Antarctic Isopods

The phylogenetic relationships of 14 species of the Antarctic amphipod families Epimeriidae and Iphimediidae were investigated using 553 bp of the gene for the mitochondrial cytochrome oxidase subunit I (COI) and 98 morphological characters. Both families are dominant members of the Antarctic benthic amphipod community. In contrast to previous studies, our molecular and morphological data suggest that the families Epimeriidae and Iphimediidae may not be sister taxa. Our study suggests that Iphimediidae are more closely related to Eusirus (Eusiridae) than to Epimeria (Epimeriidae). Phylogenetic analyses based on maximum parsimony (MP) and maximum likelihood (ML) indicate that the genera Iphimediella and Gnathiphimedia are not monophyletic.本研究针对南极端足类叶钩虾科（Epimeriidae）与强螯钩虾科（Iphimediidae）的14个物种的系统发育关系展开探究，采用线粒体细胞色素氧化酶亚基I（COI）基因的553 bp片段与98个形态学特征进行分析。两科均为南极底栖端足类群落中的优势类群。与既往研究不同，本研究的分子与形态学数据表明，叶钩虾科与强螯钩虾科可能并非姐妹类群。本研究提出，强螯钩虾科与真螯钩虾属（Eusirus，隶属于真螯钩虾科Eusiridae）的亲缘关系要近于其与叶钩虾属（Epimeria，隶属于叶钩虾科）的亲缘关系。基于最大简约法（MP）与最大似然法（ML）的系统发育分析结果显示，强螯钩虾属（Iphimediella）与颚螯钩虾属（Gnathiphimedia）并非单系类群。