中文摘要：

利用线粒体COI基因序列，比较了千岛湖水库共栖的细鳞鲴（Xenocypris microlepis）和黄尾鲴（xdavidi）的遗传资源状况。结果显示，在532bp的一致序列中，黄尾鲴碱基T、C、A、G平均含量分别为27．3％、18．0％、28．7％、26．0％；细鳞鲴分别为25．2％、19．6％、29．3％、25．9％。黄尾鲴种群的变异位点为5个，细鳞鲴种群变异位点为3个。多样性分析显示，黄尾鲴的遗传多样性高于细鳞鲴。在两个物种中各发现4个单倍型，黄尾鲴4个单倍型中，有3个是共享单倍型，而细鳞鲴中仅1个共享单倍型，黄尾鲴富文和临岐群体之间存在显著的分化（Fst=0．04809），细鳞鲴汾口群体和富文（Fst=0．23810）、临岐群体（Fst=0．26072）之间存在显著的遗传分化。单倍型的NJ树将四个单倍型分为两个支，推测可能是由于二次迁入或者多样性丧失导致。

英文摘要：

Population genetic structure between Xenocypris microlepis and X. davidi in Qiandao Lake was compared base on mitochondrial COI gene. In the 532 bp sequences, the average nucleotide composition of T, C, A, G of X. davidi were 27.3% , 18.0% , 28.7% and 26. 0% , and X. microlepis were 25.2% , 19. 6% , 29.3% and 25.9%. We detected five variable sites in X. davidi population and three variable sites in X. microlepis population. Genetic diversity shows that X. davidi population possessed higher level of genetic diversity than X. microlepis. There were four haplotypes of each species, and three of them were shared by X. davidi, while only one was shared by the differentiation of X. microlepis. The differentiation of X. davidi among the Fuwen and Lingqi was very obviously （ Fst = 0. 048 09 ）. obvious differentiation of X. microlepis can be found between Fenkou and Fuwen （Fst = 0. 238 10）, Fenkou and Lingqi （Fst = 0. 260 72）. NJ tree divided the four haplotypes into two branches, which may caused by second migration or diversity loss.