Melanomys Thomas, 1902 . Ann. Mag. Nat. Hist., ser. 7, 10:248.

TYPE SPECIES: Oryzomys phaeopus Thomas, 1894 (= Hesperomys caliginosus Tomes, 1860).

COMMENTS: Oryzomyine. A morphologically distinctive group usually arranged as a subgenus of Oryzomys since Goldman's (1918) revision (e.g., Tate, 1932e; Ellerman, 1941; Cabrera, 1961; Hall, 1981). Allen (1913), however, provided morphological criteria, as contrasted to the type species (= Mus palustris) of Oryzomys, defending his retention of Melanomys as a genus; its synonymy in Oryzomys proper deserves more rigorous, character-based, phylogenetic substantiation. The taxon has not been revised; the nominal species listed stem from Cabrera (1961), who acknowledged his solely literature-based interpretation as provisional.