found to be almost the same on both branches (five and six, respectively).
  This marked pattern of genetic divergence between the two Indonesian coelacanths suggests that it would be worthwhile to revisit an earlier hypothesis15, namely that the two known species of Latimeria have different habitats and probably different life-history strategies that could be correlated to differences in their respective environments. East African coelacanth fish live in relatively calm oceanic waters while Indonesian coelacanth fish inhabit more disturbed and turbulent waters7,15. The eastern part of the Indonesian archipelago is characterized by a complex system of strong oceanic currents22,23. This complexity is partly caused by the meeting of several currents at the equator, where the Coriolis force becomes inverted. Particularly, the New Guinea Coastal Current (shown on the right-hand side of Fig. 5A) flows westward along the main coast of New Guinea, then northward after the island of Halmahera and finally eastward a few hundred kilometers further north. This phenomenon creates a whirlpool known as the Halmahera Eddy in the center of this loop with a depression of up to 120 m24. A similar phenomenon exists around Manado with the Mindanao Current (on the left-hand side of Fig. 5A) and the Mindanao Eddy west of Manado. These sea surface currents flow between 0 and 350 m below sea surface. The Maluku Sea appears to separate both populations of Indonesian coelacanths. These oceanographic observations agree with the existence of a strong barrier between Sulawesi and Halmahera which has been observed in several groups of marine organisms25,26.
  A crucial question, given these results, is whether this system shaped by strong sea surface currents has been stable over geological time, to maintain the divergence of coelacanth populations over thousands to millions of years. Modelling studies suggest that the contrasted oceanic topography is an important factor in this region where waters from the northern and southern hemispheres meet23,24. This topography is the result of a long and complex tectonic history27,28. One of the most dramatic geological events was the uplift of New Guinea by the accretion of terranes (pieces of tectonic plates) with different plates and arcs between 42 Ma and 18 Ma29. The climax of changes in plate boundaries seem to have happened between about 25 and 20 Ma27. Therefore, this hydrological connectivity among marine populations or species was still possible before 20 Ma and was probably interrupted after this date. Our molecular dating analysis is consistent with these geological inferences and supports the interpretation of major barriers to connectivity between New Guinea and Sulawesi existing since around 20 Ma in the early- to mid-Miocene.
  The molecular divergence observed between the individuals from Waigeo and Manado is further evidence of a low rate of molecular evolution among the lineages of Latimeria. Remarkably, such a low rate of molecular evolution was observed in previous studies comparing the two species using mitochondrial13 or nuclear genomes30. The observed divergence for the COI-based barcode between the two Indonesian specimens (1.22%) was greater than among individuals of the same species for several groups of fishes which averaged 0.59%31, 0.89%32, or 0.29%33. This suggests that the new specimen is genetically distinct and may warrant formal recognition as a species, although in-depth taxonomic assessment would be required to test this hypothesis.
  Iwata et al.8 performed 1173 dives in Sulawesi and Biak and observed 30 coelacanths at depths 115.6–218.9 m and temperatures 12.4–21.5 °C (Fig. 6). These values widely overlap with those observed for L. chalumnae6, though depths for the latter are slightly shallower. It is too premature to conclude that the temperature tolerances of these species are different, although the relatively old divergence between them (30–40 Ma) is likely to result in environmental niche divergence through time.
  Based on the available information from our results, in combination with patterns of oceanic circulation from the region, we hypothesize that the Latimeria specimen captured in Waigeo in July 2018 belongs to L. menadoensis, although it is likely that this specimen belongs to a distinct and as-of-yet undescribed species or subspecies of Latimeria. We urgently call for future taxonomic studies integrating morphological and genetic data from multiple specimens from different L. menadoensis populations, in order to test this hypothesis. Nevertheless, our results suggest that L. menadoensis likely has a much wider geographical range than previously thought. Given the presence of this specimen nearby the New Guinea Coastal Current, we hypothesize that L. menadoensis populations can occur along the coast of New Guinea and probably further east of New Guinea. The waters of the northwest coast of New Guinea have been poorly sampled and it would not be surprising to find several populations of coelacanths in the region.
  In light of our findings as well as the unique biology of coelacanths in general, we call for an international effort to take appropriate measures to protect these fascinating but vulnerable vertebrates. The conservation of relict species including the unique representatives of particular phylogenetic groups and their likely unique combinations of characters is key to conserve phylogenetic diversity represented by the Tree of Life. Yet, the existing global system of marine protected areas (MPAs) may fail to cover areas where these relict species are located34. If MPAs are to protect the unique and diverse marine lineages across the Tree of Life, we need to carefully reconsider the protection of East Indonesian coasts where this new lineage of coelacanth occurs.
  MethodsSamplingMr. Dava Santoso, a recreational fisherman, accidentally caught a coelacanth on July 1, 2018, off southeast Waigeo Island (West Papua, Indonesia; Fig. 5A). The specimen was captured at a depth, estimated by Mr. Santoso, of about 300 m with a handline while using sardine fillets as bait. The gender of the specimen was not identified, and the body was around 1 m long. Unfortunately, the specimen was filleted and mostly consumed before the staff from Loka Pengelolaan Sumberdaya Pesisir dan Laut Sorong (LPSPL Sorong, Indonesia) and the Politeknik Kelautan dan Perikanan Sorong (Politeknik KP Sorong) obtained tissue samples from the fish and preserved them in absolute ethanol (100%).
  Laboratory analysesLaboratory analyses were carried out at the molecular laboratory of the Ministry of Marine and Fisheries Affairs in Jakarta, Indonesia. Whole genomic DNA was extracted using ZR Tissue & Insect DNA MiniPrep (Zymo Research, D6016). We amplified half of the whole mitochondrial genome including the whole control region (D-loop), 12S, 16S, ND1, ND2, and COX1, using 12 pairs of primers described in13 (Table S1) with an initial denaturation step at 94 °C for 2 min, a cycle of three steps (denaturation at 94 °C for 30 sec; annealing at 55 °C for 40 sec; elongation at 72 °C for 1 min) repeated 35 times, and a final extension of 10 min at 72 °C. The double-stranded PCR products were purified and sequenced using the BigDyeTM Terminator v3.1 Cycle Sequencing Kit at 1st BASE Manufacturer, Axil Scientific Pte Ltd., Singapore.
  Statistical analysesWe first compared the new mitogenome sequence with the sequence from an individual of L. menadoensis caught in Manado (GenBank accession no: GQ91158613) and 25 sequences of L. chalumnae from Comoros (2) and Tanzania (23) (AB257296, AB257297, AP012177–AP0121989,10). We performed manual sequence alignments as well as alignments with MUSCLE35 and MAFFT36. We examined the base substitutions as well as the amino acid substitutions for the protein-coding sequences with ape37, and performed maximum likelihood (ML) phylogenetic analyses under a GTR + Γ + I model using the phangorn R package38. Confidence in the inferred clades was assessed using a bootstrap approach with 1000 pseudoreplicates39. Because we used a general phylogenetic model with a distinct substitution rate for each branch (i.e., not a molecular clock model), we tested the hypothesis that the rate of molecular evolution was the same between specimens of Indonesian Latimeria using a bootstrap with 1000 pseudoreplicates and comparing the distribution of these estimates. This test makes no assumption on the substition rates on the other branches of the tree. The uncorrected genetic distances (also known as p-distances) were calculated separately for 16 sequences coding for tRNAs (11), rRNAs (2), or proteins (3) using annonations from GenBank.
  Subsequent to the above steps, we dated the divergence between the two specimens of Latimeria found in Indonesia by reconstructing a phylogeny with the mitogenomes of several vertebrates, including the followings: Acipenser dabryanus (KP981414), Gymnarchus niloticus (AP008930), Neoceratodus forsteri (AJ584642), Andrias japonicus (AB208679), Lacerta bilineata (NC_028440), and Pan troglodytes (NC_001643). These species were selected in order to provide a reasonable sample whose genomes and relationships to Actinistia are well characterized40,41. A progressive alignment of these six additional genomes was performed on the alignement obtained with the new sequence, GQ911586, AB257297, and AP012199 using MAFFT. An ML tree was estimated with this alignment under a GTR + Γ + I model and then dated with the ML method42 implemented in ape as well as an independent analysis using the Bayesian approach implemented in BEAST 2.5.243. The ML analysis used Sanderson’s correlated rate model where the substitution rates are assumed to be positively correlated on contiguous branches of the tree44, whereas the Bayesian analysis assumed a relaxed lognormal clock model and Yule priors on the distribution of trees. Three calibration points were used in both analyses41: 416.1–421.75 Ma for the divergence between fishes and tetrapods (Actinopterygii–Sarcopterygii), 330.4–350.1 Ma for the divergence between amniotes and amphibians (Reptiliomorpha–Batrachomorpha), and 312.3–330.4 Ma for the divergence between reptiles and mammals (Sauropsida–Synapsida). These ages were considered as soft bounds in both analyses using normal priors in Bayesian analysis. The posterior distribution of the parameters were estimated by Markov chain Monte Carlo (MCMC) run during 107 generations sampled every 103 and discarding the first 106 generations as burn-in period.
  In order to assess potential dispersal routes between Manado and Waigeo, we established the bathymetric profile of the region using the GIS database provided by the National Oceanic and Atmospheric Administration (https://www.ngdc.noaa.gov/mgg/global/relief/ETOPO1/data/bedrock/grid_registered/georeferenced_tiff/, accessed 2019-03-18). These data were processed with the R package rgdal45. Because no vertical ocean profiles of temperature data are available on the location of the capture of the new specimen, we used data from the closest stations which are made available by the ARGO broad-scale global array of temperature and salinity profiling floats in the northeast of Waigeo. The area is crossed by the Halmahera Eddy throughflow from the Pacific Ocean to the Indian Ocean. We can therefore consider that the characteristics of the seawater column observed by the selected ARGO profiling floats are similar to those in Waigeo. ARGO is an international program that calls for the deployment of 3,000 free drifting profiling floats, distributed over the global oceans which measure the temperature and salinity in the upper 2 000 m of the ocean. The observation data are uploaded in the Global Data Assembly Centre (Argo GDAC46). Each ARGO autonomous profiling CTD has several sensors on board, including a Sea-Bird SBE 41/41CP for the seawater temperature and salinity acquisition, and a Druck 2900 PSIA for the pressure acquisition. Argo CTD module was developed in response to the scientific need for highly stable and accurate temperature and salinity on profiling floats, with high and manual quality control process47. The seawater temperature profiles were extracted from the ARGO database (http://www.ifremer.fr/co-argoFloats/float?ptfCode=5904515) with an accuracy of 0.002 °C and a resolution of 0.0001 °C for the temperatures, and an accuracy of 1.5% and a resolution 0.01 dbar for the pressure. We extracted 209 profiles recorded during March 2019 at longitudes between 141.02°E and 161.21°E and latitudes between 8.18 °S and 1.67 °N.
  Except for the BEAST analysis, all analyses were done with R version 3.5.248.
  Data availabilityThe new sequence was deposited in NCBI GenBank (accession number: MK748470).
  
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Scorpaena vesperalis • Review of the Scorpaena papillosa Species Complex (Scorpaeniformes: Scorpaenidae) with Description of A New Species from southwestern Australia

Scorpaena vesperalis
Wibowo & Motomura, 2020

DOI: 10.11646/zootaxa.4852.5.2
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Abstract
A taxonomic review of the Scorpaena papillosa species complex, defined here as having 10 dorsal-fin soft rays, coronal spines, and two upwardly directed spines on the lacrimal bone, resulted in the recognition of two species and two subspecies, Scorpaena papillosa (Schneider & Forster, 1801) including two subspecies, i.e., S. papillosa papillosa (New Zealand) and S. papillosa ergastulorum Richardson, 1842a (southeastern Australia), and Scorpaena vesperalis n. sp. (southwestern Australia). Scorpaena p. papillosa and S. p. ergastulorum, are redescribed, with designation of a neotype for S. p. papillosa. Scorpaena vesperalis n. sp., described from coastal waters off southwestern Western Australia on the basis of 57 specimens, is characterized as follows: pectoral-fin rays 14–16; longitudinal scale rows 37–41; body depth 32.3–39.5 % of SL; upper-jaw length 19.6–22.5 % of SL; maxilla depth 5.7–7.3 % of SL; postorbital length 18.2–21.3 % of SL; least distance between interorbital ridges 1.4–2.7 % of SL; 1st anal-fin spine length 7.2–10.0 % of SL; anterior lacrimal spine simple, without additional small spinous points on its posterior margin; a single united pore behind the lower jaw symphysial knob; relatively large supraocular tentacle; all fins of preserved specimens usually uniformly whitish to translucent; and small body size (maximum recorded length 67.6 mm SL). The new species is likely endemic to southwestern Australia. Morphological ontogenetic changes in the relative lengths of some body proportions in the three taxa are also discussed.

Keywords: Pisces, scorpionfish, taxonomy, morphology, distribution, subspecies

Fresh specimens of Scorpaena vesperalis n. sp. WAM P. 28521-003, holotype, 58.7 mm SL
(Photo by Western Australian Museum - WAM)

Scorpaena vesperalis n. sp.
Dwarf Red Scorpionfish

Etymology. The species name from the Latin vesperalis, meaning west, is derived from the type locality of the species (Western Australia), which is also the westernmost occurrence of the S. papillosa complex.

Distribution. Distributed off southwestern Australia, ranging from Southern Group, Houtman Abrolhos (28°S) to the Albany coast (35°S) (Fig. 4). Specimens examined in this study were collected mainly from shallow rocky reefs at depths between 0–37 m (a single specimen had been collected from 188 m).

Kunto Wibowo and Hiroyuki Motomura. 2020. Review of the Scorpaena papillosa Species Complex (Teleostei: Scorpaenidae) with Description of A New Species from southwestern Australia. Zootaxa. 4852(5); 527–546. DOI: 10.11646/zootaxa.4852.5.2
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A new species of Knodus Knodus geryi, (Characiformes: Characidae) from the Rio Cupari drainage, lower Rio Tapajós basin, Brazil

DEISE J. DOS ANJOS DE SOUSA, CÁRLISON SILVA-OLIVEIRA, ANDRÉ LUIZ C. CANTO, FRANK RAYNNER V. RIBEIRO
Abstract
A new species of Knodus is described from the rio Cupari drainage, a tributary from the right margin of the lower rio Tapajós, Pará State, Brazil. The new species differs from its congeners, except K. geryi, by having a dark basal blotch on each caudal fin lobe (vs. caudal fin lobes with sparse chromatophores, lacking basal blotches) and, with the exception of K. borki, K. heteresthes, and K. pasco, by having 10–12 scales around the caudal peduncle (vs. 13–15).

Keywords
Pisces, Amazon basin, biodiversity, Knodus geryi, Stevardiinae, taxonomy

Full Text:
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DOI: http://dx.doi.org/10.11646/zootaxa.4747.3.10

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Redescription of Lepadichthys coccinotaenia Regan 1921 and description of Lepadichthys trishula sp. nov. from southern Japan (Gobiesocidae: Diademichthyinae)
Ichthyological Research (2020)Cite this article
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AbstractLepadichthys coccinotaenia Regan 1921 (Gobiesocidae: Diademichthyinae) is redescribed on the basis of 60 specimens, including the holotype, and a new species of Lepadichthys, previously misidentified as L. coccinotaenia, described from Japan. Lepadichthys trishula sp. nov. is characterized by the following combination of characters: 10–12 (modally 11) dorsal-fin rays; 9–11 (10) anal-fin rays; 23–26 (23) pectoral-fin rays; upper end of gill membrane level with base of 8th to 10th (usually 10th) pectoral-fin ray in lateral view; 6–8 (7) gill rakers on each arch; 32 or 33 (32) vertebrae; snout somewhat short and slender, its length and depth 7.4–9.4 (mean 8.4) and 4.0–6.5 (5.1) % SL, respectively; upper jaw not sharply pointed or projected, its length 5.5–7.7 (6.5) % SL; side of lower-jaw teeth with hook-like tips; head depth 7.2–10.4 (8.5) % SL; disc size moderate, its length 14.0–18.2 (16.8) % SL; dorsal and anal fins with weak membranous connections to caudal fin; head sensory canal pores well developed, including 2 nasal, lacrimal and postorbital, and 3 preopercular pores; and three narrow white stripes from snout to vertical through posterior margin of disc, including two lateral and one on the dorsal midline. The new species is currently known only from Japan, whereas L. coccinotaenia occurs only in the southwestern Indian Ocean.

Lepadichthys trishula

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Channa aristonei a new species

UK Government papers relating to Import & export of Ornamental fishes can be found at:- www.gov.uk/government/publications/fish-health-certificates​==========================

UK Government papers relating to Import & export of Ornamental fishes can be found at:- www.gov.uk/government/publications/fish-health-certificates
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