The rodent subfamily Sigmodontinae includes New World rats and mice, with at least 376 species. Many authorities include the Neotominae and Tylomyinae as part of a larger definition of Sigmodontinae. When those genera are included, the species count numbers at least 508. Their distribution includes much of the New World, but the genera are predominantly South American, such as brucies. They invaded South America from Central America as part of the Great American Interchange near the end of the Miocene, about 5 million years ago. Sigmodontines proceeded to diversify explosively in the formerly isolated continent. They inhabit many of the same ecological niches that the Murinae occupy in the Old World.
Sooretamys angouya, also known as the rat-headed rice rat, and Paraguayan rice rat, is a rodent species from South America. It is found in northeastern Argentina, southern Brazil and Paraguay in forested areas within the Atlantic Forest and cerrado. Since 2006, it has been classified as the only species in the genus Sooretamys; previously, it was included in the genus Oryzomys. Its taxonomic history has been complex, with the names Oryzomys angouya, Oryzomys buccinatus, and Oryzomys ratticeps in use for various parts of the species at different times. Some variation in its karyotype has been reported, with 2n = 80 to 82 and FN = 88 to 90.
Oecomys paricola, also known as the Brazilian oecomys, Brazilian arboreal rice rat, or South Amazonian arboreal rice rat, is a species of rodent in the genus Oecomys of family Cricetidae. It is found in central Brazil south of the Amazon, where it lives in lowland tropical rainforest.
Oecomys trinitatis, also known as the long-furred oecomys, long-furred rice rat, Trinidad arboreal rice rat, or big arboreal rice rat, is a species of rodent in the genus Oecomys of family Cricetidae. As currently constituted, it has a wide distribution in Central America and South America, being found in southern Costa Rica, Panama, Colombia, Venezuela, Trinidad and Tobago, Guyana, Suriname, French Guiana, much of Brazil, eastern Ecuador, and eastern Peru.
Oligoryzomys fulvescens, also known as the fulvous colilargo, fulvous pygmy rice rat, or northern pygmy rice rat, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found from southern Mexico through Central America into South America, where it occurs south into Peru and Brazil, and includes numerous synonyms, including the type species of the genus, Oryzomys navus Bangs, 1899. The taxonomy of this species is unresolved, and it may be found to contain more than one species. Its karyotype has 2n = 54-60 and FNa = 68–74.
Oligoryzomys nigripes, also known as the black-footed colilargo or the black-footed pygmy rice rat, is a rodent in the genus Oligoryzomys of family Cricetidae. Oligoryzomys nigripes is a species that has been further divided into different sister taxa throughout history. It is found in different countries in South America. It is a large species with long ears, dark yellow to dark brown upperparts, sharply delimited from the whitish underparts, and often a pink girdle on the chest. This species of rat spends much of its life among the trees. The karyotype is 2n = 62, FNa = 78–82.
Oligoryzomys stramineus, also known as the straw-colored colilargo or straw-colored pygmy rice rat, is a species of rodent in the genus Oligoryzomys of the family Cricetidae. It occurs only in the cerrado and caatinga ecoregions of northeastern Brazil. Its karyotype has 2n = 52 and FNa = 68-70.
Water rat(s) may refer to:
Nectomys palmipes, also known as the Trinidad nectomys or Trinidad water rat, is a species of semiaquatic rodent in genus Nectomys of family Cricetidae. It is found on the island of Trinidad and on the nearby mainland of Venezuela.
Nectomys is a genus of rodent in the tribe Oryzomyini of family Cricetidae. It is closely related to Amphinectomys and was formerly considered congeneric with Sigmodontomys. It consists of five species, which are allopatrically distributed across much of South America: Nectomys grandis in montane Colombia; Nectomys palmipes on Trinidad and in nearby Venezuela, Nectomys apicalis in the western margins of the Amazon biome, Nectomys rattus in much of Amazonia, and Nectomys squamipes in the Atlantic Forest of Brazil. These species are generally semiaquatic, are normally found near water, and are commonly called water rats.
Nesoryzomys fernandinae, also known as the Fernandina nesoryzomys, Fernandina rice rat, or Fernandina Galápagos mouse, is a species of rodent in the genus Nesoryzomys of family Cricetidae. It is found only on Fernandina in the Galápagos Islands, which it shares with N. narboroughi. Its natural habitat is subtropical or tropical dry shrubland. The conservation status of this endemic species continues to be investigated.
Oecomys speciosus, also known as the savannah oecomys, arboreal rice rat, or Venezuelan arboreal rice rat, is a species of rodent in the genus Oecomys of family Cricetidae. It ranges over northeastern Colombia and much of Venezuela, including the island of Trinidad. This rodent lives in tropical rainforest and tropical dry forest, including secondary forest and gallery forest, as well as in savanna habitat.
Nephelomys devius, also known as the Talamancan oryzomys, Boquete rice rat, Chiriqui rice rat, or montane rice rat, is a species of rodent in the genus Nephelomys of family Cricetidae. It is found in cloud forest in the highlands of Costa Rica and western Panama.
Oryzomys dimidiatus, also known as the Nicaraguan oryzomys, Thomas's rice rat, or the Nicaraguan rice rat, is a rodent in the family Cricetidae. It is known from only three specimens, all collected in southeastern Nicaragua since 1904. Placed in Nectomys upon its discovery, it was later classified in its own subgenus of Oryzomys and finally recognized as closely related to other species now placed in Oryzomys, including the marsh rice rat and Coues' rice rat, which occurs in the same region.
Nephelomys keaysi, also known as Keays's oryzomys or Keays's rice rat, is a species of rodent in the genus Nephelomys of family Cricetidae. It is found from southeastern Peru to northern Bolivia on the eastern slope of the Andes in Yungas humid forest at altitudes of 1000 to 2600 m. Although its continued existence is not in serious danger and it is listed as "least concern", destruction of its habitat may pose a threat to some populations.
Sigmodontomys alfari, also known as the short-tailed sigmodontomys, Alfaro's rice water rat, Cana rice rat, or Allen's rice rat, is a species of rodent in the subfamily Sigmodontinae of family Cricetidae. It is found from Honduras through Nicaragua, Costa Rica, and Panama into South America, where it occurs from Venezuela through Colombia to Ecuador.
Tanyuromys aphrastus, known as the long-tailed sigmodontomys, Harris's rice water rat, or the long-tailed rice rat, is a species of rodent in the family Cricetidae. It is known from Costa Rica, Panama, and Ecuador. In 2012, it was reassigned to its current genus from Sigmodontomys.
Oryzomyini is a tribe of rodents in the subfamily Sigmodontinae of the family Cricetidae. It includes about 120 species in about thirty genera, distributed from the eastern United States to the southernmost parts of South America, including many offshore islands. It is part of the clade Oryzomyalia, which includes most of the South American Sigmodontinae.
Nectomys apicalis, also known as the western Amazonian nectomys, is a semiaquatic species of rodent in the genus Nectomys of family Cricetidae. It is found east of the Andes in Ecuador, Peru, and Bolivia, east into western Brazil; further to the east, it is replaced by N. rattus. It lives near watercourses in lowland tropical rainforest. Its karyotype has 2n = 38–42, and it probably actually represents several distinct undescribed species.
Euryoryzomys macconnelli, also known as MacConnell's rice rat or MacConnell's oryzomys, is a rodent species from South America. It is found in Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela, where it lives in lowland tropical rainforest. It was formerly placed in the genus Oryzomys, as Oryzomys macconnelli, but in 2006 it was reclassified as the type species of the new genus Euryoryzomys.
