蝗总科部分种类16S rDNA的分子系统发育关系

Molecular Phylogeny of Some Species of the Acridoidea Based on 16S rDNA

将自测的我国直翅目蝗总科 8科 8个种和从互联网GenBank中检索到相关物种的线粒体基因组 16SrDNA序列片段进行同源性比较 ,计算核苷酸使用频率 ,并构建分子系统树。在获得的 4 80bp的序列中 ,A +T约占70 7% ,G +C为 2 9 3% ,颠换取代 (transversion)的速率大于或接近转换取代 (transition)的速率 ,其中 188个核苷酸位点存在变异。研究结果表明 :在直翅目蝗总科有差异的 188bp中 ,属内种间的碱基序列差异仅为 1 5 % ,科内属间为 3 5 %～ 3 6 % ,科间差异为 4 8%～ 15 8% ,亚目间差异达到 15 2 %～ 2 5 6 %。分子系统树表明 :科内的属和属内的种均优先聚在一起 ;蝗总科 8科的起源关系为 :锥头蝗科→瘤锥蝗科→癞蝗科→斑翅蝗科→剑角蝗科→网翅蝗科和槌角蝗科→斑腿蝗科 ;锥头蝗科与瘤锥蝗科关系较近 ,是蝗总科内最原始的类群 ;槌角蝗科和网翅蝗科互为姐妹群 ,与最进化的斑腿蝗科关系较近 ;蚤蝼科为独立的一支 ,最先分出 ,似为一个亚目 ,与现用的分类系统有明显差别 ;哈螽科 (螽总科 )和蟋蟀科聚在一起为剑瓣亚目 (Ensifera) ,蚱科和蝗总科的 8科组成短瓣亚目 (Caelifera) ,同现用的分类系统。

Based on the 16S rDNA of 8 species (belonging to 8 families of Acridoidea) from China and keyed to 8 relative species of Orthoptera from GenBank,the homologus sequences were compared.The used frequency of nucleotide was calculated and the molecular phylogenetic tree constructed by MEGA microsoft.In the 480 bp fragment of mitochondial 16S rDNA,A+T was about 70.7% and G+C only 29.3%.The sequence data revealed considerable variation in 188 nucleotide sites among the analyzed individuals from 8 different families.The variation rate of transversion was larger than or approach to transition.The results showed that the ranges of the 16S rDNA nucleotide divergence within species,among species of a genus,among genera of a family,and among the same family and suborder were 1.5%,3.5%～3.6%,4.8%～15.8% and 15.2%～25.6%,respectively.The members of the same genus and family were grouped together.The phylogenetic relationships of 8 families were Pyrgomorphidae→Chrotogonidae→Pamphagidae→Oedipodidae→Acrididae→Arcypteridae→Gomphoceridae→Catantopidae.Pyrgomorphidae had closer relationships with Chrotogonidae as well as being the most ancestral group.Arcypteridae and Gomphoceridae were the sister groups and had closer relationships with most evolutionary Catantopidae.Tridactylidae was divided firstly as a suborder,which differs from the recent taxonomy distinctly.Haglidae (Tettigonoidea) and Gryllidae were grouped into suborder Ensifera,Tetrigidae and 8 families of Acridoidea were grouped into suborder Caelifera,as same as recent taxonomy.