中文摘要：

对采于青海省玛柯河的6尾黄石爬（鱼兆）和四川省都江堰的1尾青石爬（鱼兆）线粒体DNA细胞色素b（Cyt b）基因进行了PCR扩增并进行序列测定。结果表明,黄石爬（鱼兆）6个个体均属同一单倍型。在Cyt b基因全长1140 bp中,2种鱼类存在29个变异位点（2.54%）,其中23个（79.3%）突变位点为转换,6个（20.7%）突变位点为颠换。2种鱼类序列差异偏低,提示分化较晚,致使物种间在Cyt b基因上未能积累丰富的碱基变异。黄石爬（鱼兆）遗传多样度较低,可能与其栖息环境的改变有关。

英文摘要：

In the present study,the complete sequences of mitochondrial cytochrome b gene（Cyt b）were sequenced for 6 individuals of Euchiloglanis kishinouyei from Make River and 1 individual of E.davidi from Dujiangyan.The results showed that all the six individuals of E.kishinouyei belonged to one haplotype.Among the 1140 bp of sequences,29（2.54%）nucleotide sites were variable between the haplotypes of the two species.Of the variable sites,23（79.3%）were transitions and 6（20.7%）were transversions.The percent sequence divergence was found to be low between the two species,indicating that the divergence of E.kishinouyei and E.davidi was evolved late,there being no formation of abundant variations in the Cyt b.The low genetic variation in E.kishinouyei may be related with the sequence characteristics changes in their habitat environment.