''Hylaeamys oniscus'', the sowbug rice rat, is a

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 lower jaws. About 40% of all mammal species are roden ...

species in the 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 almost 608 species, it is the second-largest family of mammals, a ...

. It was formerly placed in the genus ''

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 ...

'' as ''Oryzomys oniscus''. It occurs only in northeastern

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. It is close to ''

Hylaeamys laticeps ''Hylaeamys laticeps'', also known as the Atlantic Forest oryzomysMusser and Carleton, 2005 or the large-headed rice rat, is a species of rodent in the family Cricetidae. The rodent is endemic to the Atlantic Forest region of southeastern Bra ...

'', which occurs further south in Brazil, and the two have been considered to be the same species.

References

Hylaeamys Rodents of South America Mammals of Brazil Endemic fauna of Brazil Mammals described in 1904 Taxa named by Oldfield Thomas {{Sigmodontinae-stub