Reithrodontomys gracilis J. A. Allen and Chapman, 1897 . Bull. Am. Mus. Nat. Hist., 9:9.
TYPE LOCALITY: Mexico, Yucatan, Chichen-Itza .
DISTRIBUTION: Yucatan Peninsula and coastal Chiapas, Mexico, south along Pacific watershed to NW Costa Rica.
SYNONYMS: anthonyi, harrisi, insularis, pacificus .
COMMENTS: Subgenus Aporodon, mexicanus species group. See Young and Jones (1984, Mammalian Species, 218).