中国广西金线鲃属一新种(鲤形目,鲤科,鲃亚科)

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.

A NEW SPECIES OF THE GENUS SINOCYCLOCHEILUS FROM CHINA (CYPRINIFORMES, CYPRINIDAE, BARBINAE)

Sinocyclocheilus xunlensis sp. nov. Holotype No. ASIZB 73169, 129*!mm SL, collec- ted from a cave in Xunle, Huanjiang, Guangxi, China in May 2001. The collection locality belongs to Liu River of Pearl River Basin. Paratype No. ASIZB 73167, 93*!mm SL; ASIZB 73168, 72*!mm SL; ASIZB 73170, 126*!mm SL; ASIZB 73171, 128*!mm SL. The collection time and locality is the same as holotype. All specimens are kept in Fish Collection Room of Institute of Zoology, Chinese Academy of Sciences (ASIZB). D. iii-7; P. i-12(11-13); V. ii-7; A. iii-5. Scales in lateral line 41-48. Gill-rakers 8. Vertebrae 4+36-37. Depth of body in standard length (SL) 3.3-3.8, width of body 7.5-8.0, head length 3.0-3.2, predorsal length 1.7-1.8, caudal peduncle length 5.7 (5.1-6.1), caudal peduncle depth 9.4 (8.8-10.2).Snout length in head length 3.0 (2.9-3.1), interorbital width 4.3 (4.0-4.7). Caudal peduncle depth in its length 1.8 (1.5-1.8). The new species differs from all other known species in the genus Sinocyclucheilus but is similar to S. anophthalmus Chen et Chu, 1988. The two species are different from each other in following characters: 1) the last unbranched dorsal-fin ray of the new species is weak, but S. anophthalmus is strong; 2) the upheaval of the new species in head is behind frontal, but the upheaval of S. anophthalmus is in the middle of frontal; 3) the lateral line of the new species is relative straight, but the one of S. anophthalmus has a curve between ventral fin and anal fin; 4) the pectoral fin length of the new species is longer than S. anophthalmus, exceeding the origin of ventral fin; 5) the distribution of both species is different; in addition, they are different in the same counts as depth and head length in standard length, caudal peduncle depth in its length, number of lateral line scales, vertebrae, etc.