Sigmodon arizonae Mearns, 1890 . Bull. Am. Mus. Nat. Hist., 2:287.

TYPE LOCALITY: USA, Arizona, Yavapai Co., Fort Verde .

DISTRIBUTION: Extreme SE California and SC Arizona, USA, south in W Mexico to Nayarit.

STATUS: IUCN - Endangered as S. a. plenus.

SYNONYMS: cienegae, jacksoni, major, plenus.

COMMENTS: Chromosomal and morphological differences have revealed the specific distinction of S. arizonae and S. hispidus (see Zimmerman, 1970; Severinghaus and Hoffmeister, 1978; Elder and Lee, 1985).