Supplementary description and ontogenetic variability of Coryphaenoides affinis: rediscovery of the species after 145 years since its original description (Teleostei: Gadiformes: Macrouridae).

A large adult (138 mm head length) of the grenadier genus Coryphaenoides is described. It is identified as C. affinis hitherto known only from two juvenile type specimens collected by HMS Challenger off Uruguay in 1876. The diagnosis of the species is revised to include the discovery of considerable ontogenetic changes in squamation. Spinulation on the body scales are reduced or lost with size, while the armament of the head scales become amplified. The larger of the syntype specimens is designated as the lectotype. All three known specimens of C. affinis were collected in the southwestern Atlantic at depths between 3500 and 4000 m. A key for identification for the species of the subgenus Nematonurus is provided.

A new species of Bathysphyraenops from the Indian Ocean with comments on the genus (Teleostei: Acropomatiformes: Howellidae).

A new species, Bathysphyraenops radhae, is described from the equatorial western Indian Ocean. It resembles Bathysphyraenops declivifrons in the shape of snout and number of pseudobranchial filaments in adults but can be readily distinguished from all known members of Howellidae by its characteristically armed preopercle and in strong reduction or absence of spinules on scales around the pectoral fin. The genus Bathysphyraenops is rediagnosed, and the characteristics useful in diagnosing the howellid genera are briefly discussed. The nominal genus Schistoperca is synonymized with Bathysphyraenops. A key to the species of Bathysphyraenops is provided.

Stone loaches of Choman River system, Kurdistan, Iran (Teleostei: Cypriniformes: Nemacheilidae).

For the first time, we present data on species composition and distributions of nemacheilid loaches in the Choman River basin of Kurdistan province, Iran. Two genera and four species are recorded from the area, of which three species are new for science: Oxynoemacheilus kurdistanicus, O. zagrosensis, O. chomanicus spp. nov., and Turcinoemacheilus kosswigi Ban. et Nalb. Detailed and illustrated morphological descriptions and univariate and multivariate analysis of morphometric and meristic features are for each of these species. Forty morphometric and eleven meristic characters were used in multivariate analysis to select characters that could discriminate between the four loach species. Discriminant Function Analysis revealed that sixteen morphometric measures and five meristic characters have the most variability between the loach species. The dendrograms based on cluster analysis of Mahalanobis distances of morphometrics and a combination of both characters confirmed two distinct groups: Oxynoemacheilus spp. and T. kosswigi. Within Oxynoemacheilus, O. zagrosensis and O. chomanicus are more similar to one other rather to either is to O. kurdistanicus.

New specimens and supplementary descriptions of two rare dragonfishes, Photonectes klepadloae and P. litvinovi, with comments on the distribution of P. filipendulus (Teleostei: Stomiidae: Melanostomiinae).

Supplementary descriptions based on new specimens of two rare dragonfish species, Photonectes klepadloae and P. litvinovi, formerly known by the holotypes only, are presented. The presence of a bulbous swelling at the tip of the terminal filament of the mental barbel is documented for P. klepadloae, and its absence in some specimens of that species, including the holotype, is likely an artifact of preservation. The presence of blue luminous tissue is documented for P. litvinovi, which was formerly believed to lack it due to skin abrasion in the holotype. A key for the species is corrected based on the new diagnostic characters of P. litvinovi. Incorrect mapping of the distribution of P. filipendulus provided in the original description is improved and a map showing the known distribution of all three aforementioned species is presented.

A new Coelorinchus from the western Indian Ocean with comments on the C. tokiensis group of species (Teleostei: Gadiformes: Macrouridae).

A new species, Coelorinchus zinjianus sp. nov., is described from the western Indian Ocean off Madagascar. In many respects, the new species is similar to C. quadricristatus but differs from that species in details of scale spinulation, mouth coloration (pale vs. dark), size of external light organ, and some other proportions. Together with C. flabellispinis and C. trunovi, these species form the flabellispinis species group, which is restricted to the northern and western Indian Ocean and is similar in most respects to the West-Pacific tokiensis group, but differs in the size and shape of the terminal snout scute (long and pointed, diamond-shaped vs. small and blunt) and apparently attaining a smaller adult size (< 45-55 cm TL vs. > 80-90 cm TL, depending on the species).

New species and records of Maechidius Macleay, 1819 from New Guinea (Coleoptera: Scarabaeidae: Melolonthinae).

Seven species of Maechidius Macleay, 1819 from New Guinea are described, namely M. addarcis Prokofiev, new species, M. astrolabius Prokofiev, new species, M. bombycinus Prokofiev, new species, M. echinoides Prokofiev, new species, M. macrosoma Prokofiev, new species, M. penicilliger Prokofiev, new species, and M. telnovi Prokofiev, new species. Males of M. interruptocarinulatus Heller, 1914 and aedeagus of M. seriepunctatus Moser, 1920 are described for the first time. Key to the Indonesian and New Guinean species is amended for inclusion of the newly described species.

A new species of the grenadier genus Coelorinchus (Gadiformes: Macrouridae) from the western Indian Ocean.

A new species, Coelorinchus tricristiger sp. nov., is described from the western Indian Ocean off Socotra and Somalia. It belongs to the Coelorinchus hubbsi group of the subgenus Quincuncia. The modified scales on top of the postorbital portion of head forming a prolonged longitudinal ridge, in combination with its distinctive body markings and the absence of a ventral projection of subopercle, make the new species easily distinguishable from congeners. This is the second representative of the C. hubbsi group in the western Indian Ocean in addition to the previously known C. melanosagmatus.

A new species of the grenadier genus Coelorinchus from the seamounts in the southeastern Atlantic Ocean, with redefinition of C. vityazae (Teleostei: Gadiformes: Macrouridae).

Re-investigation of the grenadier Coelorinchus vityazae endemic to the West Wind Drift Islands Province reveals species-level differences between the populations from the southeastern Atlantic and southwestern Indian oceans. The southeastern Atlantic populations (from Discovery and Gough seamounts) are described as a new species, C. inventionis sp. nov., characterized by a moderately short snout (27.7-33.9 % HL, vs. 32.0-38.7 % in C. vityazae) tipped with short, weakly tripartite terminal scute (vs. triangular and sharply pointed); uniformly thick, unpigmented lips (vs. fleshy, partly blackish upper lip with lateral portions expanded at middle in C. vityazae); modally i+17 or i+18 pectoral-fin rays (vs. i+15 or i+16), and anal-fin rays conspicuously darkened distally (vs. uniformly and finely peppered). Statistically significant differences between these two species were found for 28 of 39 morphometric characters. The Discovery and Gough specimens show a drastic difference in size of the light organ, which may reflect an initial stage of speciation within C. inventionis sp. nov. Iwamoto & Graham's (2008) key to the species of the C. fasciatus group is modified for inclusion of the new species.

A new species of Lepidotrigla from the South China Sea off Vietnam (Teleostei: Scorpaeniformes: Triglidae).

A new species of the gurnard genus Lepidotrigla is described from the South China Sea off southernmost central Vietnam. Lepidotrigra firmisquamis sp. nov. is most similar to L. alata and L. marisinensis and co-occurs with L. marisinensis in the Bays of Nha Trang and Van Phong, but can be easily distinguished from both species by the well developed preocular spines and postorbital groove and by a slightly lower lateral-line scale count (54-58 instead of 58-64). A comparison with all Lepidotrigla species known from the South China Sea is presented.

A new deep-bodied species of Antigonia (Teleostei, Antigoniidae) from the Andaman Sea (northeastern Indian Ocean).

A new species of boarfish, Antigonia emanuela, is described from two specimens collected in the Andaman Sea off the coast of Myanmar during bottom trawl surveys conducted by the R/V Dr Fridtjof Nansen in 2015 and 2018. It is unique within the genus in the combination of the deeply rhomboid body (1.1-1.2 times deeper than long), nine dorsal-fin spines, premaxilla strongly bent in middle, scales with deep apical crest armed with numerous spinules, soft dorsal, anal and caudal fins bright-yellow in life. Two other Antigonia species captured during these surveys are A. indica and A. ovalis, the latter species being a first report for the Andaman Sea.

Two new species of Photonectes with blue luminous tissue on body, and a re-examination of P. mirabilis (Teleostei: Stomiidae).

Two new species of the mesopelagic genus Photonectes are described from the Pacific Ocean. Both of them are characterized by the presence of blue luminous tissue on the body. Photonectes cyanogrammicus new species, is characterized by the unique shape of the mental barbel, expanded distally and lacking bulbs or appendages. It is presently known only from the holotype collected in the Solomon Sea. Photonectes sphaerolampas new species, is described from four specimens collected in the western and central Pacific. It can be easily distinguished from the other species by the presence of the large spherical bulb of the mental barbel with darkly pigmented terminal appendage, split at its tip into several short filaments. Photonectes mirabilis Parr, 1927 is re-described, based on four specimens from the Atlantic and Pacific Oceans; details of jaw dentition and arrangement of the luminous tissue for this species are specified. A key for identification of the species of Photonectes with blue luminous tissue on the body is provided.

First Record of the Ceratioid Anglerfish Species Gigantactis microdontis (Teleostei: Lophiiformes: Gigantactinidae) in the Western Pacific Ocean.

The rare ceratioid anglerfish Gigantactis microdontis was formerly known from 12 specimens collected in the Eastern Pacific from 158° W eastward: off Hawaiian Islands, Oregon, California and Peru. Thirteenth specimen reported herein extends the known distribution of this species some 7630 km westward into the western tropical Pacific (off Caroline Islands). The newly reported specimen shows no principal differences in morphology from the previously known individuals.

A new species of Barbatula from the headwaters of the Bulgan River in western Mongolia (Teleostei: Nemacheilidae).

Barbatula karabanowi, new species, is described from the upper Bulgan River drainage in Mongolia. It is most similar to B. dsapchynensis from the Zavhan River basin (Lake Valley, Mongolia). The new species is distinguished from this and all other species of Barbatula in Asia by a combination of characters, none of them unique: nostrils widely spaced; snout broad, ratio between maximum head width and width of snout at anterior nare 1.4-1.6; lips smooth, upper lip with a short incision; lower lip with short, well developed lateral lobes, mental lobes oval, lacking conical protrusions; scales absent or isolated scales present on the flank between dorsal- and caudal-fin bases; 42-44 vertebrae (usually 43); 75-88 lateral line pores on flank; paired fins with rounded tips; pigmentation pattern with densely set and partially fused irregularly shaped blotches and streaks. Barbatula karabanowi occurs in syntopy with B. cf. altayensis. It is distinguished from this species by having widely separated nares (vs. closely-set), details in the mouth structure, few or no scales (vs. squamation well developed), less vertebrae and lateral line pores (42-44 and 75-88 vs. 44-45 and 89-105, respectively), "non-muscular" cheeks in both sexes (vs. thickened, especially in the males) and details in colour pattern. These two species were found to prey on different food items and were the only fish taxa found in the studied part of the river.

Reappraisal of Synagrops Günther, 1887 with rehabilitation and revision of Parascombrops Alcock, 1889 including description of seven new species and two new genera (Perciformes: Acropomatidae).

An ongoing review of the fishes of the basal percoid family Acropomatidae has revealed that the genus Synagrops Günther, 1887 as it is currently understood is not a natural group. Species with a serrated pelvic-fin spine are here placed in the resurrected genus Parascombrops Alcock, 1889 (type-species: Parascombrops pellucidus Alcock, 1889), and the new, monospecific genus Caraibops n. gen. (type-species: Synagrops trispinosus Mochizuki & Sano, 1984). Parascombrops is unique amongst Acropomatidae in the combination of the presence of vacant 8th interneural space, a predorsal formula /0+0/0+2/ and an epaxialis attachment type 1. Caraibops n. gen. shares none of these characters and further differs from Parascombrops by an anal-fin formula of III + 9 (vs II + 7 or III + 6), and the absence of denticles on the ectopterygoid. Parascombrops is revised and now contains a total of 13 species, including 7 new: P. analis (Katayama, 1957), P. argyreus (Gilbert & Cramer, 1897), P. glossodon n. sp., P. madagascariensis n. sp., P. mochizukii n. sp., P. nakayamai n. sp., P. ohei n. sp., P. parvidens n. sp., P. pellucidus Alcock, 1889, P. philippinensis (Günther, 1880), P. serratospinosus (Smith & Radcliffe, 1912), P. spinosus (Schultz, 1940) and P. yamanouei n. sp. Synagrops adeni Kotthaus, 1970 and S. malayanus Weber, 1913 are treated as synonyms of P. pellucidus and P. philippinensis, respectively. Lectotypes are designated for P. philippinensis and S. malayanus. The main characters used to distinguish between the species of Parascombrops are: serration of other fin spines, number of gill rakers and pseudobranchial filaments, head profile, presence or absence of ridges on the preopercle, shape of 1st anal-fin pterygiophore, dentition on vomer, palatines and ectopterygoids, orbit diameter, pectoral-fin length, maximal body depth and otolith morphology. The genus Synagrops is here confined to two species, S. japonicus (Döderlein, 1883) and S. bellus (Goode & Bean, 1896), characterized by the apomorphic character of an otic capsule with a posteriorly open myodome, a basioccipital fossa and a very specialized otolith morphology. Synagrops is also characterized by the absence of pelvic-fin spine serrations. Two other species without a serrated pelvic-fin spine, originally described in Synagrops, are removed from this genus. Synagrops microlepis Norman, 1935 is separated into the monotypic Kaperangus n. gen., the only genus in the family with two supraneurals (cf. three in all other taxa). The second, Synagrops pseudomicrolepis Schultz, 1940 is re-assigned to the genus Verilus.        The geographic distribution of Parascombrops as currently composed is discussed, and is shown to be primarily of West Pacific nature, with few species in the Indian Ocean and one in the tropical West-Atlantic (P. spinosus). The West Atlantic species Parascombrops spinosus is very closely related to P. mochizukii from the tropical northwestern Pacific, and the implications of this disjunct distribution are discussed. The high degree of speciation now recognized in Parascombrops species of the West-Pacific indicates that a diverse ecological adaptation within an overall pseudoceanic habitat may have played a major role in speciation, which would have remained obscured without adequate taxonomic resolution.        Fossil, otolith-based records are also briefly discussed in the context. The extant Parascombrops argyreus and P. ohei are reported from the Pliocene of Japan, and Caraibops trispinosus has been recorded from the Pliocene of Venezuela.

A new genus and species of cardinalfish (Percomorpha, Apogonidae, Sphaeramiini) from the coastal waters of Vietnam: luminescent or not?

Xeniamia atrithorax is a diminutive new genus and new species. The following combination of melanophore patterns is unique among known apogonids: a large cluster of melanophores in the skin anterior to the insertion of the pelvic-fin base, then extending forward along the sides of the isthmus; posterior portion of the oral chamber is black with melanophores extending below the gill apparatus forward along the base of the oral chamber thence along the basibranchials ending posterior to and below the level of the tongue; a line of large melanophores extends along the inner side of the ceratohyals; black to blackish stomach; and the anterior portion of the intestine is mostly pale with few black spots becoming more densely spotted with melanophores past the first bend and black from the second intestinal turn to the anus. The peritoneum is silvery with scattered melanophores that are more densely distributed along the lower portion of the abdominal cavity. There are two pale, large pyloric caeca at the connection between the stomach and intestine. The combination of eight first-dorsal spines, two supernumerary dorsal spines, one supraneural, lacking an ossified basisphenoid, two epurals and fused hypurals 1+2, preopercle with a smooth ridge and edges, fourth dorsal spine longer than third distinguish this cardinalfish from all other genera. This new genus may be related to Jaydia in the Sphaeramiini rather than with the Ostorhinchini or Siphamiini. Possible luminescent activity is inferred from anatomy and unique melanization patterns versus suppression of light from luminescent prey in the alimentary canal. A table lists suspected and known luminescent apogonids.

A new species of Neobathyclupea from the northern Indian Ocean with comments on N. malayana (Teleostei, Perciformes, Bathyclupeidae).

A new species of Neobathyclupea is described from two specimens collected off Myanmar and off Socotra Island. The new species is most similar to N. malayana, but differs from it and other congeners in having jet-black coloured fins, larger pseudobranch, dorsal-pterygiophore pattern and some body proportions. Neobathyclupea malayana is re-diagnosed. Individual variations in armament of the preopercle and in the dorsal-pterygiophore patterns within Bathyclupeidae are discussed.

The complete mitochondrial genome of giant stone loach Triplophysa siluroides (Cypriniformes: Balitoridae).

In this study, the complete mitogenome sequence of balitorid fish, giant stone loach Triplophysa siluroides, which collected from the Yellow River, China has been sequenced by the long polymerase chain reaction method. The mitogenome, consisting of 16,574 base pairs (bp), had typical vertebrate mitochondrial gene arrangement, including 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and a noncoding control region (CR). CR of 918 bp length is located between tRNA(Pro) and tRNA(Phe). The overall base composition of Triplophysa siluroides is 28.8% for A, 28.7% for T, 25.0% for C, and 17.5% for G, with a slight AT bias of 57.5%. The complete mitochondrial genome may provide rather informative data for reconstructing and addressing new molecular perspectives for balitorid phylogenies.

The complete mitochondrial genome of altai osman Oreoleuciscus humilis Warpachowski (Cypriniformes, Cyprinidae).

The complete mitochondrial genome of altai osman Oreoleuciscus humilis Warpachowski collected from Mongolia has been amplified and sequenced in this study. The complete mitochondrial genome is 16,606 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, 1 control region (CR) and 1 light-strand replication origin (OL). The overall base composition of Oreoleuciscus humilis is 27.6% for A, 26.4% for T, 27.2% for C, 18.8% for G, with higher AT content 54.0%. This study will be rather beneficial for understanding the phylogenetic approach of Oreoleuciscus species and other related genera of cyprinid fishes.

A new species of Barbatula from the Russian Altai (Teleostei: Nemacheilidae).

Barbatula restricta, new species, is described from the Saldan-Kol Lake in the upper Ob River drainage in the Altai Mountains. It is distinguished from all other species of Barbatula in Asia by its body depth increasing continuously between the nape and the dorsal-fin origin and a combination of characters: nares widely spaced, upper lip with a short medial incision, lower lip without lateral expansions, mental lobes of lower lip without conical protrusions, tips of paired fins formed by 1st and 2nd branched rays, 42-45 (mean 44) vertebrae, color pattern consisting of small irregular mottles without saddles on back. An overview of the status of all nominal Asiatic Barbatula species described is given.