Abstract
The morphometric relationships among five operational taxonomic units of the Sorex caecutiens/shinto group (Soricidae) (S. caecutiens of Hokkaido, S. shinto shinto of Honshu including the S. chouei holotype, S. s. shikokensis of Shikoku, and S. s. sadonis of Sado) in the Japanese Islands, were examined using uni- and multivariate analyses of 15 cranial, dental, and external characters. The morphological analyses showed that the shrew from Hokkaido (S. caecutiens) and those from Honshu, Shikoku, and Sado (S. shinto) were exclusively differentiated. In particular, the surface structure of the fourth upper premolar completely separated the two taxa. In contrast, S. s. sadonis from Sado could not be completely distinguished from related taxa from Honshu and Shikoku. Thus these morphometric analyses re-confirm that S. caecutiens of Hokkaido, and S. shinto from Honshu, Shikoku, and Sado, should be treated as two separate species, as has previously been proposed on the basis of a molecular phylogenetical study.
