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 auyantepui, also known as the Guianan oecomys and north Amazonian arboreal rice rat, is a species of rodent in the genus Oecomys from South America. It is found in Guyana, Suriname, French Guiana, and nearby regions of Venezuela and Brazil. It is an arboreal rodent known from the understory of primary rainforest, found at altitudes from sea level to 1100 m.
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 northeastern Peru as well as central Brazil south of the Amazon, where it lives in lowland tropical rainforests.
Oligoryzomys chacoensis, also known as the Chacoan colilargo or Chacoan pygmy rice rat, is a rodent species from South America. It is found in the Gran Chaco region of southeastern Bolivia, southwestern Brazil, Paraguay, and northeastern Argentina. Its karyotype has 2n = 58 and FNa = 74.
Oligoryzomys flavescens, also known as the flavescent colilargo or yellow pygmy rice rat is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found in southern South America, occurring in southern Brazil, Paraguay, Uruguay, and northeastern Argentina. Its karyotype has 2n = 64-66 and FNa = 66–70.
Oligoryzomys microtis, also known as the small-eared colilargo or small-eared pygmy rice rat, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found in western Brazil, eastern Peru, Bolivia, and northern Paraguay.
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.
Oligoryzomys is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos. The genus is found from Mexico to Tierra del Fuego and includes approximately 17 species.
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.
Oligoryzomys andinus, also known as the Andean colilargo or Andean pygmy rice rat, is a species of rodent in genus Oligoryzomys of family Cricetidae. It is found in the Andes of southern Peru and western Bolivia, but may in fact include more than one species. Its karyotype has 2n = 60 and FNa = 70.
Oligoryzomys arenalis, also known as the sandy colilargo or sandy pygmy rice rat, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found in the Andes of Peru at 400 to 2850 m altitude, but may include more than one species.
Oligoryzomys destructor, also known as Tschudi's colilargo or the destructive pygmy rice rat, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found along the eastern Andes from southern Colombia, through Ecuador, Peru, and Bolivia into northern Argentina. Its karyotype has 2n = 60 and FNa = 76.
Oligoryzomys griseolus, also known as the grizzled colilargo or the grayish pygmy rice rat, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found in the Andes of Venezuela and nearby Colombia. Its karyotype has 2n = 62 and FNa = 74–76.
Oligoryzomys longicaudatus, also known as the long-tailed colilargo or long-tailed pygmy rice rat, is a species of rodent in the genus Oligoryzomys of the family Cricetidae. It is found in the southern Andes of Chile and Argentina, with an outlying population in eastern Argentina. As a common species with a wide range and a stable population, the International Union for Conservation of Nature has rated this rodent as being of "least concern".
Oligoryzomys magellanicus, also known as the Patagonian colilargo and the Magellanic pygmy rice rat, is a species of rodent in the genus Oligoryzomys of the family Cricetidae. It is found in the southernmost parts of Argentina and Chile, including Tierra del Fuego and other outlying islands. Its karyotype has 2n = 54 and FNa = 66.
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.
Oligoryzomys fornesi, also known as Fornes' colilargo, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found from northeastern Brazil via Paraguay into northeastern Argentina. Its karyotype has 2n = 62 and FNa = 64.
Oligoryzomys moojeni is a species of rodent from South America in the genus Oligoryzomys of family Cricetidae. It is known only from central Brazil, where it is found in the cerrado and gallery forests. It is named after twentieth-century Brazilian zoologist João Moojen. Its karyotype has 2n = 70 and FNa = 84.
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.
