Molecular phylogenetic and phylogeography of Soriculus nigrescens in southwest China

The Himalayan Shrew belongs to the genus Soriculus, which is a monotypic genus. We investigated the phylogeographic patterns, speciation, divergence time, and demographic history of Soriculus nigrescens in southwestern China. A total of 128 samples from 29 regions were analyzed for both mitochondrial and nuclear genes. Phylogenetic analyses of the concatenated mtDNA and nuDNA data revealed three highly divergent lineages within the S. nigrescens. One group represented subspecies S. n. minors, another group represented subspecies S. n. nigrescens, which is made up of two Clades A and B. The species delimitation analyses, based on two methods, supported the species status of the two Clades of S. n. nigrescens. In addtion, it was found that individuals at different altitudes in Motuo were divided into two Clades. Bayesian skyline plotting analyses and ecological niche modeling also supported demographic and range expansions during the LGM for S. n. nigrescens. We propose that S. n. nigrescens appears to be composed of two putative species, and S. n. minor should be elevated to species status. Our study also suggested that climate change since the Miocene periods and the uplift of the QTP may have resulted in the diversification and speciation of S. nigrescens.