基于线粒体ND2基因的直翅目部分种类分子系统发育分析

测定了39种直翅目昆虫线粒体ND2基因全长序列,联合GenBank中41种直翅目昆虫的ND2基因序列,探讨ND2基因在解决直翅目系统发育分析上的功效,为建立直翅目的主要类群之间稳定的系统发育关系提供更多的数据。研究结果表明,直翅目昆虫的ND2基因序列全长为996～1 029 bp,平均长度为1 020 bp,A+T含量平均为73%。用贝叶斯法(Bayesian,BI)、最简约法(maximum parsimony,MP)和最大似然法(maximum likelihood,ML)构建系统树,SH检验显示,RAxML法构建的ML树似然值最大,与PAUP*的ML法构建的ML树差异显著,而与贝叶斯树和简约树没有明显差异。所有系统树都显示直翅目为单系群;而蝗亚目的剑角蝗科、网翅蝗科、槌角蝗科和斑腿蝗科均不是单系群,锥头蝗科与瘤锥蝗科亲缘关系较近,这与Otte分类系统一致。螽亚目基本由两大分支构成,一支是蝼蛄总科和蟋蟀总科聚集而成,且具有很高的置信度;另一大分支由螽斯总科独自构成。

The Molecular Phylogenetic Analysis of Some Species of Orthoptera Based on Mitochondrial ND2 Gene

The complete sequences of ND2 gene from 39 Orthoptera species were sequenced in this study and those of 41 species down loaded from GenBank were used to construct the robust phylogenetic relationships of these Orthoptera species and to explore their phylogenetic utility and performance.The results indicated that the complete sequence length of ND2 gene was 996-1 029 bp with average length of 1 020 bp,A+T content was 73%.The SH test of phylogenetic trees reconstructed using four methods showed that the maximum likelihood tree from RAxML method was not significantly different from that of maximum parsimony or Bayesian method,but was significantly different from that of maximum likelihood method using the PAUP*.The Orthoptera showed monophyly,while Acrididae,Arcypteridae,Gomphocerinae and Catantopidae were not monophyletic groups;meanwhile the relationship between Pyrgomorphidae and Chrotogonidae was much closer,which was consistent with the Otte’s classification system,and thus we suggested to merge them as one family.Some disputes still existed on the status of the Pamphagidae.Ensifera was divided into two branches.Gryllotalpidae and Gryllidae were grouped into one clade with high confidence,and the Tettigoniidae was regarded as another independent clade.