Sex differences in pectoral muscles but not in pectoral fins in the three‐spined stickleback Gasterosteus aculeatus

The pectoral muscle index ( I _PM)( I _PM = 100 M _PM M⁻¹, where M _PM and M are the pectoral muscle and body masses, respectively) fin‐area and fin ray length were studied over a year in male and female three‐spined stickleback Gasterosteus aculeatus from a marine population (Öresund, Sweden) kept under simulated natural light and temperature conditions. A castration‐replacement experiment was used to test androgen effects on the I _PM, fin‐area and fin ray length. Non‐breeding males were castrated or sham‐operated in winter ( i.e . the fish had low levels of androgens). Castrated control and sham‐operated fish were implanted with empty Silastic capsules and castrated groups with capsules containing the androgens testosterone or 11‐ketoandrostenedione into the abdominal cavity. The experiment was terminated after 41 days, when the controls had matured. No morphological differences were found in pectoral fins between sexes during the year, except during the peak breeding season (May), where females showed larger fin‐area and longer fin ray in length compared to males. No effects of androgens treatment or of castration on pectoral fin‐area or fin ray length was observed. Breeding and non‐breeding males showed higher I _PM compared to females. The lower I _PM in females than in males could not be explained by the larger gonads in the former alone, as a sex difference in I _PM was still present after deduction of the ovaries from the female body mass. The I _PM was higher in sham‐operated compared to castrated fish. No effects of androgens treatment on I _PM was observed.     

Growth in length and in body depth in young‐of‐the‐year perch with different predation risk

Body shape of young‐of‐the‐year (YOY) perch Perca fluviatilis , and number and size of potential predators (perch and pike Esox lucius ) were compared across five lakes in northern Sweden. Body depth and dorsal fin ray length of YOY perch differed between lakes, with high relative body depth and long dorsal fin rays found in the lakes where the number of large piscivores was the highest. The most slender fish were found in the lake where the perch population had the smallest individuals and pike occurred in very low numbers. The average body mass in YOY perch from the two lakes with highest and lowest body depth, respectively, were the same, which indicates a difference between lakes in the relation between growth in length and in depth. Both body depth and fin ray length were correlated with predation risk by pike. Fin ray length was also correlated with number of piscivorous perch. Selection for different body shapes can be caused by different biotic and abiotic factors, singly or in combination, and the results from this study indicates that predation risk is one of these factors affecting body depth and fin ray length in perch.     

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     

Two new species and a new record of the genus Sinogastromyzon (Teleostei: Balitoridae) from Yunnan, China

Two new species and a new record of Sinogastromyzon are described from Lixianjiang River of Yunnan province, China. Sinogastromyzon lixianjiangensis, new species, can be distinguished from its congeners by the following characters: pectoral fin with XIII–XIV, 15–17 rays; pelvic fin with X–XI, 10–12 rays; 60–65 lateral-line scales; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin close to anus; tip of anal fin close to caudal-fin base; anal-fin origin nearer to the caudal-fin base than to the posterior pelvic-fin base; anus nearer to anal-fin origin than to the posterior pelvic-fin base; dorsal side of the body with 9–11 black blotches. Sinogastromyzon macrostoma, new species can be distinguished from its congeners by the following characters: pectoral fin with XII–XIV, 12–15 rays; pelvic fin with VII–IX, 11–13 rays; 48–56 lateral-line scales; mouth extremely big, slightly arched; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin far beyond anus; tip of anal fin far from caudal-fin base; anal-fin origin about midway between the posterior pelvic-fin base and caudal-fin base; anus nearer to posterior pelvic-fin base than to anal-fin origin; dorsal side of the body uniformly gray, without regular blotches in formalin preserved specimen. Sinogastromyzon cf. multiocellum is firstly recorded in China.     

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.     

A new species of the genusamblyeleotris (pisces: Gobiidae) from Japan

A new shrimp-associated goby,Amblyeleotris melanocephala, is described on the basis of specimens from Okinoshima Island. Kochi Prefecture, and Okinawa Island, Okinawa Prefecture, Japan. The species is distinguished from other members of the genus by the following combination of characters: head dark brown, a few yellow spots on pectoral fin base and opercular margin, 13 second dorsal and 13 anal fin soft rays, 20 pectoral fin rays, longitudinal scales 92–101, proportional length of interpelvic connecting membrane relative to longest pelvic fin ray (CM-value) 0.46–0.55, presence of a ventral frenum, midline of nape naked, sides scaled above midpoint between preopercle and opercle.     

Two new species of chimaeroid fishes from the southwestern Pacific Ocean (Holocephali, Chimaeridae)

 Two new species of chimaeroid fishes from the family Chimaeridae are described on the basis of morphological characters. The carpenter's chimaera is a large-bodied species of Chimaera distinguished from its congeners by massive head with blunt snout; firm, nondeciduous skin; purplish color; preopercular and oral lateral line canals branching together; and pelvic claspers that are divided for the distal one third of length, purple at the base with white fleshy tips. The pale ghost shark is a species of Hydrolagus distinguished from its congeners by a dorsal fin spine that reaches to the origin of the second dorsal fin when depressed; elongate second dorsal fin not indented along its length; preopercular and oral lateral line canals sharing a common branch; long, stout caudal filament; and pale silvery-gray coloration fading to white ventrally. The pale ghost shark has long been recognized as a new species from New Zealand, and formal taxonomic recognition of this species will prove important for fishery management. Received: October 15, 2001 / Revised: May 1, 2002 / Accepted: May 29, 2002 Acknowledgments I am grateful to Peter Last, Alastair Graham (CSIRO, Dept. of Marine Research), Clive Roberts, Andrew Stewart (NMNZ, Wellington), and Mark McGrouther and Doug Hoese (AMS, Sydney), for their hospitality and support of this research. This work was funded by grants from the National Science Foundation (NSF DEB-9510735) and the National Geographic Society (no. 5414–95), and also funded in part by the New Zealand Foundation for Scientific Research and Technology, Biosystematics of NZ EEZ Fishes Project, contract MNZ603, C. Roberts, program leader.     

A new loach, Cobitis shikokuensis (Teleostei: Cobitidae), from Shikoku Island, Japan

A new species of spinous loach, Cobitis shikokuensis, is described based on 297 specimens from Shikoku Island, Japan. The new species was formerly known as the Shikoku group of Cobitis takatsuensis. It can be distinguished from other species of Cobitis and closely related genera by a combination of the following characters: dorsal fin with 6 branched soft rays; anal fin with 5 branched soft rays; one brownish streak across eye from the tip of nose, no streak on cheek; a black spot smaller than eye diameter near the dorsal corner of the caudal fin base; 3–5 small brownish speckles on ventral side of caudal peduncle; high caudal peduncle with well-developed fleshy keels on dorsal and ventral side; a lamina circularis at base of dorsal part of pectoral fin absent; first branched soft ray of pectoral fin broad in males; pectoral soft rays widely branched from the approximate midpoint; last anal fin ray with 2 elements; interorbital width 11.2–17.1% of head length.     

Hemimyzon nanensis, a new balitorid fish from the chao phraya basin, thailand

A new balitorid fish,Hemimyzon nanensis, is described from the Mae Nam Nan River basin, a tributary of the Chao Phraya River, in northern Thailand. This species is distinguishable from its congeners by the following unique combination of characters: pectoral fin with 9–11 simple and 10–12 branched, rays; pelvic fin with 3–4 (usually 3) simple and 8–9 (usually 9) branched rays; 59–63 total lateral line scales; distance between pelvic fin bases 8.1–9,6% SL.H. nanensis is the first species of the genus recorded outside China and Taiwan.     

Three new species of Bryconamericus (Ostariophysi: Characidae) from Colombia and a diagnosis for the genus

Three new fish species are described: Bryconamericus dahli from the basins of the Patia and Mira rivers; B. ichoensis from Chaparraido Creek, the upper Atrato River basin, and B. galvisi from upper Putumayo River. Bryconamericus dahli can be distinguished from other Bryconamericus species by body depth and the larger head. B. dahli is similar to B. caucanus, but can be distinguished by the number of anal fin rays, head width and maxilla. Bryconamericus ichoensis can be distinguished by its small size, absence of a spot on the caudal peduncle, and generally 27 to 30 anal fin rays. B. ichoensis may be closely related to B. multiradiatus, but can be distinguished by the number of unbranched rays in the dorsal, pectoral and pelvic fins, the number of predorsal scales, body depth, etc. Bryconamericus galvisi, can be distinguished from other species of Bryconamericus by its single peduncle spot, high branched anal fin ray, the lateral line scales count, and elongated body. This species is similar to B. caucanus and can be distinguished by the number of teeth on the maxilla and by the number of vertebrae. The genus Bryconamericus is a natural and valid group, which is related to Hemibrycon. Moreover the Knodus and Eretmobrycon are synonym of Bryconamericus.     

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.     

A new species of Gobius (Perciformes: Gobiidae) from the Mediterranean Sea and the redescription of Gobius bucchichi

A new species of the gobiid genus Gobius (Gobiidae, Perciformes), Gobius incognitus sp. nov. is described from the Mediterranean Sea, and its most morphologically similar species Gobius bucchichi is redescribed. The new species is distinguished from its congeners by: scales in lateral series 51–59; predorsal scales 25–35; opercle scaled in adults with 10–16 scales present; pectoral fin with ray count 18–20 and free tips on upper rays well developed and on the first ray longer than two thirds of the entire ray length; pelvic disc complete and with well‐developed anterior membrane without lateral lobes; anterior oculoscapular canal with pore α at rear of orbit; oculoscapular row x¹ not extending forwards to pore β; suborbital row d discontinuous with large gap below suborbital rows 3 and 4; eye diameter 1·08–1·32 in snout length; by pigment rows on cheek and pigmentation on pectoral‐fin base.     

棒花鱼形态特征的两性异形和雌性个体生育力

测定了棒花鱼(Abbottina rivularis)繁殖期形态特征包括体长、头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、胸鳍腹鳍间距、尾柄长、尾鳍长和体重的两性异形和雌性个体生育力。结果表明,雄性个体的数量显著多于雌性个体,雄性个体的体长显著大于雌性个体。特定体长的雌性个体的胸鳍腹鳍间距显著大于雄性个体,头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、尾柄长和尾鳍长显著小于雄性个体,雌雄两性体重不存在显著差异。棒花鱼的怀卵数量与体长和体重回归关系显著。偏相关分析显示,当控制第三者恒定时,怀卵数量与体长和体重呈正相关但不显著。棒花鱼存在个体大小和其他局部特征显著的两性异形,雌性个体主要通过腹腔容积的增加提高个体生育力。棒花鱼形态特征的两性异形是性选择和生育力选择共同作用的结果。     

<Emphasis Type="Italic">Careproctus surugaensis</Emphasis> sp. nov. (Liparidae), a new snailfish from Suruga Trough,Japan

A new species of liparid fish Careproctus surugaensis is described from a single specimen collected between 1,450 and 1,570 m depth on the northern part of Suruga Trough, Suruga Bay, Japan. It can be distinguished from all currently recognized congeners by the following combination of characters: 50 total vertebrae, 47 dorsal-fin rays, 39 anal-fin rays, 32 pectoral-fin rays, 10 principal caudal-fin rays, pectoral proximal radials 4 (first to third with notches); trilobate teeth on both jaws, gill slit 7.1 % SL, extending in front of 7th pectoral fin ray base; maximum body depth 19.1 % SL, disk length 7.9 % SL, anus midway between posterior margin of pelvic disk and anal-fin origin; body and fins light orange except blackish peritoneum.     

Hemitriakis complicofasciata, a new whitefin topeshark (Carcharhiniformes: Triakidae) from Japan

Hemitriakis complicofasciata sp. nov. is described from 18 specimens from the waters of the Ryukyu Islands, southern Japan. This new species is distinguishable from other congeners by the following characters: higher vertebral counts (46–52 monospondylous vertebrae and 124–131 precaudal total vertebrae), presence of a developed posterior nasal flap, first dorsal fin origin anterior to free rear tips of pectoral fin, shorter snout length (snout tip to oral length less than 1.8 times internarial width), absence of an accessory cartilage at symphysial part of upper jaw, and dark complicated lines and rings on embryos and juveniles.     

A new pearleye (Teleostei,Aulopiformes) species from the Oligocene of Romania

A new pearleye species of the alepisauroid family Scopelarchidae, Scopelarchoides neamticus sp. nov., is described herein based on two specimens from the Oligocene Lower Dysodilic Shales Formation, cropping out in the Pietricica Mountain, Romanian Eastern Carpathians. The new species described herein exhibits a unique combination of features (including head length about 25% of SL; coracoid remarkably expanded; both preorbital and postorbital lengths larger than orbit diameter; 50 or 51 vertebrae; dorsal fin with nine or ten rays; anal-fin with 28 rays; length of anal fin base about 30% of SL; preanal distance almost 60% of SL; pelvic fin insertion located just under the second dorsal fin ray; pectoral fins only slightly longer than pelvic fins; caudal fin with 19 principal rays plus 14 upper and 13 lower procurrent rays) that justifies its recognition as a new species of the genus Scopelarchoides. Both morphological and meristic features suggest a certain degree of similarity between S. neamticus sp. nov. and the extant species Scopelarchoides signifer. The fossils of the new Oligocene species described herein represent the oldest known skeletal record of Scopelarchidae.     

A new genus and species of prickleback (Perciformes: Stichaeidae) from Japan

A stichaeid fish, Xenolumpenus longipterus gen. et sp. nov., is described on the basis of 2 specimens (107.1–114.9 mm in standard length) collected from 167 to 300 m in the northern Sea of Japan off southern Hokkaido, Japan. Xenolumpenus is unique among all known genera of the subfamily Lumpeninae in having all pectoral, pelvic, and anal fin rays elongate and unbranched with fin membranes well-incised. Xenolumpenus longipterus can be further distinguished from all species of the subfamily in having the following combination of characters: dorsal fin XLVI–XLVIII; anal fin II, 28–29; pectoral fin 11; large black blotches on pectoral fin; and black ocellus on caudal fin.     

Two new species of the genusAmblyeleotris (Pisces: Gobiidae) from the Ryukyu Islands,Japan

Two new shrimp-associated gobies,Amblyeleotris yanoi sp. nov. andA. masuii sp. nov. are described on the basis of specimens from Iriomote-jima Island and Okinawa-jima Islands, Okinawa Prefecture, Japan.A. yanoi is distinguished from other members of the genus by the combination of the following characters: 14 anal fin soft rays, 19 pectoral fin rays, 97–103 longitudinal scales, a candle flame-shaped marking on the caudal fin, a very low membrane connecting the pelvic fins and absence of a ventral frenum.A. masuii differs from all other congeners by having 92–97 longitudinal scales, the length of the interpelvic connecting membrane relative to the longest pelvic fin ray (0.43–0.66), black blotches on the sides of the chin, and blue spots on the opercle and preopercle.     

Callionymus omanensis,a new species of dragonet from Oman,north‐western Indian Ocean (Teleostei: Callionymidae)

A new species of deep‐living dragonet Callionymus omanensis from Oman is described on the basis of a single male specimen collected in a trawl from 500 m depth off the coast of Oman. The new species is characterized within the subgenus Bathycallionymus by having a small branchial opening; head short (3·9 in proportion to standard length); eye large (2·4 in proportion to head length); preopercular spine with a long, upcurved main tip, with a small antrorse barb and a larger antrorse spine, and with a strong antrorse spine laterally at the preopercular‐spine base, ventral margin smooth; first dorsal fin slightly higher than second dorsal fin (male); second dorsal fin distally straight; 17 pectoral fin rays; distal end of caudal fin slightly pointed, with two median unbranched rays bearing short filaments; first dorsal fin with basal black spot reaching from first to fourth membranes, third membrane with an ocellated distal black blotch; second dorsal fin with vertical dark grey bars; distal three‐fourths of anal fin black; upper half of caudal fin with oblique dark grey bars; pelvic fin dark grey, second ray basally with a black blotch. The new species is compared with similar species. Revised keys to callionymid species of the western Indian Ocean and the Red Sea, as well as species of the subgenus Bathycallionymus, are presented.     

Channa panaw, a new channid fish from the Irrawaddy and Sittang River basins, Myanmar

Channa panaw sp. nov. (Channidae) is described from 32 specimens collected from the Irrawaddy and Sittang River basins, Myanmar. It is distinguishable from all known congeners by the combination of the following characters: 32–35 dorsal fin rays, 23–24 anal fin rays, 17–20 pectoral fin rays, 39–41 lateral line scales, 39–41 total vertebrae, one large scale on each side of the lower jaw (rarely 2 on one side), pelvic fin length always more than 50% of pectoral fin length, and 7–12 irregular black blotches on the upper half of the body.