贵州北部鮠属(鲇形目,鲿科)的1个新种

A New Species of Leioxassis in Northern Guizhou

2010年7月6日在贵州北部洛安江下游采集到土著鱼类38尾,其中,17尾经鉴定为贵州省鲿科鱼类一新种,定名为遵义小钝吻鮠（Leioxassis microcrassirostris Zunyiensis Xiao sp.nov.）。其眼较大,稍凸出,下缘约占全眼1/3眼缘游离;后鼻孔间距略小于两眼内侧间距;前鼻孔四周有近褐色圆形斑状沉淀;在胸鳍基部后缘与背鳍基部前缘中部体两侧各有一暗色斑状沉淀,稍大于前鼻孔处褐色斑状沉淀;背鳍I-6-7,胸鳍I-7-8,腹鳍6,臀鳍16,尾鳍内凹形、上下2叶等长,外缘圆钝;全长93-124mm,体长为尾柄高的8.9-11.6倍;头长为吻长的2.56-3.65倍,为眼径的4.9-6.53倍,为眼间距的1.66-2.04倍;尾柄长为尾柄高的1.56-2.11倍。

17 fish of 38 fish collected from the lower reaches of Luo＇an river in northern Guizhou province were identified as a new species of Bagridae family,which was named Leioxassis microcrassirostris.One third of its large bulgy eyes at the lower edge are dissociative.The distance between postnaris is slightly less than that of eyes.Round porphyrotopic brown sediment can be found around prenaris which was a little smaller than the melanocratic porphyrotopic sediment at both sides of the middle part between trailing edge of pectoral fin base and leading edge of dorsal fin base.Rays of dorsal fin,pectoral fin,pelvic fin and anal fin are I-6-7,I-7-8,6 and 16,respectively.The total length of inner sunken tail fin with round blunt outer edge and 2 lobes of equal length is 93~124 mm,which is 8.9~11.6 times the height of caudal peduncle.Head length is 2.56~3.65 times the length of snout,4.9~6.53 times the diameter of eys and 1.66~2.04 times the distance between eyes.The length of caudal peduncle is 1.56~2.11 times the height of caudal peduncle.