The Shrew of Nagaland: A Remarkable New Genus and Species from Northeast India, With A Discussion of The Phylogeny and Classification of The Soricidae (Mammalia)

A new genus and species of extant shrew, Nagasorex albidens, is described based on a single specimen obtained in Nagaland, northeastern India, in 1950. The new species shows novel characters, such as a total tooth number of 34, not found in any extant genus though they are found in extinct genera such as †Miosorex, †Lartetium, †Pseudotrimylus, and †Domnina. To determine the phylogenetic relationships of the new species, we first analyzed craniodental characters from all extant and many extinct genera of Soricidae. Although statistical support for most nodes was low, the nearest relatives of the new taxon appear to be certain Miocene and Pliocene taxa from Europe and Asia—†Dobenflorinia (new name), †Clapasorex, †Miosorex, and †Crocidosorex—followed by the extant African genera Congosorex, Myosorex, and Surdisorex, all of which we treat as members of the Myosoricinae. We then conducted a molecular phylogenetic study of extant genera using mitochondrial and nuclear genes. Although the genetic data we obtained from the new shrew are limited, our results place Nagasorex as the sister taxon of Crocidurinae (mitochondrial genes), or sister to Myosoricinae + Crocidurinae (nuclear genes). We tentatively place the new genus in the Myosoricinae. Additionally, we replace the preoccupied generic name Soricella with a new name, Dobenflorinia. Based on these results, we present a new systematic arrangement of the Soricidae.