Dicrostonyx Gloger, 1841 . Hand. Hilfsb. Nat., 1:97.

REVIEWED BY: M. L. Johnson (MLJ).

COMMENT: This genus is more complex than previously believed; see Rausch and Rausch, 1972, Z. Saugetierk., 37: 372-384; Rausch, 1977, in Sokolov, ed., [Adv. Mod. Theriol.], Acad. Sci. U.S. S.R., Nauka, Moscow, pp. 162- 177; compare with Corbet, 1978:96, and Hall, 1981:835-837. Many previously nominate subspecies are here considered full species. According to experimental breeding and karyotypic evidence the torquatus group represents a superspecies comprising at least nine allospecies (MLJ). The geographically isolated taxon nunatakensis was described as a subspecies of torquatus by Youngman, 1967, Proc. Biol. Soc. Wash., 80:31-34, and listed as a subspecies of groenlandicus by Hall, 1981:836. It is morphologically distinct from geographically adjacent kilangmiutak and rubricatus; see Youngman, 1975, Mammals of the Yukon Terr., Natl. Mus. Can. Publ. Zool., 10: 116, and is here left unassigned; known only from the Ogilvie Mtns., C. Yukon (Canada) (RSH). Two subgenera ( Dicrostonyx and Misothermus) have been recognized; D. hudsonius represents the latter. Placed in tribe Dicrostonyxini by Gromov and Polyakov, 1977:177.

ISIS NUMBER: 5301410008073000000.