基于Cyt b基因全序列鼩鼱属分子系统学分析——我国东北地区鼩鼱属物种的系统发生地位

利用mtD NA的Cyt b基因全序列对39个鼩鼱属物种的系统分化进行分析,其中包括我国东北地区具有的9个鼩鼱属物种。计算了遗传距离和构建了系统进化树。分子系统学分析支持鼩鼱属应该分为主要分布于古北区的亚属和主要分布于新北区的亚属。Sorex亚属包括分布在古北区的鼩鼱属物种和分布在全北区的苔原鼩鼱和姬鼩鼱,以及分布在新北区的北极鼩鼱。Otisorex亚属包括分布在新北区的鼩鼱属物种和分布在古北区的堪察加鼩鼱和弗兰格尔鼩鼱。特氏鼩鼱-索绪尔鼩鼱类群高度特化,支持其与Otisorex亚属具有更近的系统进化关系。本文探讨了我国东北地区具有的9个鼩鼱属物种的系统分化和分类学问题,进而明确了其在鼩鼱属的系统发生地位。支持姬鼩鼱为全北区物种。扁颅鼩鼱在系统发生地位上较为特化。支持栗齿鼩鼱属于XY_1Y_2性染色体复杂种组。大鼩鼱是东北分布的鼩鼱属物种中最特化的一个物种。我国东北分布和日本北海道分布的细鼩鼱属于不同亚种。

Molecular Phylogenetic Analysis on Species of Sorex Based on Complete Sequences of Cyt b Gene-Phylogenetic Status of Sorex Species in Northeast China

The phylogeny of 39 species of Sorex was analyzed by using the complete sequence of Cyt b gene of mtDNA,including 9 species of Sorex recorded in northeast China.The genetic distance was calculated,and the phylogenetic tree was constructed.The molecular phylogenetic analyses support division of Sorex into a subgenus(Sorex)mainly distributed in the Palearctic and a second subgenus(Otisorex)mainly distributed in the Nearctic.Sorex subgenus would include Sorex species of the Palearctic,viz.S.tundrensis and S.minutissimus of the Holarctic,and S.arcticus of the Nearctic.The Otisorex would include the species of Sorex of the Nearctic,and S.camtschatica and S.portenkoi of the Palearctic.The S.trowbridgii-S.saussurei group is highly specialized and showed a closer phylogenetic relationship with the Otisorex subgenus.The phylogenetic differentiation and taxonomy of the 9 species of Sorex from northeast China are further discussed and their phylogenetic status is clarified here.We document support for inclusion of S.minutissimus among the Holarctic species.S.roboratus proved to be specialized in phylogenetic status.S.daphaenodon belonged to a group of the XY 1Y 2 sex chromosome complex.S.mirabilis proved the most specialized species of Sorex from northeast China.S.gracillimus of northeast China and Hokkaido,Japan,proved to be a separate subspecies.