Multilocus phylogeny and cryptic diversity of white-toothed shrews (Mammalia, Eulipotyphla, Crocidura) in China

AbstractBackground:Crocidura, the most speciose mammalian genus, occurs across much of Asia, Europe and Africa. The taxonomy of Chinese representatives has been studied primarily based on cursory morphological comparisons and their molecular phylogenetic analyses remain unexplored. In order to understand the phylogeny of this group in China, we estimated the first multilocus phylogeny and conducted species delimitation, including taxon sampling throughout their distribution range.Results:We obtained one mitochondrial gene (cytb) (~ 1, 134 bp) and three nuclear genes (ApoB,BRCA1,RAG1) (~ 2, 170 bp) for 132 samples from 57 localities. Molecular analyses identified at least 14 putative species that occur within two major well-supported groups in China. PolyphyleticC. wuchihensisappears to be composed of two putative species. Two subspecies,C. rapax rapaxandC. rapax kurodaishould be elevated to full species status. A phylogenetic tree based on mitochondrial gene from AsianCrociduraspecies showedthat theC. rapax rapaxis embedded withinC. attenuata, making the latter a paraphyletic group.Three strongly supported undescribed species (C.sp.1,C.sp.2 andC.sp.3) are revealed from Zada County of Tibet (Western China), Hongjiang County of Hunan Province (Central China) and Dongyang County of Zhejiang Province (Eastern China), Motuo County of Tibet, respectively. The divergence time estimation suggested that China’sCrociduraspecies began to diversify during the late Pliocene (3.66 Ma) and the Early Pleistocene (2.29 Ma), followed by a series of diversifications through the Pleistocene.Conclusions:The cryptic diversity found in this study indicated that the number of species is strongly underestimated under the current taxonomy. We propose that the three undescribed species should be evaluated using extensive taxon sampling and comprehensive morphological and morphometric approaches. Climate change since the late Pliocene and the uplift of the Qinghai-Tibet Plateau may result in the diversification and speciation of China’sCrociduraspecies. In short, the underestimated diversity underlines the need for a taxonomic revision of ChineseCrociduraspecies.