Nephelomys nimbosus

{{Short description|Species of rodent}}

{{speciesbox

|genus=Nephelomys

|species=nimbosus

|authority=(Anthony, 1926)

|synonyms=Oryzomys auriventer nimbosus Anthony, 1926

[Nephelomys] nimbosus: Weksler, Percequillo, and Voss, 2006}}

Nephelomys nimbosus is a species of rodent in the genus Nephelomys of family Cricetidae.Weksler et al., 2006, p. 18 Its type locality is at San Antonio on the northeastern slope of the Tungurahua in the Andes of Ecuador, at an altitude of about {{convert|6700|ft|m|-2}}. The type series included five individuals.Anthony, 1926, p. 4

The fur of the upperparts is brown to blackish, becoming lighter towards the sides. The underparts are grayish, with a white patch at the throat. The long tail virtually lacks hairs and is darker above than below. In the holotype, the total length is {{convert|304|mm|in|2}}, the head and body length is {{convert|140|mm|in|2}}, the combined length of the tail vertebrae is {{convert|164|mm|in|2}}, the hindfoot length (including claws) is {{convert|34|mm|in|2}}, and the length of the skull is {{convert|35.5|mm|in|2}}. In most species of Nephelomys, the posterolateral palatal pits, perforations of the palate near the third molar, are conspicuous and receded into a depression or fossa, but in N. nimbosus and N. caracolus, they are much smaller.Weksler et al., 2006, p. 19

It was first described, in 1926, by American zoologist H. E. Anthony as a subspecies of Oryzomys auriventer. It is smaller than that animal and differs in coloration and in the shape of the incisive foramina, which resembles that seen in N. moerex.Anthony, 1926, p. 5 In his description, Anthony anticipated that O. auriventer would eventually be demoted to a subspecies of Oryzomys albigularis, which was indeed done in the early 1960s. Subsequently, O. auriventer was reinstated as a species separate from, though related to, O. albigularis, and nimbosus was considered to belong to the same species.Musser and Carleton, 2005, p. 1145 When the members of the Oryzomys albigularis group, including O. auriventer, were transferred to the new genus Nephelomys in 2006, N. nimbosus was recognized as a separate species.