Nephelomys pirrensis
Encyclopedia
Nephelomys pirrensis, also known as the Mount Pirre Rice Rat, is a species of rodent
in the genus Nephelomys
of family Cricetidae
. Its type locality is at Mount Pirri or Pirre in eastern Panama
, at an altitude of 4500 feet (1,371.6 m), 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. Juveniles have darker fur. It is similar in size to N. devius, which occurs further west in Costa Rica
, but is somewhat darker and has smaller auditory bulla
e. In six specimens, the total length ranges from 309 to 340 mm (12.2 to 13.4 in), the length of the tail vertebrae from 159 to 185 mm (6.3 to 7.3 in), and the hindfoot length from 34 to 38 mm (1.3 to 1.5 in).
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, which is similar in appearance, but has longer ears and a hairier tail.
It was first described, in 1913, as a species
of Oryzomys
, Oryzomys pirrensis, but later synonymized
under Oryzomys albigularis (currently Nephelomys albigularis). When that species was transferred to the new genus Nephelomys
in 2006, N. nimbosus was recognized as a separate species.
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
in the genus Nephelomys
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...
of family Cricetidae
Cricetidae
The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, and New World rats and mice...
. Its type locality is at Mount Pirri or Pirre in eastern Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...
, at an altitude of 4500 feet (1,371.6 m), 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. Juveniles have darker fur. It is similar in size to N. devius, which occurs further west in Costa Rica
Costa Rica
Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....
, but is somewhat darker and has smaller auditory bulla
Auditory bulla
The auditory bulla is a hollow bony structure on the ventral, posterior portion of the skull of placental mammals that encloses parts of the middle and inner ear. In most species, it is formed by the tympanic part of the temporal bone.In extant primates, the structure is found in tarsiers,...
e. In six specimens, the total length ranges from 309 to 340 mm (12.2 to 13.4 in), the length of the tail vertebrae from 159 to 185 mm (6.3 to 7.3 in), and the hindfoot length from 34 to 38 mm (1.3 to 1.5 in).
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, which is similar in appearance, but has longer ears and a hairier tail.
It was first described, in 1913, as a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of Oryzomys
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 of the United States and O. couesi of Mexico and Central America—are widespread; the six others have...
, Oryzomys pirrensis, but later synonymized
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
under Oryzomys albigularis (currently Nephelomys albigularis). When that species was transferred to the new genus Nephelomys
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...
in 2006, N. nimbosus was recognized as a separate species.
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. ISBN 978-0-8018-8221-0
- Weksler, M., A. R. Percequillo, and R.S. Voss. 2006. Ten new genera of oryzomyine rodents (Cricetidae: Sigmodontinae). American Museum Novitates 3537:1–29.