新疆两种裂腹鱼形态学和COI基因的比较分析

运用多变量形态度量学方法结合线粒体COI基因序列,比较分析了新疆和田河两支流（喀拉喀什河、玉龙喀什河）塔里木裂腹鱼（Schizothorax biddulphi）和厚唇裂腹鱼（S.irregularis）的遗传差异。对这两种鱼67尾的31个测量指标进行分析,其中5个性状表现出极显著差异（P〈0.01）,6个性状表现出显著差异（P〈0.05）。在主成分散点图中,这两种裂腹鱼个体间存在交叉现象,没有明显界限,二者外部形态差异较小,难以有效区分。分析了627bp的COI基因序列碱基组成,均表现为G碱基含量最低而C碱基含量最高,A＋T含量大于C＋G含量。26尾塔里木裂腹鱼和厚唇裂腹鱼共检测到6种单倍型和5个核苷酸多态位点,其单倍型多样度分别为0.733和0.556,核苷酸多样度分别为0.00158和0.00089,其中417bp处的C/T转换为二者特有。

Morphological and COI Sequences Analysis of Two Schizothoracinae Fishes in Xinjiang

Genetic variations in Schizothorax biddulphi and S.irregularis collected from two branches of Hotan River（Kalakashi River and Yulongkashi River）were analyzed using the morphological method combined with mtDNA COI gene sequences analysis.Thirty-one measurements of truss networks in 67 individuals of the two species was conducted,in which 5 morphological indices were very significantly different（P0.01） and 6 were significantly different（P0.05）.Scatter plots of scores on the first and second morphological characters of two Schizothoracine fishes showed the individuals were not distinguished definitely because of the unobvious boundaries and overlap in characters.The analysis of 627bp COI gene sequences revealed that the G base content was the minimal while the C base content the maximal,the A＋T content higher than the C＋G content.There were 6 haplotypes and 5 variable nucleotide positions in COI gene fragments in 26 individuals of the two Schizothoracine fishes.The haplotype diversities were found to be 0.733 and 0.556,nucleotide diversities 0.00158 and 0.00089,respectively.The C/T transition in 417bp was unique in two species.