The Muroidea are a large superfamily of rodents, including mice, rats, voles, hamsters, gerbils, and many other relatives. They occupy a vast variety of habitats on every continent except Antarctica. Some authorities have placed all members of this group into a single family, Muridae, due to difficulties in determining how the subfamilies are related to one another. The following taxonomy is based on recent well-supported molecular phylogenies.
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.
Oecomys concolor, also known as the unicolored oecomys, unicolored rice rat, or unicolored arboreal rice rat, is a species of rodent in the genus Oecomys of family Cricetidae. It is found in tropical rainforest in the Amazon biome, but its range is poorly documented; it has been recorded in northwestern Brazil, southeastern Colombia, and southern Venezuela.
Neacomys dubosti, also known as Dubost's neacomys or Dubost's bristly mouse, is a species of South American rodent in the genus Neacomys of family Cricetidae. It is found in French Guiana, southeastern Suriname and nearby Amapá, Brazil. It was not recognized as distinct from N. guianae until 2001.
Neacomys paracou, also known as the Paracou neacomys or Paracou bristly mouse, is a rodent species from South America in the genus Neacomys. It is found in northern Brazil, French Guiana, Guyana, Suriname and southeastern Venezuela.
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.
Neacomys tenuipes, also known as the narrow-footed neacomys or narrow-footed bristly mouse, is found along the northern Andes from northwestern Venezuela through Colombia into Ecuador, in rainforest at elevations from 400 to 1750 m. Populations of small Neacomys in the lowland Amazon basin, previously assigned to this species, are now recognized as belonging to separate species.
The transitional colilargo also known as the intermediate lesser grass mouse, is a species of rodent in the tribe Oryzomyini known only from two individuals found in the Federal District of Brazil. Although described as a link between oryzomyine and akodontine rodents and placed in its own genus, Microakodontomys, Weksler and coworkers dismissed it as an aberrant Oligoryzomys.
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.
Handleyomys fuscatus, also known as the dusky-footed Handley's mouse or dusky-footed montane mouse, is a species of rodent in the tribe Oryzomyini of family Cricetidae. It was previously placed in the genus Aepeomys, but it is closely similar to Handleyomys intectus, and accordingly both species were placed in the new genus Handleyomys in 2002. It is found only in Colombia.
Microryzomys is a genus of rodent in the tribe Oryzomyini of family Cricetidae. It is closely related to Oreoryzomys, Oligoryzomys, and Neacomys. It contains two species, both restricted to the Andes: M. altissimus and M. minutus.
Neacomys pictus, also known as the painted neacomys or painted bristly mouse, is a species of rodent in the genus Neacomys of family Cricetidae. It is found only in Panama.
Nectomys rattus, the small-footed bristly mouse, Amazonian nectomys, Amazonian mouse, or common water rat is a species of rodent in the genus Nectomys of family Cricetidae. It is found in Brazil, Colombia, French Guiana, Guyana, Suriname, and Venezuela, where it lives in a variety of habitats including lowland tropical rainforest, cerrado and caatinga. It is mainly found in areas close to water. It was recognized as distinct only in 2000 and its limits with other Nectomys, including Nectomys apicalis and Nectomys squamipes, remain unclear.
Oreoryzomys balneator, also known as the Peruvian rice rat or Ecuadoran oryzomys, is a species of rodent in the tribe Oryzomyini of family Cricetidae. It is found in Ecuador and northern Peru in cloud forest at elevations from 1500 to 1800 m. It is the only species in the genus Oreoryzomys, which was included in Oryzomys until 2006. The genus name Oreoryzomys is a combination of ορος the Greek word for "mountain" with the old genus name Oryzomys and refers to the mountainous habitat of O. balneator. Recent research suggests that O. balneator is not closely related to Oryzomys, but instead is probably related to Microryzomys within a clade also including Neacomys and Oligoryzomys.
Aegialomys xanthaeolus, also known as the yellowish oryzomys or yellowish rice rat, is a species of rodent in the family Cricetidae. It belongs to the genus Aegialomys in tribe Oryzomyini, which was not recognized as distinct from Oryzomys until 2006. It is found in coastal Ecuador and Peru. Though it is currently the only formally recognized mainland species of Aegialomys, at least one other exists. The specific name is sometimes incorrectly spelled "xantheolus", without the second "a".
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.
Sigmodontomys is a genus of rodent in the tribe Oryzomyini of family Cricetidae. It is related to Nectomys and Melanomys and used to be included in Nectomys. It includes two species, Sigmodontomys alfari and the much rarer Sigmodontomys aphrastus, but whether these are indeed each other's closest relatives is uncertain.
Oryzomyini is a tribe of rodents in the subfamily Sigmodontinae of 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.
In anatomy, posterolateral palatal pits are gaps at the sides of the back of the bony palate, near the last molars. Posterolateral palatal pits are present, in various degrees of development, in several members of the rodent family Cricetidae. Many members of the family lack them or have only simple pits, but Arvicolinae and Oryzomyini have more highly developed posterolateral palatal pits. Posterolateral palatal pits are also present in some other rodents, including Glis, Jaculus, Hystrix, Abrocoma, Ctenomys, Chinchilla, and Lagidium.
In mammals, ungual tufts are tufts of hairs at the base of claws of the forefeet and hindfeet. Their presence has been used as a character in cladistic studies of the Cricetidae, a large family of rodents.
