Three new species of the genus <Emphasis Type="Italic">Acropoma</Emphasis> (Perciformes: Acropomatidae) from the Indian Ocean

Three new species of Acropoma are described from the Indian Ocean. These species have been identified as “A. japonicum Günther 1859” by many authors, but clearly differ from A. japonicum in the shape and length of the luminous gland, counts of pectoral-fin rays and scales between first dorsal-fin base and lateral line, and other diagnostic characters. Acropoma heemstrai sp. nov. is described on the basis of 17 specimens (53.1–121.0 mm standard length: SL) collected from South Africa and Mozambique. It is distinguished from other congeners by its unique moderate Y-shaped luminous gland, extending from the throat to midway between the origins of the pelvic and anal fins, (luminous gland length 23.1–27.0% SL) and a pointed protrusion on the symphysis of lower jaw. Acropoma lacrima sp. nov. is described on the basis of 6 specimens (64.1–77.9 mm SL) collected from the Arabian Sea. Also, this species has been previously reported as “A. argentistigma Okamoto and Ida 2002” from the Bay of Bengal. It is characterized by having a vertical line on the cheek, short U-shaped luminous gland (luminous gland length 15.0–16.0% SL), and weakly ctenoid and cycloid scales on the side of the body. Acropoma neglectum sp. nov. is described on the basis of 5 specimens (105.3–168.5 mm standard length: SL) collected from the Gulf of Aqaba, northern Red Sea. It is similar to A. japonicum in having a short U-shaped luminous gland, but differs in having a shorter luminous gland (12.0–13.4% SL vs. 17.0–20.8% SL in A. japonicum), 3 scales between first dorsal-fin base and lateral line (vs. 4 scales in A. japonicum), and 16–17 pectoral-fin rays [vs. 14–16 (modally 15) in A. japonicum].     

Review of Indo-Pacific dwarf lionfishes (Scorpaenidae: Pteroinae) in the <Emphasis Type="Italic">Dendrochirus brachypterus</Emphasis> complex,with description of a new species from the western Indian Ocean

A taxonomic review of the Dendrochirus brachypterus complex resulted in the recognition of five species, including Dendrochirus barberi (Steindachner 1900), Dendrochirus bellus (Jordan and Hubbs 1925), Dendrochirus brachypterus (Cuvier in Cuvier and Valenciennes 1829), Dendrochirus hemprichi sp. nov. and Dendrochirus tuamotuensis Matsunuma and Motomura 2013. The complex is defined as having usually 9 dorsal-fin soft rays, usually 5 anal-fin soft rays, 17–20 (rarely 20) pectoral-fin rays, no ocellated spots on the soft-rayed portion of the dorsal fin and usually 2 (sometimes none) barbels on the snout tip. Dendrochirus barberi, known from the Hawaiian Islands and Johnston Atoll, is characterized by usually 18 pectoral-fin rays, a relatively high number of scale rows in the longitudinal series (modally 51 vs. 39–49 in other species) and mottled markings on the pectoral fin in large specimens. Dendrochirus bellus, restricted to the northwestern Pacific Ocean from the South China Sea north to southern Japan, is characterized by usually 17 pectoral-fin rays, a relatively low number of scale rows in the longitudinal series (modally 38 vs. 44–51 in other species), and the absence of skin flaps on the orbit surface and uppermost preopercular spine base. Dendrochirus tuamotuensis, recorded only from the Tuamotu Archipelago, is characterized by 19 pectoral-fin rays, the posterior margin of the pectoral fin strongly notched, and a relatively shallow and narrow head and body. Dendrochirus hemprichi sp. nov. is distributed in the western Indian Ocean, including the Red Sea. Although previously confused with a closely related congener (D. brachypterus, known from the northern and eastern Indian Ocean and western Pacific), D. hemprichi can be distinguished from the former by having fewer scale rows between the last dorsal-fin spine base and lateral line, and between the sixth dorsal-fin spine base and lateral line [4–7 (5) in D. hemprichi vs. 5–7 (6) in D. brachypterus, in both cases], a slightly greater interorbital width at the mid-orbit [5.5–10.7 (mean 7.8) % SL vs. 4.5–8.9 (6.8) % of SL] and at preocular spine base [4.4–9.1 (6.6) % SL vs. 3.5–7.8 (5.7) % of SL], and slightly shorter posteriormost (usually 13th) dorsal-fin spine length [11.8–19.9 (15.3) % SL vs. 13.3–21.3 (17.2) % of SL]. Moreover, D. hemprichi tends to have relatively more spinous points on the head spines and ridges, compared with D. brachypterus. Notwithstanding the morphological similarity between the two species, an obvious genetic difference was observed between D. hemprichi and D. brachypterus. Dendrochirus chloreus Jenkins 1903 and Dendrochirus hudsoni Jordan and Evermann 1903 were synonymized under Pterois barberi, as in some previous studies. Scorpaena koenigii Bloch 1789 was regarded as conspecific with D. brachypterus, which it predated. However, the former name should be suppressed under Reversal of Precedence.     

A new species of labrid fish <Emphasis Type="Italic">Oxycheilinus samurai</Emphasis> from the western Pacific Ocean

A new species of labrid fish Oxycheilinus samurai sp. nov. is described on the basis of five specimens from the Ryukyu Islands, Japan, and Panay Island, the Philippines. The new species is most similar to the Indo-West Pacific species Oxycheilinus orientalis in having a slender compressed body, 12 pectoral-fin rays, a blackish blotch around the anterior portion of the lateral-line anterior series, and a dark blotch basally on the membrane between the first and second dorsal-fin spines. However, O. samurai can be distinguished from O. orientalis by the following combination of characters: gill rakers 4 + 7–8; snout rounded with maximum circumference 49.8–63.5 % of standard length (SL); interorbital width 7.7–9.2 % of SL; caudal-peduncle depth 13.8–15.3 % of SL; posterior margin of caudal fin white; black or dark red area just before white posterior margin of caudal fin; poorly defined blackish blotches on inner surface of opercle in preserved specimens.     

<Emphasis Type="Italic">Abudefduf nigrimargo</Emphasis>, a new species of damselfish (Perciformes: Pomacentridae) from Taiwan

A new species of damselfish, Abudefduf nigrimargo (Pomacentridae), is described on the basis of six specimens (91.8–119.5 mm standard length; SL) from Taiwan. Although similar to A. caudobimaculatus Okada and Ikeda 1939, A. saxatilis (Linnaeus 1758), A. troschelii (Gill 1862) and A. vaigiensis (Quoy and Gaimard 1825) in having five dark bands on the lateral surface of the body with yellowish interspaces dorsally, the new species can be distinguished from the others by the following combination of characters: 18–19 (mode 19) pectoral-fin rays; 20–23 (22) tubed lateral-line scales; 7–8 (7)?+?14–16 (16)?=?21–24 (23) gill rakers; relatively greater body depth and longer pectoral-fin length [57.3–60.8% (mean 59.0%) of SL and 36.8–40.8% (38.5%) of SL, respectively]; 5 scale rows on cheek; scales on suborbit, usually continuous over basal area of lacrimal; many scales on anteroventral region of head; scale covering on preopercle and interopercle continuous; scales on dorsal and lateral body surfaces with blackish margin (indistinct in subadult), second and third black bands on body not extending dorsally onto membranes of spinous dorsal fin; anterior and upper margins of fourth black band usually level with sixth dorsal-fin soft ray base and not extending onto small scales on the dorsal-fin base, respectively; and caudal-fin base without black spots.     

Validity of <Emphasis Type="Italic">Abudefduf caudobimaculatus</Emphasis> Okada and Ikeda 1939 and synonymies of <Emphasis Type="Italic">Abudefduf vaigiensis</Emphasis> (Quoy and Gaimard 1825) (Perciformes: Pomacentridae)

Abudefduf caudobimaculatus Okada and Ikeda 1939, having long been regarded as a junior synonym of Abudefduf vaigiensis (Quoy and Gaimard 1825), is herein redescribed as a valid species on the basis of the holotype and 77 additional specimens. Abudefduf caudobimaculatus can be distinguished from A. vaigiensis in having 11–13 (modally 12) dorsal-fin soft rays, 4 scale rows above the lateral line, 2½ scale rows between the middle of the spinous portion of the dorsal-fin base and lateral line, 3–4 (4) scale rows on the cheek, scales always present on the anteroventral region of the head, eleventh and last dorsal-fin spines and pectoral-fin length 15.5–18.4%, 17.1–20.6%, and 33.5–39.9% of SL, respectively, two black spots on the caudal-fin base, anteriormost bar descending to behind the pectoral-fin base, 0–1 tubed lateral-line scales on the fourth vertical bar, and third to seventh (usually fifth or sixth) dorsal-fin soft ray base at the anterior margin of the fourth vertical bar. Synonymies of A. vaigiensis are discussed with designations of lectotypes for Glyphisodon vaigiensis and Glyphisodon rahti.     

<Emphasis Type="Italic">Erromyzon damingshanensis</Emphasis>, a new sucker loach (Teleostei: Cypriniformes: Gastromyzontidae) from the Pearl River drainage of Guangxi,China

Erromyzon damingshanensis, a new sucker loach is described from the Pearl River drainage in Guangxi, China. The new species Erromyzon damingshanensis is distinguished from the other species of the genus in having a crescentic median lobe of the rostral fold, rostral barbels shorter than rostral fold; postlabial groove broadly interrupted medially, seven branched dorsal fin rays, 16 branched pectoral fin rays, lateral line scales 88–95, caudal peduncle depth larger than its length; body with 12 irregular bars on flank, interrupted on dorsum.     

Redescription of <Emphasis Type="Italic">Lagocephalus cheesemanii</Emphasis> (Clarke 1897), a senior synonym of <Emphasis Type="Italic">Lagocephalus gloveri</Emphasis> Abe and Tabeta 1983, based on morphological and genetic comparisons (Actinopterygii: Tetraodontiformes: Tetraodontidae)

Lagocephalus gloveri Abe and Tabeta 1983 is shown to be a junior synonym of Tetrodon cheesemanii Clarke 1897 based on examination of morphological characters and DNA analysis of specimens collected from the western North Pacific, Australia and New Zealand. Lagocephalus cheesemanii is distinguished from other species of Lagocephalus by the following combination of characters: spinules on the back in a rhomboidal patch extending from the region between the nasal organ to the posterior part of the pectoral fin; caudal fin double emarginate with middle rays posteriorly produced; dorsal-fin rays 11–15; anal-fin rays 11–14; pectoral-fin rays 15–18; vertebrae 8+11=19; dorsal half of the body dark brown to brownish black; caudal fin dark brown to black with dorsal and ventral white tips. A neotype of L. cheesemanii is designated.     

New species of <Emphasis Type="Italic">Jakutoproductus</Emphasis> from the Lower Permian of Verkhoyansk Region

Two new brachiopod species of Jakutoproductus, J. lenensis sp. nov. and J. talchanensis sp. nov., are described. J. lenensis occurs in the upper part of the J. verkhoyanicus Zone of the Khorokytian Horizon (Asselian–Sakmarian deposits) of the lower reaches of the Lena River and in the Sobolokh-Mayan and Allara-Khadaryn’ya river basins. J. talchanensis is identified from the Khorokytian Horizon of the Talchan River (Baraiy River basin). A new subzone, the J. lenensis Subzone, is proposed for the upper part of the J. verkhoyanicus Zone of the Khorokytian Horizon of the Verkhoyansk Region.     

A new species of <Emphasis Type="Italic">Pempheris</Emphasis> (Perciformes: Pempheridae) endemic to the Ogasawara Islands,Japan

Pempheris familia sp. nov. is described on the basis of two specimens collected from the Ogasawara Islands, Japan. The new species is most similar to Pempheris japonica Döderlein in Steindachner and Döderlein 1883, endemic to Japanese and Korean waters, in having adherent scales with strong ctenii on the lateral and ventral surfaces of the body, each scale expanded basally and distally due to central narrowing, the abdomen with a U-shaped cross-sectional outline, a large ventral fenestra between the coracoid and cleithrum, 10 dorsal-fin soft rays and 35 or 36 anal-fin soft rays. However, Pempheris familia can be distinguished from P. japonica by the following combination of characters: 84–88 pored lateral-line scales; 14 or 15 scale rows above the lateral line; 50–55 predorsal scales; 26 circumpeduncular scales; and a distinct blackish blotch on the pectoral-fin base. Pempheris familia appears to be endemic to the Ogasawara Islands.     

Review of the <Emphasis Type="Italic">Chromis xanthura</Emphasis> species group (Perciformes: Pomacentridae), with description of a new species

A taxonomic review of the Chromis xanthura species group, defined here as having 13 dorsal-fin spines, three upper and three lower procurrent caudal-fin rays, two black bands at the preopercular and opercular margins, and a yellow caudal fin when juvenile, resulted in the recognition of three species, Chromis xanthura (Bleeker 1854), Chromis opercularis (Günther 1867), and Chromis anadema sp. nov. Chromis xanthura and C. opercularis, the Pacific and Indian Ocean paired sister species, respectively, are redescribed, with confirmation of two color types of C. xanthura (having a white or black caudal peduncle and fin) as a single species on the basis of morphological and molecular analyses. Chromis anadema sp. nov., described from the oceanic islands of the Pacific Ocean on the basis of 21 specimens, is characterized by having 28–33 gill rakers; longest dorsal-fin soft ray length 20.0–24.7% of standard length (SL); first anal-fin spine length 5.0–6.1% of SL; caudal-fin length 33.4–43.8% of SL; posterior tips of caudal-fin lobes not filamentous in adults; broad black bands along preopercular and opercular margins, sum width of two bands 28.9–38.7% of head length; distal half of soft-rayed portion of dorsal fin transparent in adults; triangular black blotches at upper and lower caudal-fin base in adults; caudal peduncle and fin bluish black in adults; and body grayish, and all fins (except for pectoral fin) bright yellow in juveniles.     

Two new species of deepwater flathead <Emphasis Type="Italic">Bembras</Emphasis> Cuvier, 1829 from the Andaman Sea,eastern Indian Ocean

Two new species of Bembras Cuvier 1829, Bembras leslieknappi sp. nov. and Bembras andamanensis sp. nov., are described from single specimens collected from the Andaman Sea off Myanmar, eastern Indian Ocean, in 2015. The two new species are distinguished from each other and five known congeners by the numbers of anal-fin rays and pectoral-fin rays (15 and 20 in B. leslieknappi vs. 14 and 20–21 in B. andamanensis), forward-slanting body scale rows above the lateral line (80 vs. 74) and upper limb gill rakers (3 vs. 4), as well as by head (41.5 vs. 42.1% SL), snout (14.3 vs. 13.8% SL) and orbit (10.4 vs. 10.9% SL) proportions, and color of the second dorsal (dusky, with blackish spots only on first spine and bases of many soft rays vs. pale, with many scattered blackish spots), pectoral (with a blotch vs. without it) and caudal (both with a broad band) fins.     

New species <Emphasis Type="Italic">Amblyeleotris</Emphasis> (Gobiidae) from Phan Thiet Bay (South China Sea,Vietnam)

A new species Amblyeleotris memnonia sp. n. from the South China Sea is described. By the high number of rays in the second dorsal and anal fins, the new species is close to A. gymnocephala and A. cephalotaenia, but it differs from them and all other species by the uniform dark color of the body.     

Aboral nervous system in two Ordovician crinoids: Reconstruction and comparison of Baltic <Emphasis Type="Italic">Pentamerocrinus</Emphasis> Jaekel and <Emphasis Type="Italic">Grammocrinus</Emphasis> Eichwald

Two unusual Middle Ordovician crinoid genera from the St. Petersburg Region, Pentamerocrinus Jaekel, 1918 and Grammocrinus Eichwald, 1860, are redescribed. A new species, Pentamerocrinus kosovi sp. nov., is described based on new material and the cup structure in the type species Grammocrinus lineatus, which has previously been known only from stem fragments, is reconstructed. The system of ridges and canals on the internal surface of the cup plates in both genera is described, allowing the reconstruction of the aboral nervous system. It is in general similar to extant crinoids, but the two Ordovician genera differ considerably in structural details. In Pentamerocrinus, ten nerve cords diverge interradially from the ganglionated nerve ring at the cup base and soon are fused in pairs inside the rays. In Grammocrinus, a similar nerve ring also gives rise to ten cords, but they are inside the rays and become fused in the interrays. This distinction in morphology of the nervous systems is correlated with the interradial arrangement of the axial canal angles of the stem in the first case and radial in the second. Therefore, despite general similarity in the structure and arrangement of calyceal plates, the genus Grammocrinus is assigned to the disparid crinoid family Iocrinidae, while the monotypic family Pentamerocrinidae Jaekel, 1918 is regarded as a fam. inc. sed. of inadunate crinoids.     

A new species of eel cods <Emphasis Type="Italic">Muraenolepis kuderskii</Emphasis> sp. nova (fam. Muraenolepididae) from South Georgia (the Scotia Sea)

A new species of the eel cod Muraenolepis kuderskii sp. nova from the Scotia Sea, South Georgia, from depths of 440–605 m is described. The species belongs to the group of “few-rayed” species having less than 150 rays in the dorsal fin and less than 114 rays in the anal fin. According to general body proportions, M. kuderskii is closely related to high-latitude Antarctic species M. trunovi; however, it differs from the latter and all other species of the group of “few-rayed” eel cods in a short chin barbel, small sizes of the eye, a short antebranchial distance, a short anteanal distance, and a long postanal distance.     

A new species of <Emphasis Type="Italic">Trichodina</Emphasis> Ehrenberg, 1830 (Ciliophora: Trichodinidae) infecting farmed <Emphasis Type="Italic">Clarias gariepinus</Emphasis> (Burchell) (Siluriformes: Clariidae) in Cuba

A new species of Trichodina Ehrenberg, 1830 collected from the skin and fins of farmed North African catfish Clarias gariepinus (Burchell) fingerlings, is described. The new species can be distinguished from other trichodinids by the characteristics of the adhesive disc, especially by the great number of denticles. Trichodina merciae n. sp. is morphologically similar to T. renicola (Mueller, 1931) and T. marplatensis Martorelli, Marcotegui & Alda, 2008, in the number of denticles, but differs in the morphometric data, denticle morphology, environment and location. Trichodina merciae n. sp. has broad sickle-shaped blades and thin, straight rays, while T. marplatensis has broad club-shaped blades and wide S-shaped rays. Besides, denticle length, blade length, ray length, width of central part and denticle span of the new species are greater than T. marplatensis. However, the diameter of denticle ring and the diameter of the central area in T. marplatensis is larger than the ones in T. merciae n. sp. This is the first record of freshwater ectoparasite trichodinid with an average number of denticles greater than 50.     

<Emphasis Type="Italic">Sebastiscus vibrantus</Emphasis>, a new species of rockfish (Sebastidae) from Indonesia and Taiwan

A new species of rockfish, Sebastiscus vibrantus, is described on the basis of 24 specimens collected from Bali, Indonesia and Taiwan. Although closely resembling Sebastiscus tertius (Barsukov and Chen 1978) in overall body appearance, and having usually 19 pectoral-fin rays and black margined white blotches scattered on the lateral body surface, the new species has thicker unbranched pectoral-fin rays, a greater pectoral-fin base length, the third dorsal-fin soft ray usually longest, the anterior margin of the scaled suborbital area not reaching level the anterior margin of the orbit, and weakly developed nuchal spines.     

<Emphasis Type="Italic">Careproctus iacchus,</Emphasis> a new variegated snailfish (Liparidae) from the Seas of Japan and Okhotsk

A new species of snailfishes, Careproctus iacchus, is described on the basis of three specimens collected from the Seas of Japan and Okhotsk. Among the species of Careproctus, the new species is most similar to Careproctus comus and Careproctus faunus, both known from the Aleutian Islands, in having a variegated body coloration. However, it can be distinguished in having 44–46 dorsal- and 39–40 anal-fin rays (vs. 50–56 and 44–50 in C. comus and 47–51 and 41–45 in C. faunus, respectively), a pectoral fin without a notch (vs. both with a shallow notch), no interradial fenestra between proximal radials two and three in the pectoral girdle (vs. both having a fenestra between proximal radials two and three), a gill slit entirely above the pectoral fin (extending to just above the pectoral fin or to 1–5th ray), a body with many white spots (vs. mottled with red and white), and a large white blotch on cheek (vs. no distinct markings on cheek) when fresh.