Molecular Phylogeographic Analysis of Chinese White-toothed Shrew in China
Subspecies differentiation of Chinese white-toothed shrew(Crocidura rapax)is controversial.In order to clarify the molecular phylogeographic pattern of C.rapax and provide further molecular biological evidence for taxonomy,this study analyzed the Cyt b gene sequences of C.rapax(20 samples)collected from Guizhou Province in China together with Cyt b gene sequences of C.rapax(19 samples)downloaded from GenBank.The phylogenetic tree was divided into three main clades:C.r.rapax,C.vorax,and C.rapax kurodai.The C.r.rapax is divided into Guizhou,Yunnan,southeast Sich-uan lineage and central and west Sichuan lineage.The results of genetic distance showed that the greatest genetic dis-tance was between central and west Sichuan lineage of C.r.rapax and C.r.kurodai(0.1181),followed by between Gui-zhou,Yunnan,southeast Sichuan lineage of C.r.rapax and C.r.kurodai(0.1174).The genetic distance between two lin-eages of C.r.rapax is 0.0195.A similar geographical patterns was also observed in the median-joining network analysis.The results of median-joining network are consistent with the results of phylogenetic relationships and genetic distance,sup-porting the view that the sample from Taiwan is a separate species,namely,C.tadae.The C.rapax have no subspecies differentiation in China,and can be divided into Guizhou,Yunnan,southeast Sichuan lineage and central and west Sich-uan lineage.Twenty-three haplotypes were found in the 32 samples of C.rapax,and the nucleotide polymorphism was 0.01285.The analysis of population history suggested that C.rapax has experienced population expansion recently,but it is not a single dramatic expansion.
Chinese white-toothed shr-ew(Crocidura rapax)CrociduraMolecular phylogeography