鳜类系统发育的线粒体Cytb基因全序列分析

测定了鳜、大眼鳜、斑鳜、暗鳜、波纹鳜、长体鳜、中国少鳞鳜等7种鳜类12个个体的线粒体细胞色素b基因全序列。结合GenBank中的同源序列,共分析了9种鳜类的系统发育关系。序列分析表明,鳜属鱼类属内种间的遗传距离(0.015～0.093)明显小于少鳞鳜属鱼类属内种间的遗传距离(0.152～0.178)。在分子系统发育树上,长体鳜与鳜属的鳜、大眼鳜、斑鳜、波纹鳜、暗鳜聚合成一分支,少鳞鳜属的种类聚成另一分支;支持将长体鳜归入鳜属,鳜类分为鳜属和少鳞鳜属等二个属的分类处理。在鳜属鱼类中,鳜和大眼鳜亲缘关系十分密切;斑鳜与波纹鳜亲缘较近;长体鳜与鳜属其它5个种的亲缘关系较远。在少鳞鳜属鱼类中,中国少鳞鳜和日本少鳞鳜的亲缘关系较远,韩国少鳞鳜的系统位置较不明确。鳜类的单系性及其鳜类的系统位置仍有待进一步研究。

Phylogeny of sinipercine fishes based on complete sequences of mitochondrial cytochrome b gene

Complete sequences of mitochondrial cytochrome b gene of Siniperca chuatsi,S.kneri,S.scherzeri,S.undulata,S.obscura,Coreosiniperca roulei,Coreoperca whiteheadii were sequenced.Combined with available homologous sequences of C.whiteheadi,C.kawamebari and C.herzi and outgroup taxa from GenBank,23 mitochondrial sequences of 17 individuals from 9 species of sinipercine fishes and 6 non-sinipercine species were analyzed to infer phylogenetic relationships among sinipercine fishes.Sequence analysis showed that the genetic distances among Siniperca species,which were from 0.015 to 0.093,were obviously smaller than those of Coreoperca species,which ranged from 0.152 to 0.178.Kimura 2-parameter model based Neighbor-Joining trees showed that sinipercine fishes consisted of a group which were further divided into two clades.Of which one clade included C.roulei and Siniperca,and another were consisted of Coreoperca,supporting the taxonomic treatment that sinipercine fishes could be divided into Siniperca and Coreoperca.Resultant phylogenetic results confirmed the very close relationship between S.chuatsi and S.kneri,showed relatively close relationship between S.scherzeri and S.undulata,and suggested that C.roulei was relatively distantly related to other Siniperca species.The relationships among the three subgroup S.chuatsi-S.kneri,S.scherzeri-S.undulata and S.obscura were not fully resolved yet in this study.In the genus Coreoperca,C.whiteheadii was distantly related to C.kawamebari,and phylogentic position of C.herzi was uncertain.Monophyly and phylogenetic positions of sinipercine fishes remained to be further studied.