A new cave‐dwelling loach,Triplophysa xichouensis sp. nov. (Teleostei Nemacheilidae) from Yunnan,China

A new cave‐dwelling loach of the genus Triplophysa, T. xichouensis, is described from an outlet of a subterranean river in Xisa Town, Xichou County, Yunnan Province, China. It can be distinguished from its congeners by the following characters: dorsal‐fin rays iii, 8; anal‐fin rays ii, 6; pectoral‐fin rays i, 9 or 10; pelvic‐fin rays i, 5 or 6; branched caudal‐fin rays 16(8+8); eyes highly degenerated to a very tiny black dot; dorsal‐fin origin closer to snout tip than to caudal‐fin base and anterior to vertical line of pelvic‐fin origin; pectoral fin length about two‐thirds the distance between pectoral‐fin origin to pelvic‐fin origin; caudal peduncle slender, its length about three times its depth; caudal fin emarginate; body smooth and scaleless; lateral line complete and straight; anterior chamber of air bladder wrapped in dumbbell‐shaped bony capsule and the posterior one well developed, long, oval; intestine short, bending in zigzag shape behind stomach. A key for the cave‐dwelling species of Triplophysa is provided. urn:lsid:zoobank.org:pub:9162FFB1‐7911‐47C3‐AE50‐6A00E9590327     

Description of a new cryptic,shallow‐water tonguefish (Pleuronectiformes: Cynoglossidae: Symphurus) from the western North Pacific Ocean

Combined results based on morphological characters and analyses of partial sequences of the 16s rRNA and coI genes confirm the validity of a new, cryptic, symphurine tonguefish from the western North Pacific Ocean. Symphurus leucochilus n. sp., a diminutive species reaching sizes to c. 67 mm standard length, is described from nine specimens that were collected from fish‐landing ports and from trawls made at c. 150 m off Taiwan and Japan. Symphurus leucochilus shares many similar features with those of Symphurus microrhynchus and that of several undescribed species that are morphologically similar to S. microrhynchus. Symphurus leucochilus has also been misidentified as Symphurus orientalis in fish collections because of shared similarities in some aspects of their morphology. The new species differs from all congeners by the following combination of meristic, morphological and pigmentation features: a predominant 1–2–2–2–2 pattern of interdigitation of proximal dorsal‐fin pterygiophores and neural spines; 12 caudal‐fin rays; 89–92 dorsal‐fin rays; 76–80 anal‐fin rays; 49–51 total vertebrae; four hypurals; 75–83 longitudinal scale rows; 32–35 transverse scales; 15–17 scale rows on the head posterior to the lower orbit; absence of a fleshy ridge on the ocular‐side lower jaw and a membranous connection between the anterior nostril and lower part of the eye; a narrow interorbital space and dorsal‐fin origin anterior to the vertical through the anterior margin of the upper eye; absence of both dermal spots at bases of anterior dorsal‐fin rays and melanophores on the isthmus; uniformly yellow to light‐brown ocular‐side colouration without bands; dorsal and anal fins with alternating series of dark rectangular blotches and unpigmented areas; a uniform white blind side and a bluish‐black peritoneum. Despite overall similarities in morphology between S. leucochilus and S. orientalis, as well as between two of the nominal species morphologically similar to S. microrhynchus, analyses of partial 16s rRNA and coI gene sequences show that S. leucochilus, S. orientalis and the two other nominal species represent three distinct lineages within the genus Symphurus.     

A New Trichomycterus (Siluriformes: Trichomycteridae) from Aguarague National Park of the Bolivian Preandean Region, with Comments on Relationships within of the Genus

Synopsis The Andean and preandean regions are characterized by the presence of several endorheic drainage basins, each of which has evolved a characteristic fish fauna, some of which are poorly known or hitherto inaccessible. We describe here a new species of Trichomycterus from Aguarague National Park, Bolivia. Trichomycterus aguarague is considered to belong to a species assemblage comprised of T. alterus, T. boylei, T. ramosus, and T. belensis, a group diagnosed by three putative apomorphic conditions: (1) base of the maxillary barbel wide and engrossed like a skin flap or fold, (2) premaxillary bone smaller than maxilla, and (3) odontodes embedded in thick integument that covers interopercle. Alternatively, T. aguarague and T. alterus share an unusual number of five or fewer abdominal vertebrae, which is a synapomorphy for the group composed of Scleronema, Ituglanis, and the Stegophilinae+Tridentinae+Vandelliinae+Glanapteryginae+Sarcoglanidinae clade. The new species differs from all congeners in having the following combination of characters: caudal peduncle depth 13.5 – 16.0% SL, 15 or 16 pairs of ribs, 15 dorsal procurrent rays, 12 ventral procurrent rays, 8 pectoral fin rays; 9 anal fin rays; barbels and skin of trunk with numerous, minute thread-like papillae.     

Balitora eddsi,a new species of hillstream loach (Ostariophysi: Balitoridae) from Nepal

A new species of hillstream loach Balitora eddsi is described from the Karnali River drainage in south‐western Nepal. The new species is distinguished from all its congeners by possessing the following combination of characters: six to seven unbranched pectoral‐fin rays, pelvic‐fin length 12–14% standard length (L_S), dorsal surface without circular or irregular shaped dark blotches, snout pointed, median lobe between anterior rostral barbels pointed posteriorly, dorsal‐fin origin posterior to pelvic‐fin origin, lateral line scales 66–67, caudal peduncle length 22–23·2% L_S, caudal peduncle depth 4·1–4·2 times its length.     

Knodus dorsomaculatus (Characiformes: Characidae), a new species from Teles Pires River,Tapajós River basin,Brazil

Knodus dorsomaculatus, a new species, is described from Teles Pires River, a tributary of the Tapajós River, Brazil. It can be distinguished from its congeners by the presence of a conspicuous dark blotch on the base of the first five branched dorsal fin rays and the presence of ii,9 dorsal fin rays. Additional comparisons between K. dorsomaculatus and its congeners are presented.     

A new Myleus species (Characiformes: Serrasalmidae) from the Rio Tapajós basin,Brazil

Myleus pachyodus, a new serrasalmid species, is described from the Rio Teles Pires and Rio Jamanxim, both tributaries of the Rio Tapajós in Mato Grosso and Pará states, Brazil. The new species differs from all congeners by having a remarkable ontogenetic thickening of the teeth shifting from slender incisiform in juveniles to thick bulky teeth at standard length ≥ 100 mm, whereas congeners present slender, antero‐posteriorly flat teeth throughout all life stages. The new species further differs from congeners by having 18–20 branched dorsal‐fin rays, by the lack of a diastema between contralateral outer series of premaxillary teeth and by the presence of 16–25 prepelvic spines, with the anteriormost spine never reaching the vertical through the pectoral‐fin origin.     

Hyphessobrycon platyodus (Teleostei: Characiformes), a new species from the Rio Madeira basin,Brazil, with comments on how multicuspid teeth relate to feeding habits in Characidae

A new species of Hyphessobrycon is described from the Rio Juma, a tributary of the lower Rio Aripuanã–Rio Madeira basin, Amazonas, Brazil. Hyphessobrycon platyodus can be distinguished from its congeners by the: presence of an elongated dorsal fin in adult males, 25–28 branched anal‐fin rays and absence of dark blotches from the dorsal fin and caudal peduncle. The presence of multicuspid teeth in species of Characidae and its relation with feeding habits are briefly commented on.     

Redescription and range extension of the endangered Paiva's blenny Lupinoblennius paivai (Perciformes: Blenniidae)

The Paiva's blenny Lupinoblennius paivai is redescribed and its range redefined along the Brazilian coast. It differs from its congeners by the presence of three cephalic pores between the dorsal‐fin base and lateral line, dorsal‐fin elements XII, 12, anal‐fin elements II, 16, pectoral‐fin rays 14 and 10 + 20 vertebrae. It is here reported from Amazon estuaries (Marajó and Mosqueiro islands, Pará State), increasing its range by c. 3000 km. Lupinoblennius paivai is one of the few blenniid species able to tolerate low salinities. New data about its meristics and morphometrics are presented, as well as a new habitat type.     

Moenkhausia celibela: a new species from the Amazon basin,Brazil (Characiformes: Characidae)

A new species of Characidae, Moenkhausia celibela, is described from the Rio Amazonas at Santarém, Rio Maraú, several localities in the Rio Tapajós, Rio Curuá‐Una, Rio Xingu and Rio Jari, all from the Amazon basin, Brazil. The new species is distinguished from its congeners, except species included in Géry's 1992 Moenkhausia lepidura group, by presenting a dark blotch on the upper caudal‐fin lobe, and the lower lobe is hyaline or light grey. Moenkhausia celibela is distinguished from the species of the M. lepidura group by the absence of a humeral spot and the presence of a roughly triangular and dark spot at the caudal‐fin base, extending posteriorly along the middle caudal‐fin rays, and distinctly separate from the spot on the upper caudal‐fin lobe.     

A new species of Sturisoma Swainson, 1838 (Loricariidae: Loricariinae), from the Madeira River basin,with a discussion of historical biogeography of western Amazonas and Paraguay River basins

A new loricariin species of Sturisoma is described from the Cautário, Guaporé, Mamoré, Machado and Soteiro rivers, Madeira River basin, in Bolivia and Brazil. The new species is distinguished from its congeners by the presence of a middorsal longitudinal, thin dark brown stripe on the caudal peduncle, extending from two or three plates posterior to the dorsal-fin base, reaching the origin of the caudal fin, or one or two plates anterior to the origin of the caudal fin; small squarish anteriormost abdominal plates; and a middorsal longitudinal dark-brown stripe from first predorsal plate to near the dorsal-fin origin. Furthermore, the new species is diagnosed from congeners by plate morphology, counts on the median series, coalescent plates and ventrolateral thoracic plates, in addition to measurements related to body and head structures. An analysis of genetic distances using cytochrome C oxidase subunit 1 gene marker of the mitochondrial genome between the new species and several congeners is presented, in addition to a likelihood analysis to illustrate the position of the new taxon within Sturisoma. An identification key for species of the genus currently recorded at the upper Amazonas River basin is provided.     

Jenynsia lineata species complex,revision and new species description (Cyprinodontiformes: Anablepidae)

The Jenynsia lineata species complex comprises J. lineata from Montevideo, Uruguay and Jenynsia multidentata, from coastal basins of Brazil, Uruguay and Argentina up to 1200 m a.s.l. Taxonomic divisions within this group were tested using three different species delimitation methods, which found the two existing names to be synonyms and revealed a new cryptic species. Jenynsia darwini sp. nov. is distinguished from all congeners by having a unique combination of character states, including the shape of the dorsal postcleithrum (three times higher than wide v. less than two times higher than wide) and female colour pattern in the half of the caudal peduncle with rows of chromatophores segmented in unaligned spots (v. aligned spots forming lines). The new species also differs from J. lineata by having 26 nucleotide substitutions in the mitochondrial gene cytochrome c oxidase I (coI). Phylogenetic analysis of the genus based on morphological characters proposed by previous studies corroborates monophyly of the subgenera Plesiojenynsia and Jenynsia, with the new species being allocated to the subgenus Jenynsia as the sister group of J. lineata.     

<Emphasis Type="Italic">Paracobitis nanpanjiangensis,</Emphasis> a new loach (Balitoridae: Nemacheilinae) from Yunnan,China

A new species of the genus Paracobitis, Paracobitis nanpanjiangensis is described from tributaries of the Nanpanjiang River drainage in China. It is distinguished from its congeners, except P. oligolepis and P. wujiangensis, by body scaleless or with rudimentary scales (caudal peduncle with several deeply embedded scales). It can be differentiated from P. wujiangensis by the complete lateral line (vs. incomplete), lower dorsal crest reaching the vertical of origin of anal fin (vs. shorter and higher dorsal crest not reaching the base of anal fin). It is distinguished from P. oligolepis by the following characters: branched dorsal fin with 81/2 (a few 91/2) rays (vs. 91/2), interspaces between bars in front of dorsal fin conspicuously thinner than those behind (vs. vermiform markings), dorsal head without vermiform markings or obscure (vs. clearly vermiform markings on dorsal head), vertebrae 4 + 36–38 (vs. 4 + 39–41).     

A new species of Hemibrycon (Characiformes,Characidae, Stevardiinae) from the upper Magdalena River basin in Colombia

Hemibrycon iqueima sp. nov., is described from small streams in the Magdalena drainage at the foothills of the western slope of the Eastern Cordillera of the Colombian Andes, Suarez municipality, Tolima Department, Colombia. The new species is distinguished from its congeners in the Magdalena–Cauca River basin by a combination of characters related to snout–anal‐fin origin length, head length, dorsal–pectoral fin distance, dorsal‐fin–hypural distance, postorbital distance, orbital diameter, snout length, number of total vertebrae, pre‐dorsal scales, scale rows between anal‐fin origin and lateral line, number of branched rays of the anal fin, maxillary teeth number and number and arrangement of hooks on the branched rays of the pectoral and dorsal fins. In addition, the validity of this species is supported by previous molecular analyses that included specimens of the new species that had been erroneously identified. Phylogenetic relationships between the new species and congeners from Pacific coast basins are discussed.     

Pethia sanjaymoluri,a new species of barb (Teleostei: Cyprinidae) from the northern Western Ghats,India

Pethia sanjaymoluri, a new cyprinid, is described from the Pavana and Nira tributaries of Bhima River, Krishna drainage, Maharashtra, India. It can be distinguished from congeners by a combination of characteristics that includes an incomplete lateral line, absence of barbels, upper lip thick and fleshy, 23–25 lateral series scales, 7–12 lateral‐line pored scales, 10 predorsal scales, 11–14 prepelvic scales, 17–20 pre‐anal scales, 4½ scales between dorsal‐fin origin and lateral line, four scales between lateral line and pelvic‐fin origin, 8–15 pairs of serrae on distal half of dorsal‐fin spine, 12–14 branched pectoral‐fin rays, 4 + 26 total vertebrae, 4 + 5 predorsal vertebrae, 4 + 13 abdominal vertebrae, 13 caudal vertebrae and a unique colour pattern comprising a humeral spot positioned below the lateral line and encompassing the third and fourth lateral‐line scales and one scale below, one caudal spot on 17th–21st lateral‐line scales with a yellow hue on its anterior side and apical half of dorsal fin studded with melanophores making the fin tip appear black. Genetic analysis based on the mitochondrial cytochrome b gene sequence suggests that the species is distinct from other known species of Pethia for which data are available.     

A new species of anglerfish (Lophiidae: <Emphasis Type="Italic">Lophiodes</Emphasis>) from the western Pacific

Lophiodes endoi sp. nov. is described from the western Pacific Ocean. Within the genus Lophiodes, the new species belongs in the L. mutilus group mainly defined by the absence of the fourth dorsal fin spine and differs from other species in the L. mutilus group in having a rounded esca with a paler tip, a third dorsal spine bearing a pair of black tendrils at two-thirds its length, 20–21 pectoral fin rays, a relatively short head, a relatively short illicium, a relatively short third dorsal spine, and a relatively long fifth dorsal spine, reaching the third soft dorsal fin ray when folded back. Comments on a similar species, L. bruchius, newly collected from the Kyushu–Palau Ridge, and notes on the distribution of congeneric species in the northwestern Pacific are provided.     

Description of a new species of Triplophysa (Teleostei: Nemacheilidae) from Guizhou Province,China

A new cave‐dwelling fish species Triplophysa guizhouensis is described based on specimens collected from Guizhou, China, in a subterranean system interconnected with the Hongshui River drainage. The species can be distinguished from its congeners by a combination of characters: eyes present; caudal fin with 14 branched rays; inner gill rakers of first gill arch 8–10; posterior chamber of air bladder developed; and body posterior of dorsal fin scaled. A key to species of Triplophysa in the Pearl River basin is provided.     

A new species of Astyanax (Characiformes: Characidae) from Costa Rica and Panama,with a key to the lower Central American species of the genus

Astyanax anai, a new species of characid fish, is described from the Sixaola River basin, eastern Costa Rica–western Panama, Central America. The new species can be distinguished from all other congeners by the following combination of characters: premaxillary teeth 4–5 at the inner series and 4–6 at the outer series; maxillary teeth tricuspid, 2–4; predorsal scale series irregular and incomplete, with an unscaled space behind tip of supraoccipital process and 12–14 scales; lateral line scales 34–39; humeral region with a conspicuous black and rounded to horizontally ovate spot and two diffuse brown and vertically elongate bars (the first through the rounded to horizontally ovate spot, the second 2–4 scales behind the first); body depth 36·6–42·3% of standard length (L_S); midlateral stripe formed by a series of 10–14 anteriorly‐directed dermal herringbone, or chevron‐shaped, marks, most apparent in juveniles and in preserved specimens, extending above the lateral line from the black humeral spot or just behind it (from the second vertical bar) to the caudal peduncle; scale rows from lateral line to base of first dorsal‐fin ray 8–9; scale rows from lateral line to base of pelvic fin 7–8; pre‐anal distance 53·9–61·9% of L_S; total anal‐fin elements 29–33; caudal spot elongated, rhomboid or rectangular, with its anterior margin surpassing the middle of the caudal peduncle, usually reaching the anal‐fin insertion, posteriorly covering 4–7 principal caudal‐fin rays and not extending onto the ventral and dorsal margins of the caudal peduncle, covering 3–5 horizontal scale rows. In order to test the phylogenetic relationships of the new taxon in relation to the other North and Central American species of the genus, a new phylogenetic hypothesis based on a reanalysis of the morphological matrix by Schmitter‐Soto (2016) is proposed. A key to the lower Central American (southern Nicaragua to eastern Panama) species of Astyanax is also provided.     

Systematic revision of the formerly monotypic genus Tanganikallabes (Siluriformes: Clariidae)

The monotypic genus Tanganikallabes, endemic to Lake Tanganyika, is a poorly known member of the family Clariidae. Examination of 142 specimens housed in museum collections has revealed the presence of at least two additional species in this genus. Tanganikallabes alboperca sp. nov. is distinguished from all congeners by the length of its pelvic fins, the presence of a depigmented vertical bar on the opercular margin, and a combination of additional morphometric (pectoral spine length, preanal length, body depth at anus) and meristic (dorsal and anal fin ray counts) characters. Tanganikallabes stewarti sp. nov. is distinguished from other Tanganikallabes species by having a relatively shorter, incomplete lateral line, and shallow body depth at the anus, as well as shorter prepelvic and preanal lengths, and a longer anal fin with a higher number of fin rays. Several morphological characters, as well as genetic data from cytochrome b (mitochondrial DNA) and 18S–ITS1–5.8S–ITS2–28S (ribosomal DNA), indicate that Tanganikallabes constitutes a monophyletic group within the Clariidae and support the recognition of additional species diversity. The monophyly of Tanganikallabes, coupled with the geographical isolation of this group to a single lake satisfy the requirements for its classification as a true species flock, the latest to be described from Lake Tanganyika. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 121–142.     

A new species of Astyanax Baird & Girard (Characiformes: Characidae) from the Rio Paraguaçu basin,Chapada Diamantina,Bahia, Brazil,with comments on bony hooks on all fins

A new species of Astyanax from the Rio Paraguaçu basin, Bahia, Brazil, is described. This new species is distinguished from its congeners known to occur in Brazilian drainages by the presence of small bony hooks on all fins of mature males. Furthermore, the new species can be diagnosed by its colour pattern, which consists of a unique vertically elongated humeral blotch, a conspicuous dark drop‐shaped horizontal blotch over the caudal peduncle, tapering anteriorly and not extending to the median caudal‐fin rays, and by the absence of a conspicuous broad dark midlateral stripe. The new species differs further by having the greatest body depth just anterior to the dorsal‐fin origin, 32–35 perforated scales in the lateral line and a reduced number of branched anal‐fin rays (16–20). Apparently, the new species does not fit into any species complex of Astyanax. The occurrence of bony hooks on all fins of Astyanax is discussed.