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.     

Description of a new perchlet,Chelidoperca formosa,from southwestern Taiwan (Peciformes: Serranidae)

A new perchlet species is described on the basis of four specimens collected from southwestern Taiwan. It is similar to congeners with relatively few lateral-line scales (35–38) and can be distinguished by having third to sixth dorsal-fin spines notably long; eighth and ninth dorsal-fin spines notably short; developed gill rakers 1 + 7–8; scale rows between lateral line and sixth dorsal-fin spine 4 (the dorsalmost half-sized); tip of upper corner of caudal fin reddish; four reddish bands midlaterally on body with groups of melanophores in these bands. DNA barcoding analysis reveals the new species is a distinct lineage and closest to Chelidoperca microdon. The average interspecific genetic distance calculated by the K2P model is 15.4%, whereas the mean distance from the new species to C. microdon is 18.3%. The inferred phylogenetic tree supports monophyly of Chelidoperca. Including the new species, six nominal species of Chelidoperca are recognized in Taiwanese waters.     

A revision of the genus Monstrillopsis Sars (Crustacea: Copepoda: Monstrilloida) with description of a new species from Chile

In the course of a comparative analysis of the species included in the copepod genus Monstrillopsis Sars, a new species of the genus was discovered. The new species, Monstrillopsis chilensis n. sp., was found in a plankton sample collected in coastal waters off central Chile in the Southeastern Pacific. The adult female is similar to females of the type species M. dubia Scott and related forms but differs from its congeners by a combination of characters including: (1) a pair of small cephalic processes present between bases of antennules; (2) deep corrugations present on proximo-lateral surface of fifth pedigerous somite; (3) exopodal lobe of fifth leg not distally elongated; and (4) endopodal lobe of fifth legs short. This is the first record of the genus in the Southeastern Pacific and the second record of any monstrilloid in Chile. A comparative analysis of the species assigned to Monstrillopsis allowed a clarification of the generic characters and limits. The most important apomorphic characters in the genus are the presence of four caudal setae and modifications of the male antennule; other potentially useful characters are the pattern of antennule segmentation and the uniform presence of a reduced inner lobe of the fifth leg. The female of Monstrilla reticulata Davis should be retained in Monstrilla, but the purportedly conspecific male is probably a Monstrillopsis. Monstrillopsis ciqroi Suárez-Morales and M. angustipes Isaac should be transferred to Monstrilla. Haemocera filogranarum Malaquin is probably a species of Monstrillopsis. Monstrillopsis zernowi is tentatively retained in this genus as an aberrant form. A key for the identification of the species of this genus is included.     

Iterative taxonomy reveals a new species of Trichomycterus Valenciennes 1832 (Siluriformes,Trichomycteridae) widespread in Rio Doce basin: a pseudocryptic of T. immaculatus

This paper reports on a new species of Trichomycterus from the Rio Doce basin. Unusually for new taxa in the genus during the past few decades, the new species is not narrowly endemic but instead widely distributed in its major drainage, the Rio Doce. The species has been collected and deposited in scientific collections for some years, but has been systematically misidentified as the more abundant Trichomycterus immaculatus or, to a lesser degree, as other morphologically similar species from south-eastern Brazil such as T. nigricans and T. pradensis. A combination of several morphological characteristics, such as vertebral number, pectoral-fin ray counts, pigmentation pattern and barcoding distance, were iteratively used and unambiguously distinguish the new species from all congeners. The present case reveals a pattern of diversity-discovery in which rare and narrowly endemic morphologically conspicuous species are discovered and described before visually inconspicuous taxa, even when the latter are more abundant and widespread. The morphological similarities among south-eastern Brazilian species with a uniform dark-grey color serve as basis for a brief discussion about the concepts of cryptic and pseudo-cryptic species in Trichomycterus and their consequences for potentially hidden diversity in the genus.     

A new species of spiny driftwood catfish Spinipterus (Siluriformes: Auchenipteridae) from the Amazon basin

An expedition to the middle Rio Purus basin uncovered a remarkable new species of the genus Spinipterus. The new species has a very distinct and conspicuous colour pattern resembling a jaguar and it is almost four times larger than Spinipterus acsi, a small specimen (32 mm L_S) from Caño Santa Rita, a right bank tributary of Río Nanay in Peru and a second specimen was reported from Rio Juruá, Amazonas State, Brazil. Although the new species is more similar in size and colour pattern to Liosomadoras, it shares the synapomorphies for Spinipterus. The new species differs from the congener by the following characters: (a) colour pattern with large black rosette-like spots over a light yellow to brown background (v. brown background with small dark blotches over the body); (b) adult body size reaching 104.5 mm L_S (v. maximum known size 37.1 mm L_S); (c) posterior process of cleithrum short, never reaching vertical through the dorsal-fin origin (v. posterior process long, surpassing vertical through the dorsal-fin origin); (d) seven soft pectoral-fin rays (v. six); (e) caudal fin truncated (v. caudal fin rounded).     

Thysanophrys papillaris, a new species of flathead from the Andaman Sea and Northern Australia (Scorpaeniformes: Platycephalidae)

A new platycephalid,Thysanophrys papillaris, is described on the basis of six specimens (78–121 mm SL) collected from the Andaman Sea and off northern Australia (Timor and Arafura Seas). This new species can be distinguished from other congeners by the following combination of characters: presence of a single short papilla on upper surface of eye, longer snout, smaller body scales. 11 second dorsal-fin rays and 12 anal-fin rays, presence of four or more suborbital spines usually, branched short iris lappet, ctenoid lateral-line scales and interopercle not extended posteroventrally.     

Triplophysa ferganaensis,a new loach species from Fergana Valley in Central Asia (Teleostei: Nemacheilidae)

Triplophysa ferganaensis sp. nov. is described from the Shakhimardan stream, a small tributary of the Syr Darya, which does not reach the river in Fergana Valley. It can be distinguished from other valid Triplophysa loaches based on the following combination of characters: body smooth and scaleless, lateral line complete, posterior chamber of air bladder degenerated, inner gill rakers 10–11 on the first-gill arch, outer gill rakers absent, vertebrae 4 + 35–36, 8 + 8 branched caudal-fin rays, caudal peduncle depth 2.1–2.7 times its length, two supratemporal pores, dorsal-fin origin closer to the caudal-fin base than to the snout tip, caudal fin emarginated and pelvic-fin tip reaching the anus. The new species can also be distinguished from its congeners based on the molecular analyses of mitochondrial cytochrome oxidase subunit I (coI) gene sequences. The phylogenetic position of this new species indicates that it is a sister taxon of Triplophysa tenuis.     

A new species of Barbine genus Sinocyclocheilus (Teleostei: Cyprinidae) from Zuojiang River drainage in Guangxi, China

A new species of the genus Sinocyclocheilus is described based on specimens collected from Zuojiang River drainage, Guangxi, China. The new species, named Sinocyclocheilus jinxiensis, is distinguished from all congeners by its vestigial eyes, short barbels, long pectoral fin, eight to nine branched dorsal-fin rays, last unbranched dorsal-fin ray soft with serrations on posterior edge of its lower part, and 38–41 lateral line scales.     

A new species of Ituglanis representing the southernmost record of the genus,with comments on phylogenetic relationships (Teleostei: Siluriformes: Trichomycteridae)

Ituglanis australis new species, is described from tributaries of the Laguna dos Patos and Río Uruguay, in Brazil and Uruguay. This represents the southernmost record of the genus and the first occurrence of a species of Ituglanis in those systems. It is distinguished from all its congeners, except Ituglanis parahybae and Ituglanis cahyensis, by its body pigmentation with three well‐defined dark brown stripes running along each flank. Ituglanis australis differs from I. parahybae and I. cahyensis in the pectoral‐ and pelvic‐fin ray counts, the pattern of the cephalic laterosensory system and the number of dorsal‐fin basal radials. The new species, as well as several other examined congeners, has the levator internus IV muscle attached to the dorsal face of the posttemporo‐supracleithrum; a condition that corroborates the inclusion of Ituglanis into a large trichomycterine clade that also includes Bullockia, Hatcheria, Scleronema and several species of Trichomycterus. Previous proposals of the affinities within Ituglanis are reviewed and, despite some advances, the phylogenetic relationships among species of the genus remain largely unknown.     

Two new species of the sisorid Genus <Emphasis Type="Italic">Oreoglanis</Emphasis> Smith from Yunnan,China (Teleostei: Sisoridae)

Synopsis Two new species of the genus Oreoglanis, O. jingdongensis and O. immaculatus are described from the Mekong and Salween River basins, respectively, of Yunnan Province, China. Oreoglanis jingdongensis can be distinguished from other Oreoglanis species by the following characters: lower lip with a distinct median notch, posterior edge smooth or with indentations; caudal fin lunate and lower lobe longer than upper lobe. Oreoglanis immaculatus can be distinguished from its congeners by the following features: lower lip with a strait median notch, posterior edge with indentations; caudal fin emarginate and lower lobe about the same length as upper lobe, having no yellow patches on sides of body below adipose fin.     

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.     

A new Amazonian species of Brachychalcinus (Characiformes: Characidae) from the Trombetas River basin,Brazil

A new species of Brachychalcinus is described from the Rio Trombetas basin, Brazil. It differs from congeners by possessing a conspicuous rounded second humeral spot. Additionally, our new species differs from Brachychalcinus nummus, B. orbicularis and B. reisi by having a higher number of branched dorsal-fin rays, and from Brachychalcinus parnaibae by having a lower head depth.     

A new cave-dwelling loach, Triplophysa macrocephala (Teleostei: Cypriniformes: Balitoridae), from Guangxi, China

A new cave-dwelling species, Triplophysa macrocephala sp. nov. is described based on specimens collected from a karst cave in Renguang village, Lihu Town, Nandan County, Guangxi Zhuang Autonomous Region, China. The new species can be distinguished from its congeners by possessing the following combination of characters: pectoral fin not reaching beyond pelvic-fin origin; caudal fin forked; body smooth or scaleless; dorsal-fin origin anterior to pelvic-fin origin, edge of dorsal fin truncate; dorsal fin with eight branched rays; anal fin with five branched rays; eye small and vestigial; lower jaw arched with a median notch; air-bladder wrapped in bony capsule, lateral enlarged, posterior chamber of air-bladder degenerated.     

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     

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.     

Review of the genusBembras Cuvier, 1829 (Scorpaeniformes: Bembridae) with description of three new species collected from Australia and Indonesia

The bembrid genusBembras Cuvier is reviewed. Five species,B. japonica Cuvier,B. adenensis Imamura & Knapp and three undescribed species, were assigned to the genus. Type species of the genus,Bembras japonica is redescribed on the basis of 36 specimens including the holotype, and three new species,B. macrolepis, B. longipinnis andB. megacephala, previously misidentified asB. japonicus, are also described on the basis of specimens collected from Australia and Indonesia.Bembras macrolepis differs from its congeners by having large body scales, a long pectoral fin with 17–19 rays and a dark blotch on slightly upper portion to middle of margin, 14–15 anal-fin rays, small head and orbit, and caudal fin with a broad vertical dark band near posterior margin.Bembras longipinnis is distinguished from other members of the genus by having a slightly long pectoral fin with 17–19 rays and lacking a small black blotch near tip of upper rays, caudal fin with a large dark spot most intense in lower lobe, 1–2 gill rakers on upper gill arch, 13–14 anal-fin rays, slightly elong ated head and small orbit.Bembras megacephala is characterized by the following combination of characters: caudal fin with several irregular narrow vertical dark bands, small orbit, pectoral fin with 19–20 rays and lacking a small black blotch near tip of upper rays, head elongate, 2–4 gill rakers on upper gill arch, 15 anal-fin rays and small body scales. A key separating the five species ofBembras is given.     

Schistura sexnubes, a new diminutive river loach from the upper Mekong basin,Yunnan Province,China (Teleostei：Cypriniformes：Nemacheilidae)

An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readily distinguishable from its congeners by the following combination of characters: 8+8 branched caudal fin rays, an incomplete lateral line, a dissociated caudal bar, a shallow caudal peduncle depth (7.6%-9.6% SL; respectively caudal peduncle 1.76-1.95 times longer than deep), a diminutive size of less than 50 mm SL, and no sexual dimorphism. A dorsocephalic pattern consisting of a black, forward directed V-shaped formation located between the nares, and a white, ovoid blotch on the upper operculum serves as an autapomorphy.     

A new species of Hyphessobrycon (Characiformes,Characidae) from the upper Rio Jequitinhonha basin,Minas Gerais,Brazil, with comments on morphological similarities with Stethaprioninae species from headwater environments

A new species of Hyphessobrycon is described from a marshland area in the headwaters of Rio Jequitinhonha basin, Minas Gerais, Brazil. The new species differs from congeners by presenting a single well-delimited conspicuous humeral blotch, rounded to vertically oval, restricted to the area dorsal to the lateral-line row of scales, without a narrower downward extension, greatest body depth anterior to dorsal-fin origin, bony processes in anal and pectoral-fin rays of males and four teeth in the inner row of the premaxillary bone. The new species presents a set of morphological features shared by some species currently assigned to Hasemania, Myxiops and to the Astyanax scabripinnis complex. Some of these features are discussed.     

<Emphasis Type="Italic">Glyptothorax dikrongensis</Emphasis>, a new species of catfish (Teleostei: Sisoridae) from Arunachal Pradesh,northeastern India

Glyptothorax dikrongensis, a new species of sisorid catfish from the Dikrong River in northeastern India, is described. Glyptothorax dikrongensis can be differentiated from all congeners, except G. indicus, G. rugimentum and G. obliquimaculatus, by the presence of an unculiferous patch on the posterior region of the lower lip, in between the inner mandibular-barbel bases, and unculiferous striae of the thoracic adhesive apparatus extending anteriorly onto the gular region. Glyptothorax dikrongensis is distinguished from G. indicus by the following combination of characters: equal distance between the posterior end of the pectoral-fin base and the pelvic-fin origin and between the pelvic-fin and the anal-fin origin (vs. distance between posterior end of pectoral-fin base and pelvic-fin origin greater than between pelvic-fin origin and anal-fin origin), and the pelvic-fin origin anterior to or almost at a vertical through the posterior end of the dorsal-fin base (vs. posterior to the dorsal-fin base). Glyptothorax dikrongensis is distinguished from G. rugimentum in lacking vertical bars on the body and caudal peduncle, and having a deeper caudal peduncle (8.4–9.2 vs. 6.1–7.6% SL) and a shorter dorsal-fin spine (10.1–11.1 vs. 15.2–18.6% SL). It is distinguished from G. obliquimaculatus in lacking dark, oblique blotches on the body, and in having a shorter dorsal-fin spine (10.1–11.1 vs. 13.4–16.4% SL).     

A new species of Curimatopsis Steindachner (Characiformes: Curimatidae) from the Rio Nhamundá, Amazon basin

A new species of Curimatopsis is described from the Rio Nhamundá, Amazon basin in northern Brazil. The new species is distinguished from congeners by the presence of a distinctive concentration of dark pigmentation over the entire lower lobe of the caudal fin, reticulate pattern of body pigmentation, lower jaw longer than and overlapping the anterior portion of the upper jaw, crescent‐shaped posterior nostril and by morphometric and meristic data. Comments on the phylogenetic position of the new species within Curimatopsis are also provided.