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.
Cerradomys marinhus, also known as Marinho's rice rat, is a rodent species from South America. It is found in Minas Gerais, Brazil. It was formerly known as Oryzomys marinhus, but was transferred to the new genus Cerradomys in 2006.
Cerradomys subflavus, also known as the terraced rice rat or flavescent oryzomys, is a rodent species from South America in the genus Cerradomys. It is found in the states of Goiás, São Paulo, and Minas Gerais, Brazil. Populations in Bolivia, Paraguay, and elsewhere in Brazil that were previously placed in this species are now classified as various other species of Cerradomys.
Hylaeamys yunganus, also known as the Amazonian oryzomys or Yungas rice rat, is a species of rodent in the genus Hylaeamys of family Cricetidae. It is found in lowland tropical rainforest throughout Amazonia, in northeastern Bolivia, eastern Peru, eastern Ecuador, southeastern Colombia, southern Venezuela, Guyana, Suriname, French Guiana, and northern Brazil. A closely related species, Hylaeamys tatei, occurs only in a small area in eastern Ecuador. Both were previously placed in Oryzomys.
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.
Nephelomys albigularis, also known as the white-throated oryzomys or Tomes's rice rat, is a species of rodent in the genus Nephelomys of family Cricetidae. Described in 1860, it was the first Nephelomys species to be discovered. It was originally described in the defunct genus Hesperomys as Hesperomys albigularis and considered related to the much smaller H. longicaudatus. By 1894, it was placed in Oryzomys, as Oryzomys albigularis, and associated with what is now Nephelomys meridensis. In the early 1960s, the scope of the species was considerably expanded to include most of the species that are now in Nephelomys, as well as a single name, boliviae, that is currently a synonym of Euryoryzomys nitidus. From 1976 on, several of these were reinstated as separate species.
Handleyomys alfaroi, also known as Alfaro's rice rat or Alfaro's oryzomys, is a species of rodent in the genus Handleyomys of family Cricetidae. It is found in Belize, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. It was previously included in Oryzomys as Oryzomys alfaroi. Its natural habitats are subtropical and tropical lowland or montane dry forests at elevations ranging from sea level to 2500 m.
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.
Handleyomys chapmani, also known as Chapman's oryzomys or Chapman's rice rat, is a species of rodent in the genus Handleyomys of family Cricetidae. It is found only in Mexico. It was previously placed in Oryzomys as Oryzomys chapmani, but has been provisionally transferred to the genus Handleyomys pending the description of a new genus to contain it.
Handleyomys rhabdops, also known as the highland oryzomys or striped rice rat, is a species of rodent in the genus Handleyomys of family Cricetidae. It is nocturnal and is found in Guatemala and Mexico in montane forest at elevations from 1250 to 3250 m.
Handleyomys saturatior, also known as the cloud forest oryzomys or cloud forest rice rat, is a species of rodent in the genus Handleyomys of family Cricetidae. It is found in Belize, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua in cloud forest at elevations from 750 to 2500 m. It was previously placed in the genus Oryzomys.
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.
Cerradomys is a genus of oryzomyine rodents from eastern Bolivia, Paraguay, and central Brazil found in cerrado, Caatinga and Gran Chaco habitats.
Cerradomys maracajuensis, also known as the Maracaju oryzomys, is a rodent species from South America. It is terrestrial and is found in gallery forests in Bolivia, Paraguay and nearby Brazil and Peru. It was first discovered near the Brazilian city of Maracaju.
Cerradomys scotti, also known as Lindbergh's oryzomys, is a rodent species from South America in the genus Cerradomys. It is terrestrial and is found in the cerrado (savanna) ecozone of south central Brazil, Bolivia and Paraguay. The species is common and appears to tolerate a degree of agricultural habitat modification.
Hylaeamys is a genus of South American oryzomyine rodents found principally in humid forested areas east of the Andes. The species in this genus have historically been placed in Oryzomys. They are most closely related to Euryoryzomys, Transandinomys, Nephelomys, Oecomys, and Handleyomys, and most closely resemble species of the former two genera. They are distinguished from members of Euryoryzomys by all-dark or indistinct two-tone tail coloration, from members of Transandinomys by having shorter whiskers above their eyes that do not extend posteriorly behind their ears, and in both cases by differences in carotid circulation. The genus is named after hylaea, the term used by Humboldt for the lowland South American rainforests that are the main habitat of the genus.
Euryoryzomys is a genus of rodents in the tribe Oryzomyini of family Cricetidae. It includes seven species, which are distributed in South America. Until 2006, its members were included in the genus Oryzomys, but they are not closely related to the type species of that genus, and therefore they were placed in a new genus. They are most closely related to genera like Hylaeamys and Transandinomys; many members of these genera were previously placed in a single species, known as Oryzomys capito. The genus name, Euryoryzomys, combines the name "Oryzomys" with the Ancient Greek word eurus "broad", referring to the broad range in distribution of the genus.
Handleyomys is a genus of Central and South American rodents in the tribe Oryzomyini of family Cricetidae. It was first described in 2002 to include two species from the Colombian Andes which were previously included in distinct and unrelated genera, Aepeomys and Oryzomys, but which turned out to be closely related. Later, in 2006, six other species were provisionally added from Oryzomys; these are expected to be placed in new genera in the future.
Oryzomys peninsulae, also known as the Lower California rice rat, is a species of rodent from western Mexico. Restricted to the southern tip of the Baja California peninsula, it is a member of the genus Oryzomys of family Cricetidae. Only about twenty individuals, collected around 1900, are known, and subsequent destruction of its riverine habitat may have driven the species to extinction.
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.
