摘要
A new species of the subfamily Labeoninae, Garra nujiangensis Chen and Yang, sp. nov. is recognized from a secondary branch of Nujiang River (upper Salween) in Zhenkang county, Yunnan province, China. It can be distinguished from other beardless Garra species by the following combination of characters: 12 - 14 circumpedunele scales; 48 - 50 lateral- line scales; a pair of rudimentary rostral barbels present in little individuals; 8 - 9 branched dorsal-fin rays; 5 - 6 scales between dorsal-fin origin and lateral line and 3 - 4 scales between pelvic-fin origin and lateral line; caudal peduncle relatively stouter; length between snout tip to posterior margin of eye longer than body depth at anal fin origin; head length longer than body depth at dorsal fin origin; prepelvic length 50.0% - 53.7% of standard length; pre-anus length 58.9% - 63.9% of standard length; body width 16.7% - 19.6% of standard length; body depth at dorsal fin 19.2% - 22.6% of standard length. The present study also verified that the presence of tiny barbells is a juvenile character in some beardless Garra species, such as G. nujiangensis and G. alticorpora.
2003年4月,于怒江二级支流镇康县境内的大叉河中采获一批墨头鱼属(Garra)鱼类标本,经鉴定为一新种,命名为怒江墨头鱼(G. nujiangensis Chen and Yang, sp. nov.)。该新种主要鉴别特征:围尾柄鳞12~14;侧线鳞48~50;在小个体中有一对微小的吻须;背鳍分支鳍条8~9;侧线上鳞5~6,侧线下鳞3~4;体高小于头长;臀鳍起点处的小于眼后至吻端的距离;腹鳍前长为体长的50.0%~53.7%;肛门前长为体长的58.9%~63.9%;体宽为体长的16.7%~19.6%;体高为体长的19.2%~22.6%。本研究证实,在缺须的墨头鱼属的一些物种中,如高体墨头鱼(G. alticorpora)和怒江墨头鱼(G. nujiangensis),其幼体中往往具有一对很小的吻须。
基金
国家自然科学基金(40601096
30870291
30730017)
国家重点基础研究发展计划(九七三计划)项目(2003CB415105)
云南大学理(工)科校级科研项目(2008YB004)