Peromyscus fraterculus Miller 1892

Peromyscus fraterculus Miller 1892, Am. Nat., 26: 261.

Type Locality: USA, California, San Diego Co., Dulzura.

Vernacular Names: Northern Baja Deermouse.

Synonyms: Peromyscus herroni (Rhoads 1893); Peromyscus homochroia Elliot 1903; Peromyscus nigellus (Rhoads 1894); Peromyscus propinquus J. A. Allen 1898 .

Distribution: SW California, USA, through Baja California Norte, to EC Baja California Sur, México.

Discussion: P. eremicus species group. Long considered a geographic race of P. eremicus following the revision of Osgood (1909; e.g., also and Hall, 1981, Lawlor, 1971 a). Studies of allozymic (Avise et al., 1974) and mitochondrial DNA variation (Walpole et al., 1997) within eremicus as conceived by Osgood have intimated that western and eastern moieties are specifically distinct. Riddle et al. (2000 a, c) have confirmed this pronounced genetic divergence, reinstated fraterculus to species, demonstrated its common ancestry with P. eva, and interpreted its Pleistocene origination in a phylogeographic context. Synonyms follow Riddle et al. (2000 c).