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1.
Aequidens plagiozonatus sp.n. is described from 49 specimens collected in the northern Paraguay river system. It is the only known species of Aequidens Eigenmann & Bray in the La Plata basin. Distinguishing characteristics include the slanting vertical bars on the sides, discontinuous horizontal lateral band, immaculate or very sparsely dotted caudal fin and short pectoral fin.  相似文献   

2.
中国广西金线鲃属一新种(鲤形目,鲤科,鲃亚科)   总被引:1,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   

3.
金线鲃属三新种记述   总被引:6,自引:0,他引:6  
笔者于19661988年在云南东部的南盘江水系采到一批金线鲃标本,其中有3个系科学上尚未记载的新种,现描述于后。    相似文献   

4.
本文为四川省条鳅亚科鱼类分类研究的第一部分,对分布于四川省的副鳅属(Paracobitis)、条鳅属(Nemacheilus)和山鳅属(Oreias)鱼类进行了比较系统的整理,这3个属分布在四川共有5种和亚种,其中乌江副鳅(Paracobitis wujiangensis sp.nov.)为新种。  相似文献   

5.
We investigated the size at maturation, breeding season, and morphological development of larvae and juveniles of a freshwater pipefish Microphis leiaspis, which belongs to Gastrophori, collected from three rivers on the northern part of Okinawa-jima Island, Japan. The minimum size of brooding males was 105–123 mm in standard length (SL). The smallest mature female was estimated to be ca. 130 mm SL from the analysis of gonadosomatic index (GSI) and histological observations of gonads. The breeding season was estimated to be from June to December according to monthly changes in female GSI, histological observations of gonads, and monthly changes in the occurrence of brooding males. The number of eggs in the male brood pouch ranged from 75 to 241 (mean ± SD: 152 ± 52, n = 22). The male releases newly hatched larvae in freshwater areas. After newborns grow in the sea, they return to freshwater areas of the rivers and attain maturity. Microphis leiaspis was conformed to have an amphidromous life history. Notochord length of the released larvae was 6.1 mm, with a well-developed finfold. Larvae attained 11.1 mm SL, formation of the caudal and dorsal fin rays was complete, and the caudal fin became lozenge shaped at 30 days after the release, and juveniles reached 36.0 mm SL at 63 days after release. In the period between 30 and 63 days after the release, formation of all fins except the pectoral fins was completed, and caudal fin rays were extended and sector shaped with deep slits between each fin ray. The morphology of the released larvae of M. leiaspis is similar to that of Gastrophori species, and the morphology of juveniles similar to other species of Microphis.  相似文献   

6.
澜沧江短吻鱼属鱼类   总被引:2,自引:0,他引:2  
短吻鱼属Sikukia隶属于鲤科亚科(Cyprinidae:Barbinae),wv dm  相似文献   

7.
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   

8.
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   

9.
A new cobitidid, Cobitis elazigensis, is described from Anatolian Turkey in the province of Elazi?. The new species differs from all other members of the genus by having the following combination of characters: two Canestrini’s scales on the pectoral fin, a suborbital spine with a dorso-lateral branch (rarely simple and unbranched), large size, over 180 mm total length, total vertebrae 47–49, lateral spots reduced or absent, a spot at the upper caudal fin base, scales longer than wide with a small focus, dorsal fin rays III, 5–6, usually 6, ventral fin rays III, 6–7, usually 6, and pectoral fin rays I, 7–9.  相似文献   

10.
Teleocichla preta nov. sp. inhabits the rapids along the Rio Xingu and lower portion of the Rio Iriri. It is the largest species in the genus, reaching 121·3 mm standard length (LS) while others do not reach more than 87·8 mm LS. Teleocichla preta is distinguished from all other species of Teleocichla by the unique blackish (in live specimens) or dark brown (preserved specimens) overall colouration of the body, which masks the faint vertical bars or zig‐zag pattern of blotches on the flanks. Teleocichla preta also has a deeper body and a deep laterally compressed caudal peduncle, unlike any other congener, as well as a stout lower pharyngeal tooth plate bearing molariform teeth on its median area.  相似文献   

11.
成年大鼠纹状体、边缘区和苍白球的计算机三维结构重建   总被引:2,自引:0,他引:2  
应用计算机图形技术在大鼠脑的连续冠状切片Nissl染色的基础上通过Onyx2超级图形工作站对大鼠脑的纹状体进行了三维重建。结果提示:大鼠纹状体由尾壳核、苍白球和边缘区三部分组成,其中边缘区位于尾壳核和苍白球之间,被二完全包绕;尾壳核呈近似的内凹半球形,嘴尾径最大的为6.2mm;背腹径最大为4.9mm;宽度(冠状平面上的内外径)为3.5mm。从嘴侧到尾侧随着脑平面的增宽,尾壳核逐渐向外侧(即靠近外轮廓的方向)移位。苍白球呈块形,嘴尾径最大为4.4mm,背腹径最大为2.6mm,宽度(冠状平面上的内外径)最大为1.5mm。位于尾壳核的内侧,除内侧外基它三个方向均被尾壳核包绕。边缘区呈现一个片状扇形结构,嘴侧背腹径大,最大为2.2mm,宽约0.17mm;尾侧背腹径小,为0.8mm,宽约0.13mm。同属壳核和苍白球一样,从嘴侧到尾侧随着脑平面的增宽边缘区亦逐渐向外侧(即靠近外轮廓的方向)移位,其移位的幅度亦明显大于脑平面增宽的幅度;整个边缘区从嘴侧到尾侧呈均匀变化,其片状逐渐变宽,长度(背腹径)逐渐变小,从而形成一个盘状结构。  相似文献   

12.
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   

13.
Light trap collections on oil and gas platforms in the northern Gulf of Mexico off Louisiana from 1995 to 1997 contained young of tessellated blenny Hypsoblennius invemar , freckled blenny Hypsoblennius ionthas , featherduster blenny Hypleurochilus multifilis , molly miller Scartella cristata and seaweed blenny Parablennius marmoreus , which are described. Interspecific differences were: number of dorsal, anal, pelvic and caudal fin elements; number of mandibular pores; presence or absence of canine teeth, hypural 5 and pectoral fin pigment; width of gill openings; length of preopercular spines (in larvae). Size at settlement differed among some taxa, but all five species settled within a narrow size window of c . 1·5 mm standard length ( L S). Hypsoblennius invemar , H. ionthas , H. multifilis and S. cristata settled at mean sizes between 11·3 and 12·1 mm L S, whereas P. marmoreus settled at a mean size of 19·3 mm L S. Sexually dimorphic differences were consistently evident by 17–18 mm L S in all species but P. marmoreus . The two smallest blennies with external characters normally associated with sexual maturity were a 20 mm male and 21 mm female H. multifilis . Primary caudal fin rays began to bifurcate between 17·0 and 18·3 mm L S in H. invemar , H. ionthas , H. multifilis and S. cristata . Hypleurochilus multifilis displayed the external characteristics of being sexually mature at 20–21 mm L S. Thus, bifurcation of primary caudal fin rays was an indicator of approaching sexual maturity in H. multifilis and this may also be true in the other species studied.  相似文献   

14.
The present study was undertaken to establish the normal, healthy features of morphological structures at various developmental stages as achieved under well-defined environmental culture conditions (temperature between 16 and 21°C, salinity 36 ppt, pH around 7.6, and oxygen saturation over 95%) common in aquaculture of the species. The pectoral fin supports began to develop at 2.90 mm total length (TL), followed by those of dorsal fins at 5.5 mm TL, caudal fins at 5.6 mm TL, pelvic fins at 5.9 mm TL and anal fins at 6.0 mm TL. The pelvic fins appeared fully at 7.4 mm TL. Development of dorsal lepidotrichia was first observed at 6.9 mm TL, attaining their final number at 7.6 mm TL. The dorsal spines first appeared at 6.5 mm TL and were complete at 7.4 mm TL. The anal lepidotrichia appeared during the development phase from 6.8 to 8.6 mm TL. At 5.6 mm TL, the upward flexion of the urostyle was initiated. The caudal lepidotrichia formed within the primordial fin at 5.6 mm TL and reached the final count at 7.4 mm TL. The caudal dermatotrichia first appeared at 7.3 mm TL and all forms were observed by 15.5 mm TL. The development pattern of fin supports found in Pagrus pagrus is quite similar to that described for other Sparid species.  相似文献   

15.
A new nematode species, Philometra poblana n. sp., is described based on specimens recovered from skin at the base of the pectoral fins of the cichlid Cichlasoma istlanum (Jordan and Snyder, 1899) from the water spring El Borbollon, in the State of Puebla, Mexico. The new species most closely resembles Philometra gymnosardae and Philometra ophisterni; however, P. poblana can be easily differentiated from the other species by the length of gravid females (7.10-10.43 vs. 14.8-27.0 and 28.67-39.30 mm, respectively), length of caudal projections (0.015-0.023 vs. 0.047 and 0.006-0.009 mm high, respectively), site of infection (skin at base of pectoral fins vs. abdominal cavity, both species), and the host species (Cichlidae vs. Synbranchidae and Scombridae).  相似文献   

16.
The paper investigates the length‐weight relationship of three cichlids species for the southwestern Amazon, Acre state. The individuals were collected at five sites during one year among august/2016 and june/2017 in Quinoá stream (10°06′03.33″S/67°40′11.50″W). The individuals were collected using: seine net, 6 m length, 2.25 high, and mesh size 5 mm, two dip nets, 5 mm mesh, 30 cm width, and 50 cm in length and two sieve with 5 mm mesh, 50 cm width, and 80 cm in length. The results show that one species presented positive allometric growth (Aequidens tetramerus) and the others negative allometric growth (Apistogramma acrensis and Crenicichla semicincta).  相似文献   

17.
在整理华缨鱼属标本时发现,1993年9月在广西壮族自治区天峨县红水河水系地下河采集到的一批标本为一个未经发表的新种,新种订名为大眼华缨鱼(Sinocrossocheilus megalophthalmus)。其下咽齿2行,可与下咽齿3行的7种华缨鱼相区别,而与属内同样具2行下咽齿的贵州华缨鱼(S.guizhouensis)、小口华缨鱼(S.microstomatus)和宽唇华缨鱼(S.labiatus)亲缘关系较近。但:(1)新种胸鳍中点上方无黑斑,背鳍分枝鳍条7,腹鳍分枝鳍条7,背鳍前鳞15—16,眼大,头长为眼径2·5—3·1倍,眼径为头宽44·7%—57·8%,吻须后伸至前后鼻孔之间或眼前缘,口角须后伸至眼前缘至眼中之间或眼中至眼后缘之间,体长为尾柄高8·9—10·7倍,头长为吻长2·5—3·7倍,可与贵州华缨鱼(胸鳍中点上方有一明显黑斑,背鳍分枝鳍条8,腹鳍分枝鳍条8,背鳍前鳞12—14,头长为眼径4·0—5·0倍,眼径为头宽16·6%—20·7%,吻须后伸不达后鼻孔后缘,口角须后伸至眼前缘,体长为尾柄高7·2—8·2倍,头长为吻长1·9—2·2倍)相区别;(2)新种背鳍前鳞15—16,侧线鳞39—40,侧线上鳞4·5—5·5,背鳍分枝鳍条7,鳃耙13,腹鳍末端伸达肛门,眼径为头宽44·7%—57·8%,可与宽唇华缨鱼(背鳍前鳞22,侧线鳞42—45,侧线上鳞6·5,背鳍分枝鳍条8,鳃耙10,腹鳍末端不达肛门,眼径为头宽23·3%—30·0%)相区别;(3)新种与同水系的小口华缨鱼在鳍条数、侧线鳞、体色、斑纹等方面最为相似,但新种围尾柄鳞14/16,眼大,头长为眼径2·5—3·1倍,腹鳍末端伸达肛门,口角须后伸至眼前缘至眼中之间或眼中至眼后缘之间,吻皮边缘深裂成小穗,背鳍起点距吻端较距尾鳍基为近,背鳍长大于头长,体长为尾柄长4·8—5·9倍,头长为吻长2·5—3·7倍,尾柄长为尾柄高1·6—2·1倍,可与之(围尾柄鳞12,眼小,头为眼径4·4—4·6倍,腹鳍末端不达肛门,口角须伸达眼下方,吻皮边缘不开裂或开裂不明显,背鳍起点距吻端等于距尾鳍基,背鳍条约等于头长,体长为尾柄长6·1—6·4倍,头长为吻长2·1—2·4倍,尾柄长为尾柄高1·4—1·5倍)相区别。  相似文献   

18.
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   

19.
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   

20.
贵州高原鳅属鱼类二新种(鲤形目:鳅科:条鳅亚科)   总被引:17,自引:0,他引:17  
描述高原鳅属鱼类2新种,即鼻须高原鳅Triplophysa nasobarbatula sp.nov.和贞丰高原鳅Triplophysa zhenfengensis sp.nov.,采自贵州省荔波县和贞丰县(均属西江水系)。前者与云南高原鳅Tripliophysa yunnanensis Yang相似,后者与鼻须高原鳅Triplophysa nasobarbatula sp.nov.相似,正模标本均保存在遵义医学院生物学教研室。  相似文献   

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