Hyperacrius Miller, 1896 . N. Am. Fauna, 12:54.

TYPE SPECIES: Arvicola fertilis True, 1894 .

COMMENTS: Taxonomy, geographic distribution, and ecology reviewed by Phillips (1969). According to Corbet (1978c), phylogenetically near Alticola but more fossorial, and assigned to Clethrionomyini by Hooper and Hart (1962) and Gromov and Polyakov (1977).