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1.
Amblyceps crassioris, a new species of amblycipitid catfish, is described from the Mahanadi River basin in Odisha, India. The new species can be distinguished from its congeners in having a combination of the following characters: a deeply forked caudal fin, centrally projecting hooks on proximal lepidotrichia of median caudal-fin rays absent, jaws equal in length, lateral line absent, body depth at anus 15.1%–19.5% standard length (SL), caudal peduncle depth 13.0%–18.3% SL, adipose-fin base length 21.1%–27.1% SL, eye diameter 7.35%–14.1% head length and 38 total vertebrae.  相似文献   

2.
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.  相似文献   

3.
A new species of glyptosternine catfish, Oreoglanis infulatus , is described from the Lam River drainage in central Vietnam. The new species is distinguished from all its congeners by possessing the following combination of characters: a dark band running across the anal fin, a lunate and uniformly dark caudal fin, the lower lip lacking a medial notch and with a lobulate posterior margin, maxillary barbel with a rounded tip, length of caudal peduncle 19·0–22·6 % L S, depth of caudal peduncle 2·6–3·2 % L S, post-adipose distance 6·8–8·0 % L S, eye diameter 10·5–12·1 % L H, 12 principal caudal-fin rays.  相似文献   

4.
Based on our reexamination of the 9 specimens including the neotype, Bregmaceros lanceolatus is recharacterized and diagnosed by the following combination of features: caudal fin rounded; scales present on gill cover; dorsal surface of snout unpigmented or with a few chromatophores; isthmus pigmented with punctate chromatophores; two parapophyses on abdominal vertebrae; dorsal rays (D) 65–74; anal rays (A) 67–74; vertebrae (V) 58–61; longitudinal scales (LS) ca. 82–88; principal caudal rays (PC) 16–18; head length (HL)/standard length (SL) 14.0–15.5%; caudal peduncle depth/SL 3.2–4.2%. Based on 27 specimens, B. pseudolanceolatus sp. nov. is described. This species is closely similar to B. lanceolatus, but is diagnosed by the following combination of features: caudal fin rounded; scales present on gill cover; dense concentration of chromatophores on dorsal surface of snout; isthmus colorless; one board-like parapophysis on the last three abdominal vertebrae; D 58–64; A 58–67; V 52–55; LS ca. 68–77; PC 14–16; HL 15.5–18.4% SL; caudal peduncle depth 4.1–5.2% SL. Bregmaceros pseudolanceolatus is known from around the Taiwan Strait, southern East China Sea, South China Sea, Gulf of Thailand, Timor Sea, Arafura Sea, and eastern Bay of Bengal.  相似文献   

5.
A new species, Olyra parviocula, is described from the Kameng River, Brahmaputra River drainage in Arunachal Pradesh, northeastern India. The new species differs from congeners in having small eye diameter 5–8% HL; short adipose fin, not confluent with caudal-fin, its base length 9–12% SL; dorsal-fin branched rays 6; anal-fin rays viii–xi, 8–10 and maxillary barbel almost reaching pelvic-fin base. A key to identification of all valid species of Olyra is provided.  相似文献   

6.
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 (LS), 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% LS, caudal peduncle depth 4·1–4·2 times its length.  相似文献   

7.
The taxonomy of French ninespined sticklebacks (Pungitius spp.) has long been controversial. To clarify the taxonomy in this group, we use mitochondrial (COI) and nuclear (RNF213) sequence markers, as well as morphological data. In France, both genetic markers discriminate three evolutionary lineages. Morphological analysis on fresh and type specimens supports the different lineages and the existence of three species in France. Pungitius pungitius, occurring in the North of France and Rhone basin, is characterized by specimens longer than 35 mm SL, by a flat head with a straight or slightly concave snout, typically 9–10 dorsal spines, 10–11 dorsal soft rays, 9–10 anal soft rays, 0–12 scutes on the caudal peduncle with a keel reaching the last anal‐fin ray, longer pelvic fin, post‐dorsal and caudal peduncle lengths, and a slim caudal peduncle (caudal peduncle depth/length 11.8%–21.9%). Pungitius laevis, occurring in France, in the English Channel basins and Loire drainage, differs from the other species by a head rounded with concave snout in specimens longer than 35 mm SL, accentuating the impression of fleshy lips, 0–4 scutes on the caudal peduncle and a higher caudal peduncle depth/length ratio (15.7%–34.5%). Finally, Pungitius vulgaris, endemic to the Vienne River and rivers of south‐western France as far north as the Garonne estuary, is differentiated by a rounded head with a straight or slightly convex snout, the absence of scutes on the caudal peduncle and by having 11 pectoral‐fin rays. Our data confirm the existence of a hybridization zone in the North of France between P. pungitius and P. laevis. As a result, Pungitius lotharingus is invalid, as it was described based on hybrid specimens. A lectotype for P. laevis was designated because the syntypes included hybrids. This revision provides new perspectives for evolutionary biology studies and will have consequences for Pungitius conservation in France.  相似文献   

8.
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.  相似文献   

9.
王丹  赵亚辉  张春光 《动物学报》2005,51(3):423-430
长期以来,国内绝大多数有关研究者将海鲇属Arius中腭骨齿单侧3群的个体鉴定为海鲇A.thalassinus。基于中国科学院动物研究所标本馆馆藏海鲇标本的研究发现,标本中存在两种腭骨齿的分化类型;经文献查证,其中一种应为双线海鲇A.bilineatus,该种在我国尚未见有研究报道,为一新记录种。双线海鲇与海鲇外形相似,但前者吻较钝,唇薄,腭骨齿于前部相连,游离脊椎骨数目较多(46—51 vs 38—43),臀鳍鳍条数较多(15—18 vs 1316),无囟门沟,从而可与后者相区别[动物学报51(3):423—430,2005]。  相似文献   

10.
During a re-examination of museum specimens of Triplophysa species, some specimens that had been collected from the Jialonghe River in Yunnan Province, China, in April 1975, were identified as a new species. Triplophysa parvus n. sp. can be distinguished by the following combination of characters: dorsal fin rays 3, ; anal fin rays 3, ; pectoral fin rays 1, 11; scales absent; two saddle-like blotches with fuzzy borders cranial to the dorsal fin and four saddle-like blotches caudal to the dorsal fin; distal margin of the dorsal fin emarginate; pelvic fin reaching caudally almost to the anus; anus located immediately cranial to the origin of the anal fin; caudal fin forked; caudal chamber of air bladder reduced to a small free protuberance; head slightly laterally compressed, head deeper than wide at nape; length of caudal peduncle being 18.0–20.0% of standard length; depth of caudal peduncle being 7.8–8.4% of standard length; eye diameter 17.6–21.4% of head length; body depth being 60.7–70.2% of head length; caudal peduncle depth being 39.1–45.0% of caudal peduncle length; and body width at the base of caudal peduncle 59.0–68.0% of the body depth at the base of caudal peduncle. These characters allow a distinction from the similar species of T. nasobarbatula, T. nandanensis, and T. macromaculata.  相似文献   

11.
A new loach species, named Triplophysa jianchuanensis, has been recognized in collections from Jianchuan in Dali Prefecture, Yunnan, China. Triplophysa jianchuanensis can be distinguished from the other Triplophysa species by the following combination of characteristics: smooth skin, scaleless; lateral line complete; head long (26.7–29.8% of SL); eyes large (25.9–31.0% of dorsal head length); snout shorter than postorbital length (26.9–30.1% of HL); middle of lower lip interrupted and forming a pair of furrows; lower jaw spoon-like with obtuse edge; posterior chamber of air bladder completely degenerated; intestines short, bending in zigzag-shape behind stomach; pelvic-fin tip not reaching anus; caudal fin emarginate; branched rays of dorsal fin 7; branched rays of caudal fin 16. A key to the known species of Triplophysa from the Lancangjiang River is provided.  相似文献   

12.
中国广西金线鲃属一新种(鲤形目,鲤科,鲃亚科)   总被引:2,自引:1,他引:1  
2001年5月作者于广西环江县驯乐乡顺宁村采集到金线鲃属盲鱼5尾,经鉴定为一新种.新种眼睛完全退化,头后急剧隆起但尚未形成额骨突等体型特征与无眼金线鲃Sinocyclocheilus anophthalmus Chen et Chu,1988相似,而明显有别于属内其他物种.但两者在以下性状上又存在明显区别:1)新种背鳍硬刺纤弱;而无眼金线鲃的背鳍硬刺比较粗壮;2)新种背部自额骨后隆起,但是额骨顶部并不隆起;无眼金线鲃则自眼眶上方的额骨顶部开始显著隆起,直至肩部;3)新种侧线平直;无眼金线鲃的侧线在腹鳍和臀鳍之间的上方有一比较明显的向上弯曲;4)新种胸鳍长,超过腹鳍起点;无眼金线鲃胸鳍不超过腹鳍起点;5)分布区亦有所不同,新种分布于柳江水系;无眼金线鲃则分布于南盘江水系.此外,在一些可测性状上二者亦有区别,在标准长与体高和头长的比例、尾柄长与尾柄高的比例、侧线鳞的数目等性状上都有所差异.  相似文献   

13.
A new species of soldierfish, Ostichthys spiniger, from off northern New Ireland, Papua New Guinea, is described on the basis of a single specimen collected with a trawl at 180-181 m depth near Kavieng. The new species is characterised by the following characters: scales above lateral line to mid-base of spinous portion of dorsal fin 31/2; no half-scale present anterior to first lateral-line scale; dorsal profile of head nearly uniformly convex; anterior end of each nasal bone with a sharp, forwardly directed spine; a strong spine at the corner of preopercle, which is significantly larger than other serrations; pectoral-fin rays 17; lateral-line scales 29; gill rakers 8 + 13; last dorsal-fin spine shorter than penultimate spine; body depth 2.2 in SL; HL 2.4 in SL; snout very short, 6.6 in HL; least depth of caudal peduncle 4.9 in HL. The new species is compared with other species in the genus. A revised key to the species of Ostichthys is presented. The new species is most similar to O. acanthorhinus.  相似文献   

14.
A new epigonid fish, Epigonus cavaticus, is described on the basis of eight specimens (59.2–69.5 in standard length: SL) collected from a cave at depth 20 m, southern fringing reef of Ngemelis Island, Palau. The species differs from other congeners by having minute teeth on both jaws, no opercular spine, pyloric caeca 7–8, gill rakers 25–27, total pored lateral line scales 48–50, dorsal fin rays VII-I, 10–11 (mode VII-I, 10), pectoral fin rays 16, vertebrae 10 + 15, body depth 21.4–25.0% SL, pectoral fin length 22.7–24.6% SL, eye diameter 44.4–47.5% head length: HL, upper jaw length 40.2–42.5% HL. Four paratypes (63.7–66.8 mm SL) of the new species are female with mature gonads, it is the smallest in size at sexual maturity among the congeners.  相似文献   

15.
广西洞穴鱼类一新种(鲤形目:鳅科)   总被引:2,自引:0,他引:2  
本文记述了采自广西河池地区的洞穴鱼类一新种,并讨论了其分类地位。透明间条鳅,新种Heminoemacheilus hyalimus sp.nov.与同属种的区别主要表现在尾鳍分枝鳍条数目较少、须较短、眼睛完全退化、头较大和尾柄较细长等方面。  相似文献   

16.
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.  相似文献   

17.
Parakysis notialis sp. nov. is described from the Barito River drainage in southern Borneo. It can be distinguished from congeners in having a unique combination of the following characters: head length 26.5–27.0% SL, conical head, presence of median concavity on margin of lower lip, presence of laterosensory canal pore between inner and outer mandibular barbels, branched outer mandibular barbels, branches of inner mandibular barbels separated, deeply forked caudal fin with pointed lobes, 5 pectoral fin rays, 10 branched principal caudal fin rays, sparsely pigmented caudal fin, and absence of light brown saddle from base of posteriormost dorsal fin ray to caudal peduncle. Received: February 11, 2002 / Revised: September 4, 2002 / Accepted: October 11, 2002 Acknowledgments We thank Takashige Idei for the gift of the specimens of the new species, and Darrell Siebert (BMNH), David Catania (CAS), Karsten Hartel (MCZ), Douglas Nelson (UMMZ), and Kelvin Lim (ZRC) for permission to examine material under their care. Funding from a Block Grant from the Department of Ecology and Evolutionary Biology, University of Michigan and the Rackham School of Graduate Studies, University of Michigan provided financial support for this project. Correspondence to:Heok Hee Ng  相似文献   

18.
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.  相似文献   

19.
Morphological variations in bluegill, Lepomis macrochirus, including growth-related changes, sexual dimorphism and morphological differences between populations in different habitats, were examined in samples from three reservoirs in Kagawa, Japan. Body measurements demonstrated frequent growth-related proportional changes, particularly in body depth, body width, caudal peduncle length and head length, which all showed relative increases, whereas first dorsal fin length, caudal fin length and orbital diameter became relatively shorter. Body weight increased relatively with growth, with relative growth coefficients of 3.339–3.454 for regressions between total length and body weight. Such body weight increases were likely due to the relative increases in body depth and width, and caudal peduncle depth. Although counts of fin spines, fin rays and gill rakers did not change with growth, those of scales tended to increase. Males were significantly larger than females in body depth, caudal peduncle length, head length and body weight. Sexual dimorphism was also apparent in body coloration during the breeding season. In addition, a number of morphological differences were observed between individuals from different habitats.  相似文献   

20.
A new species of the genus Glyptothorax, Glyptothorax obliquimaculatus sp. nov. is described from the Xiaohei River, a tributary of the Nanting River, Salween drainage, in southwestern Yunnan province, China. This new species can be distinguished from its congeners by the following combination of characteristics: unculiferous ridges of the thoracic adhesive apparatus extending anteriorly onto the gular region; body with irregular dark blotches scattered along lateral surface (blotches mostly oblique); skin smooth on head and body; dorsal spine smooth without serrations on its posterior margin; lips smooth; posterior margin of pectoral spine with 7–8 serrations; dorsal-fin base 11.0–13.2% SL; pectoral-fin length 15.6–19.6% SL; depth of caudal peduncle 8.6–9.8% SL; head width 19.1–24.0% SL; nasal barbel length 23.3–33.3% HL.  相似文献   

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