| Popis: |
Background: Crocidura, the most speciose mammalian genus, occurs across much of Asia, Europe and Africa. In China, the taxonomy has been primarily based on cursory morphological comparisons and molecular phylogenetic relationships of the genus remain unexplored. In order to understand the phylogeny of this group in China, we estimated the first multi-loci phylogeny and conducted species delimitation, including taxon sampling throughout their distribution range.Results: We obtained one mitochondrial gene (~ 1, 134 bp) and three nuclear genes (~ 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. Polyphyletic C. wuchihensis appears to be composed of two putative species. Two subspecies, C. rapax rapax and C. rapax kurodai should be elevated to full species status. A phylogenetic tree based on mitochondrial gene from Asian Crocidura species showed that C. rapax rapax was found embedded within C. attenuate, making the latter a paraphyletic group. Three strongly supported cryptic species are revealed from Motuo of Xizang, Zada of Xizang, Hunan and Zhejiang. The divergence time estimation suggested that China’s Crocidura species began to diversify during the late Pliocene (3.70 Ma) and the Early Pleistocene (2.33 Ma) periods, followed by a series of diversifications through the Pleistocene period.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 cryptic species should be evaluated using extensive taxon sampling and comprehensive morphological and morphometric approaches. Climate change since the late Pliocene periods and the uplift of the Himalayas may have resulted in the diversification and speciation of China’s Crocidura species. In short, the underestimated diversity underlines the need for a taxonomic revision of China’s Crocidura species. |
