Rhagomys is a genus of South American rodents in the tribe Thomasomyini of the family Cricetidae.[1] Two species separated by about 3100 km[2] are known, from southeast Peru and Bolivia east of the Andes, and in the Atlantic Forest of southeast Brazil.[1] An undetermined species of Rhagomys has also been reported from Mato Grosso in central Brazil.[3] The species are as follows:

Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Cricetidae
Subfamily: Sigmodontinae
Tribe: Thomasomyini
Genus: Rhagomys
Thomas, 1917
Type species
Hesperomys rufescens
Thomas, 1886

Rhagomys longilingua
Rhagomys rufescens

This genus is distinguished from other sigmodontine rodents by the presence of a nail on the hallux.[2] Nuclear DNA sequence analysis has indicated that it is a sister taxon to Thomasomys.[2]

The geographic distribution may reflect a formerly continuous distribution made disjunct by extinctions, or may reflect limited sampling of the intervening areas.[4] While no other mammal taxa have a similar geographic distribution, a group of hylid frogs does.[4] Juscelinomys is an example of another sigmodontine rodent genus that also has a disjunct distribution.[4] Some disjunct distributions have been attributed to fluctuations in forest coverage during the Pleistocene, resulting from the climatic swings of the ice age.[4] However, the report of molars of an unknown member of the genus in an ocelot scat sample from a geographically intermediate location suggests that the disjunct distribution may well be artifact of limited sampling.[3]


  1. ^ a b Musser, G.G.; Carleton, M.D. (2005). "Superfamily Muroidea". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 1166. ISBN 978-0-8018-8221-0. OCLC 62265494.
  2. ^ a b c D'Elía, G.; Luna, L.; González, E. M.; Patterson, B. D. (February 2006). "On the Sigmodontinae radiation (Rodentia, Cricetidae): An appraisal of the phylogenetic position of Rhagomys". Molecular Phylogenetics and Evolution. Elsevier. 38 (2): 558–564. doi:10.1016/j.ympev.2005.08.011. PMID 16213166.
  3. ^ a b Percequillo, A. R.; Tirelli, F. P.; Michalski, F.; Eizirik, E. (2011). "The genus Rhagomys (Thomas 1917) (Rodentia, Cricetidae, Sigmodontinae) in South America: morphological considerations, geographic distribution and zoogeographic comments" (PDF). Mammalia. de Gruyter. 75: 195–199. doi:10.1515/MAMM.2011.007. Retrieved 2011-12-26.
  4. ^ a b c d Luna, L.; Patterson, B. D. (2003-04-30). "A Remarkable New Mouse (Muridae: Sigmodontinae) from Southeastern Peru: With Comments on the Affinities of Rhagomys rufescens (Thomas, 1886)" (PDF). Fieldiana Zoology. 101: 1–24. Retrieved 2011-12-26.