''Nephelomys pirrensis'', also known as the Mount Pirre rice rat,Goldman, 1920, p. 100 is a species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

in the genus ''

Nephelomys ''Nephelomys'' is a genus of South American oryzomyine rodents found in the Andes from Bolivia to Venezuela, with a westward extension into the mountains of Costa Rica. Its generic name is derived from the Ancient Greek word ''nephelê'' "mist", ...

'' of family

Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New World rats and mice. At over 870 species, it is either the largest or second-largest family ...

. Its type locality is at Mount Pirri or Pirre in eastern

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

, at an altitude of ,Goldman, 1913, p. 5 and it has also been recorded on Mount Tacarcuna. ''N. pirrensis'' is a relatively large species. The color of the upperparts is brown and becomes lighter towards the sides. The throat is gray and the other parts of the underparts are buffy. The nose, ears, and forefeet are blackish and the thinly haired hindfeet are dark brown. The tail is dark brown above and a little paler below.Goldman, 1913, p. 6 Juveniles have darker fur. It is similar in size to '' N. devius'', which occurs further west in

Costa Rica Costa Rica, officially the Republic of Costa Rica, is a country in Central America. It borders Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, and the Pacific Ocean to the southwest, as well as Maritime bo ...

, but is somewhat darker and has smaller

auditory bulla The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal. It originates as a separate bone (tympanic b ...

e. In six specimens, the total length ranges from , the length of the tail

vertebra Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spina ...

e from , and the hindfoot length from . It lives in holes under rocks and logs along streams. Several specimens were caught in animal runways. On Mount Tacarcuna, it occurs together with the much more common ''

Isthmomys pirrensis The Mount Pirri isthmus rat (''Isthmomys pirrensis'') is a species of rodent in the family Cricetidae. Its natural habitat is subtropical or tropical moist lowland forests. It is found only in Panama. At the time of its discovery, it was conside ...

'', which is similar in appearance, but has longer ears and a hairier tail. It was first described, in 1913, as a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of ''

Oryzomys ''Oryzomys'' is a genus of semiaquatic rodents in the tribe Oryzomyini living in southern North America and far northern South America. It includes eight species, two of which—the marsh rice rat (''O. palustris'') of the United States and ...

'', ''Oryzomys pirrensis'', but later synonymized under ''Oryzomys albigularis'' (currently ''

Nephelomys albigularis ''Nephelomys albigularis'', also known as the white-throated oryzomys or Tomes's rice rat, is a species of rodent in the genus '' Nephelomys'' of family Cricetidae. Described in 1860, it was the first ''Nephelomys'' species to be discovered. It w ...

''). When that species was transferred to the new genus ''

'' in 2006, ''N. nimbosus'' was recognized as a separate species.Weksler et al., 2006, p. 18

References

Literature cited

*Goldman, E.A. 1913. Descriptions of new mammals from Panama and Mexico. Smithsonian Miscellaneous Collections 60(22):1–20. *Goldman, E.A. 1918. The rice rats of North America. North American Fauna 43:1–100. *Goldman, E.A. 1920. The mammals of Panama. Smithsonian Miscellaneous Collections 69(5):1–309. *Musser, G.G. and Carleton, M.D. 2005. Superfamily Muroidea. Pp. 894–1531 in Wilson, D.E. and Reeder, D.M. (eds.). Mammal Species of the World: a taxonomic and geographic reference. 3rd ed. Baltimore: The Johns Hopkins University Press, 2 vols., 2142 pp. * {{Taxonbar, from=Q6995005 Rodents of Central America Nephelomys Mammals described in 1913 Taxa named by Edward Alphonso Goldman