Clethrionomys Tilesius, 1850 . Isis, 2:28.

TYPE SPECIES: Mus rutilus Pallas, 1779 .

SYNONYMS: Craseomys, Glareontys, Eotomys, Euotomys, Evotontys, Neoaschizontys.

COMMENTS: Placed in tribe Clethrionomyini, usually with voles such as Eothenomys, Alticola, and Hyperacrius (Koenigswald, 1980; Kretzoi, 1969). Clethrionontys is perhaps most closely related to Eothenomys, if not congeneric with it as suggested by some authors (Corbet, 1978c, 1984; Hooper and Hart, 1962). Large segments of the genus were taxonomically reviewed by Aimi (1980), Corbet (1978c, 1984), and Gromov and Polyakov (1977); chromosomal data summarized and interspecific relationships discussed by Gamperl (1982), Modi and Gamperl (1989), Nadler et al. (1976); Sokolov et al. (1990), and Vorontsov et al. (1978); electrophoretic data presented by Nadler et al. (1978) and Chaline and Graf (1988). The relationship among European and Japanese species based on living and Pleistocene samples was monographed by Kawamura (1988).

Species in this genus were commonly listed under Evotomys (e.g., Hinton, 1926) until Palmer (1928) established the priority of Clethrionomys . Recently, Pavlinov and Rossolimo (1987) have questioned whether Myodes is a senior synonym of Clethrionomys and Zagorodnyuk (1990) employed the former name. This issue warrants prompt settlement before the literature on red-backed voles is diffused under yet another generic name.