Oryzomys capito (Olfers, 1818) . In Eschwege, J. Brasilien, Neue Bibliothek. Reisenb., 15:209.

TYPE LOCALITY: Paraguay, San Ignacio Guazu .

DISTRIBUTION: S Venezuela and Guianas, Brazil and Amonzonian regions of Colombia, Ecuador, Peru, and Bolivia.

SYNONYMS: cephalotes, goeldi, laticeps (of Lund, 1841), modestus, perenensis, saltator, velutinus .

COMMENTS: Taxonomic understanding of this species embroiled by the infelicitous footnote of Hershkovitz (1960:544), who suggested the synonymy of some 20 taxa under O. capito, an opinion expanded by Cabrera (1961) and followed by other authors (e.g., Handley, 1966a, 1976). The extremeness of this viewpoint was seriously challenged by the karyotypic study of Gardner and Patton (1976); as a result, the following forms considered synonyms by Hershkovitz (1960) and /or Cabrera (1961) are now acknowledged as distinct species or as synonyms of other species (see separate accounts): O. intermedius, O. legatus, O. macconnelli, O. nitidus, O. oniscus, rivularis (of O. bolivaris), O. talamancae, and O. yunganus . As with other names based on Azara's (1801) characterizations, the clear fixation of this name to a species morphology and the proper usage of megacephalus Fischer, 1814, versus capito Olfers, 1818, should be formally established.