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.
Oxymycterus is a genus of rat-like rodents commonly known as hocicudos. They are endemic to South America. As of April 2019, the genus contains the following 16 species:
Euryoryzomys emmonsae, also known as Emmons' rice rat or Emmons' oryzomys, is a rodent from the Amazon rainforest of Brazil in the genus Euryoryzomys of the family Cricetidae. Initially misidentified as E. macconnelli or E. nitidus, it was formally described in 1998. A rainforest species, it may be scansorial, climbing but also spending time on the ground. It lives only in a limited area south of the Amazon River in the state of Pará, a distribution that is apparently unique among the muroid rodents of the region.
Euryoryzomys nitidus, also known as the elegant oryzomys or elegant rice rat, is a rodent species in the family Cricetidae. Previously it was known as Oryzomys nitidus, but it is not closely related to Oryzomys as that genus is now constructed. Its range includes Bolivia, Brazil and Peru to the east of the Andes, in lowland tropical rainforest as well as forest in the eastern foothills of the mountains, at elevations from 50 to 2,000 m.
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.
Neacomys minutus, also known as the minute neacomys, the small bristly mouse, or the minute spiny mouse, is a rodent species from South America in the genus Neacomys. It is found in Brazil.
Neacomys spinosus, also known as the common neacomys, common bristly mouse, or bristly mouse, is a nocturnal rodent species from South America in the genus Neacomys. It is found in Bolivia, Brazil, Colombia, Ecuador and Peru, where it often lives in transition areas between lowland forest and open regions. Its diet consists of insects, seeds and fruit.
The Caparaó hocicudo is a rodent species from South America. It is endemic to Brazil where it is found in the Pico da Bandeira mountain range.
Gardner's climbing mouse is a rodent species from South America. It is found in western Brazil, southeastern Peru and northeastern Bolivia. It is an uncommon, arboreal species, but faces no particular threats so the International Union for Conservation of Nature has rated it as being a "least-concern species".
The white-footed climbing mouse is a species of South American rodent found in Bolivia, Brazil, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela. It is the type species of the genus and the type location was the lower eastern slopes of the Andes in central Peru.
Scolomys ucayalensis, also known as the long-nosed scolomys or Ucayali spiny mouse is a nocturnal rodent species from South America. It is part of the genus Scolomys within the tribe Oryzomyini. It is found in Brazil, Colombia, Ecuador and Peru in various different habitats in the Amazon rainforest.
Proechimys is a genus of South American spiny rats of the family Echimyidae. All species of the genus are terrestrial. In the lowland Neotropical forests, Proechimys rodents are often the most abundant non-volant mammals. They are recognizable by reason of their elongated heads and long rostra, large and erect ears, narrow and long hind feet, and tails always shorter than head-and-body lengths. The dorsal pelage comprises a mixture of expanded, varyingly stiffened spines — hence the vernacular name of spiny rats — and soft hairs.
The Colombian forest mouse is a species of rodent in the family Cricetidae. Some authorities consider it to be the only species in the genus Chilomys, while others accept Chilomys fumeus as being a valid species, and it may form part of a species complex. It is found in Colombia, Ecuador, and Venezuela.
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 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.
Oxymycterus hucucha, also known as the Quechuan hocicudo, is a species of rodent in the genus Oxymycterus of family Cricetidae from South America. It is found only in a small region of the Andes in central Bolivia, where it lives in cloud forest at altitudes from 2600 to 3000 m.
The southern climbing mouse is a species of rodent in the family Cricetidae. It is found in Argentina and Bolivia in forested valleys and on slopes on the eastern side of the Andes Mountains.
Scolomys is a genus of rodent in the tribe Oryzomyini of the family Cricetidae. Some evidence suggests that it is related to Zygodontomys. It is characterized, among other traits, by spiny fur. It contains two species, S. melanops and S. ucayalensis.
The golden Oldfield mouse or golden thomasomys is a species of rodent in the family Cricetidae. It is found in Colombia, Ecuador, Peru, and Venezuela. Both the common and genus name commemorate the British zoologist Oldfield Thomas who worked at the Natural History Museum, London and studied South American rodents.
The Amazonian antshrike is a species of bird in the family Thamnophilidae, the antbirds. It occurs in the Amazon Basin of Brazil, and east to Maranhão state; also Amazonian Colombia, Ecuador, Peru, and Bolivia. It is in the Guianas in Guyana, Suriname and French Guiana, also two regions of Venezuela. Its natural habitats are subtropical or tropical moist lowland forests and subtropical or tropical swamps.
