云南怒江高原鳅属鱼类一新种记述

2000年7月和2004年7月，分别在云南省怒江傈僳族自治州和保山市怒江干流采集到一批高原鳅标本。经鉴定，为高原鳅属Triplophysa一未经发表的新种。新种怒江高原鳅Triplophysa(Triplophysa)nujiangensa sp．nov．在形态特征和食性方面与唐古拉高原鳅、斯氏高原鳅、粗唇高原鳅和细尾高原鳅较为相似。本新种身体相对短圆，头部近圆筒形，吻端钝圆，颊部正常，吻部在鼻孔之前明显向下倾斜，下颌铲状，边缘锐利而水平，上唇缘无突起，下唇中央中断，后部无突起，眼间隔稍隆起，眼问距为尾柄高0．6～0．8倍，第一鳃弓内侧鳃耙10～19，肠绕折3个环，前背长为体长71．1％～77．2％，体长为头长4．6．5．5倍，偶鳍短圆，背鳍分枝鳍条8根，胸鳍分枝鳍条10～11根，腹鳍末端不达肛门，尾鳍高度向尾鳍方向不明显降低，尾柄起点处的宽小于该处的高，尾柄长为尾柄高1．6～2．8倍，胸鳍长为胸腹鳍起点间距47．5％～63．5％，尾鳍内凹。本文列出了中国高原鳅属5种铲状下颌种类的检索表，本新种可藉之与这些相似种相区别。

A New Fish Species of Genus Triplophysa (Balitoridae) from Nu Jiang,Yunnan,China

A loach Triplophysa (Triplophysa) nujiangensa sp.nov.(Holotype:KIZ 20007496,61.1 mm SL) has been recognized on basis of two series of collections from main stem of Nu Jiang (Salween) in Nujiang Prefecture,July 2000 and Baoshan City,Yunnan,China,July 2004.Triplophysa (T.) nujiangensa is closely related to T.(T.) tanggulaensis (Zhu),T.(T.) stoliczkae (Steindachner),T.(T.) crassilabris Ding and T.(T.) stenura (Herzenstein).It can be distinguished from T.(T.) stenura,which also occurs in upper Nu Jiang,by following characters:caudal-peduncle depth not decrease prominently vs decrease prominently;caudal-peduncle width is smaller than its depth vs larger than;caudal-peduncle length 1.6-2.8 times its depth vs 4.7-9.5 times;papillae-like process on edge of upper lip absent vs present and form a prefringe;papillae on lower lip absent vs present.It can be distinguished from T.(T.) crassilabris by following characters:branched dorsal fin ray 8 vs 7;branched pectoral fin ray 10-11 vs 8-9;gill rakers 10-19 vs 8-9;intestine loops 3 vs 4-5;lower lip interrupted vs continuous;interorbital space convex vs flat;interorbital width 0.6-0.8 times caudal-peduncle length vs almost equal to;predorsal length 71.1%-77.2% standard length vs about 50%;pelvic fin not reach anus vs reach or surpass;caudal fin emarginate vs truncate.Its spade-like lower jaw with sharp and straight edge is closer to T.(T.) stoliczkae,while its snout bending down anterior to nostril is closer to T.(T.) tanggulaensis;its gill rakers 10-19,just between T.(T.) stoliczkae and T.(T.) tanggulaensis.It can be distinguished from both T.(T.) stoliczkae and T.(T.) tanggulaensis by the following characters:predorsal length 71.1%-77.2% standard length vs 47%-55% and 52%-57%;pelvic fin not reach anus vs reach.It can be further distinguished from T.(T.) tanggulaensis by its snout round vs pointed,cheek normal vs inflated,standard length 4.6-5.5 times head length vs 4.1-4.5,pectoral fin length 47.5%-63.5% distance between pectoral and pelvic fin origins vs about 75%.It has relative smaller body size than T.(T.) stoliczkae,standard length 45.6-73.1mm vs 35.5-111 mm;and it can be further distinguished from T.(T.) stoliczkae by its body short vs slender,head more cylindral vs more triangular,snout bends down anterior to nostril vs head back straight,papillae-like process on edge of upper lip absent vs present and form a prefringe,papillae on lower lip absent vs present,paired fins rounded and short vs sharp and elongate.A key to Chinese Triplophysa with a spade-like lower jaw is listed in the text.