西藏雅鲁藏布江下游墨头鱼属一新种(鲤形目:鲤科)

A New Species of Genus Garra(Cypriniformes: Cyprinidae) from the Lower Yarlung Tsangpo River Drainage in Southeastern Tibet, China

2016年11月,于西藏自治区墨脱县雅鲁藏布江支流哈果河中采集到一批墨头鱼属鱼类标本,经鉴定为一新种,命名为西藏墨头鱼(Garra tibetana sp. nov.)。该种曾一度被误认为Garra kempi Hora1921。经形态对比,该新种与G.kempi及同属其他近似物种的主要鉴别特征包括:吻部具微弱额突,吻前端横叶及两侧有若干角质单尖棘突;胸腹部均有鳞片覆盖;背鳍分枝鳍条7?～8?,臀鳍分枝鳍条4?;侧线鳞39～42,背前鳞13～14,围尾柄鳞12～13;体高为体长的13.5%～17.6%,尾柄高为体长的8.8%～11.0%,肛门至臀鳍起点为腹鳍起点至臀鳍起点距离的47%～56%。

An ichthyological survey for the lower Yarlung Tsangpo River drainage in November 2016found a new species of Garra,which is described in this study.Garra tibetana sp.nov.,a new species of the subfamily Labeoninae,family Cyprinidae,is recognized from the Haguo River,a tributary of the Yarlung Tsangpo River in Motuo County,southeastern Tibet.The holotype and paratypes are both deposited at the Museum of Aquatic Organisms,Institute of Hydrobiology (IHB),Chinese Academy of Sciences,Wuhan, China.This species was once misidentified as Garra kempi Hora 1921for a long period.It is distinguished from G.kempi by having a faint proboscis,the chest covered by scales,fewer branched anal-fin rays,a shallower body and a more slender caudal peduncle.In addition,based on the morphological data (Table 1),it could be distinguished from related congeners of Garra primarily by the following combination of characters: having a faint proboscis on the snout,the transverse lobe and lateral surface of snout covered with several unicuspid tubercles;the chest and belly covered by scales;branched dorsal-fin rays 7 1/2-8 1/2,branched anal-fin rays 4 1/2;lateral-line scales 39-42,predorsal scales 13-14and circumpeduncular scale rows 12- 13;body depth 13.5%-17.6%of standard length,caudal-peduncle depth 8.8%-11.0%of standard length, distance from anus to anal fin 47%-56%of pelvic-anal distance.Principal diagnostic characters for G tibetana and related congeners are shown in Table 2.