Nectomys rattus Pelzeln 1883

Wilson, Don E. & Reeder, DeeAnn, 2005, Order Rodentia - Family Cricetidae, Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2, Baltimore: The Johns Hopkins University Press, pp. 955-1189 : 1133

Nectomys rattus Pelzeln 1883

Nectomys rattus Pelzeln 1883 , Verhl. kaiserl.-konigl. zool.-bot. Gesellsch., Wien, 33 ((Suppl.)): 73.

Type Locality: Brazil, Amazonas State, right bank of upper Rio Negro, Marabitanas, 100 m.

Vernacular Names: Amazonian Nectomys.

Synonyms: Nectomys amazonicus Hershkovitz 1944 ; Nectomys mattensis Thomas 1903 ; Nectomys melanius Thomas 1910 ; Nectomys parvipes Petter 1979 ; Nectomys tarrensis Hershkovitz 1948 .

Distribution: Amazonia—E Colombia, NW and S Venezuela, Guianas, N and C Brazil, and perhaps lowlands of E Perú; distributional limits need specimen-based verification.

Conservation: IUCN – Critically Endangered as N. parvipes .

Discussion: Most forms included here were once treated as subspecies of N. squamipes following Hershkovitz (1944). Diagnosis emended as the species N. melanius and morphology contrasted to N. palmipes and N. squamipes sensu stricto by Voss et al. (2001); they mentioned that rattus Pelzeln (1883) may be the proper name to use for this species and provided information on the type’s existence and its identity as a Nectomys (2001:98-99, footnote). Bonvicino (in Andrades-Miranda et al., 2001 b) has employed the name rattus as senior synonym for populations with 2n = 52-54 (Baker et al., 1983; Barros et al., 1992; Voss et al., 2001), a usage acknowledged by Andrades-Miranda et al. (2001 b); whereas, Patton et al. (2000) suggested mattensis as the oldest name applicable to this widespread karyotypic variant. The provisional basis for the senior name, included synonyms, and geographic range cobbled together here is patently clear and must be confirmed by more robust studies that include topotypic material. Bonvicino (1999) reassigned Nectomys parvipes Petter (1979) as another species of Sigmodontomys , but Voss et al. (2001) considered the type to represent a small individual of melanius (here = N. rattus ); a third and final determination is required.