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1.
A new cave‐dwelling fish species Triplophysa guizhouensis is described based on specimens collected from Guizhou, China, in a subterranean system interconnected with the Hongshui River drainage. The species can be distinguished from its congeners by a combination of characters: eyes present; caudal fin with 14 branched rays; inner gill rakers of first gill arch 8–10; posterior chamber of air bladder developed; and body posterior of dorsal fin scaled. A key to species of Triplophysa in the Pearl River basin is provided.  相似文献   

2.
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.  相似文献   

3.
A rare Australian bothid flounder.Asterorhombus bleekeri (Macleay), is redescribed from the holotype and ten additional specimens from the east coast of Qeensland, Gulf of Carpentaria and Rowly Shoal (Western Australia). The species is transferred fromArnoglossus Bleeker toAsterorhombus Tanaka because of the lack of obvious sexual dimorphism in the interorbital width and pectoral fin length, the lack of rostral and orbital spines, the yellow-white blind side body coloration, and the deeply cleft parhypural and hypural plates. The definition ofAsterorhombus was emended as follows: the first dorsal fin ray continuous with or separated from remaining fin rays and gill rakers slender or stubby, with or without serrations.Asterorhombus osculus sp. nov., formerly briefly described in the literature as unidentified species ofEngyprosopon, was described from eight specimens from the northwestern coast of Australia. The new species is most similar toA. bleekeri in lacking sexual dimorphism, and having the caudal skeleton with deep clefts, two or three rows of teeth on the upper jaw and a pair of conspicuous black spots on the caudal fin, in addition to a similar general appearance, but is distinguished from the latter by shorter gill rakers, a very small mouth and feebly ctenoid scales on the ocular side. Both species clearly differed fromA. intermedius andA. fijiensis in having two (or three) rows of teeth on the upper jaws, slender gill rakers without serrations, first dorsal fin ray continuous with the other fin rays, and a pair of conspicuous black spots on the caudal fin.  相似文献   

4.
Combined results based on morphological characters and analyses of partial sequences of the 16s rRNA and coI genes confirm the validity of a new, cryptic, symphurine tonguefish from the western North Pacific Ocean. Symphurus leucochilus n. sp., a diminutive species reaching sizes to c. 67 mm standard length, is described from nine specimens that were collected from fish‐landing ports and from trawls made at c. 150 m off Taiwan and Japan. Symphurus leucochilus shares many similar features with those of Symphurus microrhynchus and that of several undescribed species that are morphologically similar to S. microrhynchus. Symphurus leucochilus has also been misidentified as Symphurus orientalis in fish collections because of shared similarities in some aspects of their morphology. The new species differs from all congeners by the following combination of meristic, morphological and pigmentation features: a predominant 1–2–2–2–2 pattern of interdigitation of proximal dorsal‐fin pterygiophores and neural spines; 12 caudal‐fin rays; 89–92 dorsal‐fin rays; 76–80 anal‐fin rays; 49–51 total vertebrae; four hypurals; 75–83 longitudinal scale rows; 32–35 transverse scales; 15–17 scale rows on the head posterior to the lower orbit; absence of a fleshy ridge on the ocular‐side lower jaw and a membranous connection between the anterior nostril and lower part of the eye; a narrow interorbital space and dorsal‐fin origin anterior to the vertical through the anterior margin of the upper eye; absence of both dermal spots at bases of anterior dorsal‐fin rays and melanophores on the isthmus; uniformly yellow to light‐brown ocular‐side colouration without bands; dorsal and anal fins with alternating series of dark rectangular blotches and unpigmented areas; a uniform white blind side and a bluish‐black peritoneum. Despite overall similarities in morphology between S. leucochilus and S. orientalis, as well as between two of the nominal species morphologically similar to S. microrhynchus, analyses of partial 16s rRNA and coI gene sequences show that S. leucochilus, S. orientalis and the two other nominal species represent three distinct lineages within the genus Symphurus.  相似文献   

5.
Polydactylus bifurcus sp. nov. is described on the basis of a single specimen collected from Lombok Island, Indonesia. The new species is distinguished from all other Indo-Pacific Polydactylus species by the following combination of characters: 15 pectoral fin rays, 5 pectoral filaments, 69 pored lateral line scales, 30 gill rakers, second spine of first dorsal fin very strong and lateral line bifurcated on caudal fin base, extending to posterior margins of upper and lower caudal fin lobes. Received: October 19, 2000 / Revised: April 21, 2001 / Accepted: April 25, 2001  相似文献   

6.
7.
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.  相似文献   

8.
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.  相似文献   

9.
Astyanax anai, a new species of characid fish, is described from the Sixaola River basin, eastern Costa Rica–western Panama, Central America. The new species can be distinguished from all other congeners by the following combination of characters: premaxillary teeth 4–5 at the inner series and 4–6 at the outer series; maxillary teeth tricuspid, 2–4; predorsal scale series irregular and incomplete, with an unscaled space behind tip of supraoccipital process and 12–14 scales; lateral line scales 34–39; humeral region with a conspicuous black and rounded to horizontally ovate spot and two diffuse brown and vertically elongate bars (the first through the rounded to horizontally ovate spot, the second 2–4 scales behind the first); body depth 36·6–42·3% of standard length (LS); midlateral stripe formed by a series of 10–14 anteriorly‐directed dermal herringbone, or chevron‐shaped, marks, most apparent in juveniles and in preserved specimens, extending above the lateral line from the black humeral spot or just behind it (from the second vertical bar) to the caudal peduncle; scale rows from lateral line to base of first dorsal‐fin ray 8–9; scale rows from lateral line to base of pelvic fin 7–8; pre‐anal distance 53·9–61·9% of LS; total anal‐fin elements 29–33; caudal spot elongated, rhomboid or rectangular, with its anterior margin surpassing the middle of the caudal peduncle, usually reaching the anal‐fin insertion, posteriorly covering 4–7 principal caudal‐fin rays and not extending onto the ventral and dorsal margins of the caudal peduncle, covering 3–5 horizontal scale rows. In order to test the phylogenetic relationships of the new taxon in relation to the other North and Central American species of the genus, a new phylogenetic hypothesis based on a reanalysis of the morphological matrix by Schmitter‐Soto (2016) is proposed. A key to the lower Central American (southern Nicaragua to eastern Panama) species of Astyanax is also provided.  相似文献   

10.
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.  相似文献   

11.
中国南海蛇鳗科一新纪录属及一新纪录种(鱼纲,鳗鲡目)   总被引:1,自引:0,他引:1  
报道了中国南海蛇鳗科1新纪录属Echelus Rafinesque,1810和1新纪录种Echelus uropterus(Temminck et Schlegel,1846).该属的特征为:尾鳍、胸鳍存在;背鳍起点在胸鳍后端之前;头部无额骨孔、眶后孔和上颞骨孔;鳃孔中等大;鳃膜骨条连于舌骨或上舌骨尖前.该种的特征:尾尖柔软;颌齿和犁骨齿颗粒状,带形;后鼻孔在上唇边缘外侧.  相似文献   

12.
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.  相似文献   

13.
高原特有条鳅鱼类两新种在广西的发现及其动物地理学意义   总被引:16,自引:4,他引:12  
描述了采自广西都安县红水河水系的条鳅亚科鱼类2个新种:丽纹云南鳅yhnnanilus pulcherrimussp.nov.在侧线长度、鳞片分布、鳍条数目、尾型、吻须长度等方面与侧纹云南鳅yunnanilus pleurotaenia(Regan,1904)最为相似,但新种独特的斑纹和上下唇的长乳突可明显与之区别,二者在一些度量特征上也有区别。黄体高原鳅Triplophysa flavicorpus sp.nov.与同分布于西江水系的南丹高原鳅T.nandanensis Lan et al.较为相似,并以下列特征组合与高原鳅属所有已知种相区别:背鳍分枝鳍条10根、臀鳍分枝鳍条6~7根、体被细鳞、侧线完全、具6条宽横斑和1条沿侧线的细纵纹、尾鳍深分又、尾鳍基具1半圆形黑斑、尾鳍上下叶各具2条黑色横斑、腹鳍末端后伸超过肛门、腋部具发达的肉质鳍瓣、上唇中央完全中断等。云南鳅属和高原鳅属均是高原特有类群,前者仅分布于云南东中部地区,后者则集中分布于青藏高原。两个新种的分布地均远离这两个属的分布中心,而且呈间断分布。通过各自相近种谱系关系分析,推测这种特殊的分布格局是通过隔域分化形成的。  相似文献   

14.
Caucasichthys kumaensis gen. et sp. nov., a representative of a new monotypic perciform family Caucasichthyidae, from the Middle Eocene (Bartonian, Kuma Horizon) of the North Caucasus (Gorny Luch locality) is described. The new family is characterized by elongated body, strong preopercular spine in adults, absence of supraneurals, large pelvic fins, long caudal peduncle, and anal fin longer at the base than soft dorsal fin. Scales vary from cycloid to spinoid on different parts of the body. Caucasichthys shares a number of apomorphic features with members of certain percoid families, most notably the Priacanthidae. However, because of its unique combination of features, the new family cannot be properly placed within any existing perciform suborder and it is placed incertae sedis among the Perciformes.  相似文献   

15.
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   

16.
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   

17.
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  相似文献   

18.
Ray‐finned fishes actively control the shape and orientation of their fins to either generate or resist hydrodynamic forces. Because of the emergent mechanical properties of their segmented, bilaminar fin rays (lepidotrichia), and actuation by multiple muscles, fish can control the rigidity and curvature of individual rays independently, thereby varying the resultant forces across the fin surfaces. Expecting that differences in fin‐ray morphology should reflect variation in their mechanical properties, we measured several musculoskeletal features of individual spines and rays of the dorsal and anal fins of bluegill sunfish, Lepomis macrochirus, and assessed their mobility and flexibility. We separated the fin‐rays into four groups based on the fin (dorsal or anal) or fin‐ray type (spine or ray) and measured the length of the spines/rays and the mass of the three median fin‐ray muscles: the inclinators, erectors and depressors. Within the two ray groups, we measured the portion of the rays that were segmented vs. unsegmented and branched vs. unbranched. For the majority of variables tested, we found that variations between fin‐rays within each group were significantly related to position within the fin and these patterns were conserved between the dorsal and anal rays. Based on positional variations in fin‐ray and muscle parameters, we suggest that anterior and posterior regions of each fin perform different functions when interacting with the surrounding fluid. Specifically, we suggest that the stiffer anterior rays of the soft dorsal and anal fins maintain stability and keep the flow across the fins steady. The posterior rays, which are more flexible with a greater range of motion, fine‐tune their stiffness and orientation, directing the resultant flow to generate lateral and some thrust forces, thus acting as an accessory caudal fin. J. Morphol., 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

19.
20.
A new genus and species of the subfamily Bythitinae (Bythitidae),Hastatobythites arafurensis, is described on the basis of two specimens from the Arafura Sea. The genus is unique in the subfamily in having two anteriorlydirected spines, one on the frontal and one on the mesethmoid. It is also distinguishable from all other genera in the subfamily by the following combination of characters: head scales absent; squamation on body incomplete; maxillary expanded posteriorly; no thin pore-bearing skin flap over opercle; opercle thin, weak, without distinct spine; jaw teeth conical; vomerine and palatine teeth present; developed gill rakers on 1 st arch 3; pelvic fins with 1 ray in each; pectoral peduncle elongated, with 16 rays; caudal fin rays 12; branchiostegal, rays 8; precaudal vertebrae 15, with tips of 6th to 12th neural spines truncated.  相似文献   

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