Reithrodontomys raviventris Dixon, 1908 . Proc. Biol. Soc. Washington, 21:197.

TYPE LOCALITY: USA, California, San Mateo Co., Redwood City .

DISTRIBUTION: Salt marshes around San Francisco Bay, California, USA.

STATUS: U.S. ESA and IUCN - Endangered.

SYNONYMS: halicoetes .

COMMENTS: Subgenus Reithrodontomys, megalotis species group. Morphological and chromosomal differentiation between the subspecies raviventris and halicoetes thought to represent terminal stages of speciation (Fisler, 1965; Shellhammer, 1967). Banded chromosomes and genic data reveal sister-group relationship to R. montanus (Hood et al., 1984; Nelson et al., 1984). See Shellhammer (1982, Mammalian Species, 169).