Nectomys squamipes (Brants, 1827) . Het Geslacht der Muizen, p. 138.

TYPE LOCALITY: Brazil, Säo Paulo, Säo Sebastiao (as restricted by Hershkovitz, 1944:32) .

DISTRIBUTION: Basin of the Rios Magdalena and Cauca, NC Colombia; east of the Andes broadly distributed from Guianas, Venezuela, and E Colombia southwards to NE Argentina, Uruguay, and SE Brazil; sea level to 2000 m.

SYNONYMS: amazonicus, apicalis, aquaticus, brasiliensis, cephalotes, fulvinus, garleppii, grandis, magdalenae, mattensis, melanius, montanus, napensis, olivaceus, pollens, rattus, robustus, vallensis.

COMMENTS: Hershkovitz (1944) arrayed most nominal taxa of water rats as subspecies of N. squamipes, a view maintained by Cabrera (1961). Gardner and Patton (1976) intimated the mixed composition of squamipes; Reig (in Honacki et al., 1982; 1986) has offered enumerations of valid species and probable synonymies. Fullscale generic revision warranted. See Ernest (1986, Mammalian Species, 265).