Taxonomic position of Chinese voles of the tribe Arvicolini and the description of 2 new species from Xizang, China.

China has 26 species in the tribe Arvicolini. The taxonomic status of these voles remains controversial despite much effort. Herein, we evaluate the taxonomic position of 22 species plus 2 unidentified taxa using mitochondrial DNA gene sequences (). We also evaluate 18 species and 2 unidentified taxa using morphological data. Phylogenetic analyses of resolve monophyly for the genera , , , , , and with strong support. clusters with but with very weak support. Analyses of concatenated resolve the same genera with strong support, but the topology of the tree differs from that of in that roots at the base of the tree independent of , which forms the sister-group of in a more terminal position. The matrilineal genealogy excludes the type species from the rest of the Arvicolini. This species forms the sister-group of with high support. includes , , , , , , and 2 unidentified specimens. includes the former species , , , , and . Finally, has the subgenera , s, , , , and , which includes the Chinese species , , and . General mixed Yule-coalescent species delimitation modeling demarcates 6 currently recognized species and 2 new species of . A principal component analysis of the morphological data among 7 matrilines shows that all variables have positive loadings of high magnitude on the 1st component. Canonical discriminant analysis for (including and 2 unidentified species) correctly classifies 93.0% of specimens. Overall, our analyses support the recognition of , , , , , and as genera. includes , and the genealogical position of remains uncertain. The status of requires further study. We assign to and describe 2 new species of .