Oligoryzomys fulvescens (Saussure, 1860) . Revue Mag. Zool. Paris, ser. 2, 12: 102.

TYPE LOCALITY: Mexico, Veracruz, Orizaba (as restricted by Merriam, 1901:295) .

DISTRIBUTION: W and E versants of S Mexico, through Mesoamerica, to Ecuador, northernmost Brazil, and Guianas in South America.

SYNONYMS: costaricensis, creper, delicatus, engraciae, lenis, mayensis, messorius, munchiquensis, navus, nicaraguae, pacificus, reventazoni, tenuipes .

COMMENTS: All Central American forms retained as subspecies (see Hall, 1981). Variable karyotypic descriptions intimate that more than one species occurs among the listed synonyms (Gardner and Patton, 1976; Haiduk et al., 1979).