The New World rats and mice are a group of related rodents found in

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north ...

and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

. They are extremely diverse in appearance and ecology, ranging in from the tiny ''

Baiomys ''Baiomys'' is the genus of New World pygmy mice. Together with '' Scotinomys'', it forms the tribe Baiomyini. It currently contains two extant species: *Southern pygmy mouse, '' Baiomys musculus'' *Northern pygmy mouse, '' Baiomys taylori'' ...

'' to the large ''

Kunsia The woolly giant rat (''Kunsia tomentosus'') is a species of large burrowing rodent native to South America. No subspecies are currently recognised. It is the only member of the genus ''Kunsia''. Description The woolly giant rat is an exceptio ...

''. They represent one of the few examples of

muroid rodent The Muroidea are a large superfamily of rodents, including mice, rats, voles, hamsters, lemmings, gerbils, and many other relatives. Although the Muroidea originated in Eurasia, they occupy a vast variety of habitats on every continent except A ...

s (along with the

voles Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...

) in North America, and the only example of muroid rodents to have made it into South America. The New World rats and mice are often considered part of a single subfamily,

Sigmodontinae 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 specie ...

, but the recent trend among muroid taxonomists is to recognize three separate subfamilies. This strategy better represents the extreme diversity of species numbers and ecological types. Some molecular phylogenetic studies have suggested that the New World rats and mice are not a

monophyletic group A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

, but this is yet to be confirmed. Their closest relatives are clearly the

hamster Hamsters are rodents (order Rodentia) belonging to the subfamily Cricetinae, which contains 19 species classified in seven genera.Fox, Sue. 2006. ''Hamsters''. T.F.H. Publications Inc. They have become established as popular small pets. The ...

s and

vole Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...

s. The New World rats and mice are divided into 3 subfamilies, 12 tribes, and 84 genera.

Classification

*Family

Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New World rats and mice. At almost 608 species, it is the second-largest family of mammals, and h ...

s, and New World rats and mice **Subfamily

Tylomyinae The subfamily Tylomyinae consists of several species of New World rats and mice including the vesper and climbing rats. They are not as well known as their relatives in the subfamilies Sigmodontinae and Neotominae. Many authorities place all t ...

***''

Otonyctomys Hatt's vesper rat (''Otonyctomys hatti''), also known as Hatt's vesper mouse or Yucatán vesper rat, is a species of rodent in the family Cricetidae. It is the only species in the genus ''Otonyctomys''. It is named for its discoverer, Robert T. ...

'' ***''

Nyctomys Sumichrast's vesper rat (''Nyctomys sumichrasti'') is a rodent of the family Cricetidae found from southern Mexico to Panama. It is named for the collector of the first specimen, and its closest relative is probably Hatt's vesper rat, a similar, ...

'' ***''

Tylomys ''Tylomys'' is a genus of rodent in the family Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New World rats and mice. At almost 6 ...

'' ***''

Ototylomys The big-eared climbing rat (''Ototylomys phyllotis'') is a species of rodent in the family Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrat ...

'' **Subfamily

Neotominae The Neotominae are a subfamily of the family Cricetidae. They consist of four tribes, 16 genera, and many species of New World rats and mice, predominantly found in North America. Among them are the well-known deer mice, white-footed mice, packr ...

***Tribe

Baiomyini Baiomyini is a tribe of rodents in the subfamily Neotominae occurring from the southern United States to Panama. It includes the genera ''Baiomys ''Baiomys'' is the genus of New World pygmy mice. Together with '' Scotinomys'', it forms the t ...

****''

'' ****''

Scotinomys ''Scotinomys'' is a genus of rodent, the singing mice, in the family Cricetidae. Together with ''Baiomys'', it forms the tribe Baiomyini Baiomyini is a tribe of rodents in the subfamily Neotominae occurring from the southern United States to P ...

'' ***Tribe Neotomini ****''

Neotoma A pack rat or packrat, also called a woodrat or trade rat, are any species in the North and Central American rodent genus ''Neotoma''. Pack rats have a rat-like appearance, with long tails, large ears, and large, black eyes. Pack rats are notice ...

'' ****'' Xenomys'' ****'' Hodomys'' ****'' Nelsonia'' ***Tribe Ochrotomyini ****'' Ochrotomys'' ***Tribe Reithrodontomyini ****''

Peromyscus ''Peromyscus'' is a genus of rodents. They are commonly referred to as deer mice or deermice, not to be confused with the chevrotain or "mouse deer". They are New World mice only distantly related to the common house and laboratory mouse, ''Mu ...

'' ****''

Reithrodontomys ''Reithrodontomys'' is the genus of groove-toothed New World harvest mice. Species This genus contains these species: * Baker's small-toothed harvest mouse, ''Reithrodontomys bakeri'' * Short-nosed harvest mouse, ''Reithrodontomys brevirostris'' ...

'' ****'' Onychomys'' ****'' Neotomodon'' ****'' Podomys'' ****''

Isthmomys ''Isthmomys'' is a genus of rodent in the family Cricetidae, belonging to the tribe Reithrodontomyini. Species are: *Yellow isthmus rat The yellow isthmus rat (''Isthmomys flavidus'') is a species of rodent in the family Cricetidae. It is fo ...

'' ****'' Megadontomys'' ****'' Habromys'' ****'' Osgoodomys'' **Subfamily

***'' Rhagomys'' ''

incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertain ...

'' ***Tribe

Oryzomyini Oryzomyini is a tribe of rodents in the subfamily Sigmodontinae of the family Cricetidae. It includes about 120 species in about thirty genera,Weksler et al., 2006, table 1 distributed from the eastern United States to the southernmost parts of ...

****''

Oryzomys ''Oryzomys'' is a genus of semiaquatic rodents in the tribe Oryzomyini living in southern North America and far northern South America. It includes eight species, two of which—the marsh rice rat (''O. palustris'') of the United States and ...

'' ****'' Nesoryzomys'' ****'' Melanomys'' ****'' Sigmodontomys'' ****''

Nectomys ''Nectomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae. Musser and Carleton, 2005. It is closely related to '' Amphinectomys'' and was formerly considered congeneric with ''Sigmodontomys''. It consists of five species, whic ...

'' ****''

Amphinectomys ''Amphinectomys savamis'', also known as the Ucayali water ratMusser and Carleton, 2005 or amphibious rat,Duff and Lawson, 2004 is a rodent from the Peruvian Amazon. It is placed as the only member of genus ''Amphinectomys'' in the tribe Oryzomyin ...

'' ****''

Oligoryzomys ''Oligoryzomys'' is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos.Musser and Carleton, 2005 The genus is found from Mexico to Tierra del Fuego and includes approximately 1 ...

'' ****''

Neacomys The genus ''Neacomys'', also known as bristly mice because of their spiny fur, includes several species of rodents in the tribe Oryzomyini of family Cricetidae. It is most closely related to ''Oligoryzomys'', ''Oreoryzomys'', and ''Microryzomys'' ...

'' ****''

Zygodontomys ''Zygodontomys'' is a genus of rodent in the tribe Oryzomyini of the family Cricetidae. Its closest relative may be '' Scolomys''. It ranges from Central America Central America ( es, América Central or ) is a subregion of the Americas ...

'' ****'' Lundomys'' ****''

Holochilus ''Holochilus'' is a genus of semiaquatic rodents in the tribe Oryzomyini of family Cricetidae,* sometimes called marsh rats. It contains five living species, '' H. brasiliensis'', '' H. chacarius'', '' H. nanus'', '' H. oxe'', and '' H. sciureus' ...

'' ****''

Pseudoryzomys ''Pseudoryzomys simplex'', also known as the Brazilian false rice rat or false oryzomys, is a species of rodent in the family Cricetidae from south-central South America. It is found in lowland palm savanna and thorn scrub habitats. It is a me ...

'' ****'' Microakodontomys'' ****''

Oecomys ''Oecomys'' is a genus of rodent within the tribe Oryzomyini of family Cricetidae. It contains about 17 species, which live in trees and are distributed across forested parts of South America, extending into Panama and Trinidad Trinidad i ...

'' ****''

Microryzomys ''Microryzomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae. It is closely related to '' Oreoryzomys'', '' Oligoryzomys'', and ''Neacomys''.Weksler, 2006 It contains two species, both restricted to the Andes: '' M. altissim ...

'' ****'' Scolomys'' ***Tribe Thomasomyini ****'' Chilomys'' ****'' Abrawayaomys'' ****''

Delomys ''Delomys'' is a genus of South American rodents in the tribe Thomasomyini of family Cricetidae. Four species are known, all found in the Atlantic Forest of Argentina and Brazil. They are as follows: * '' Delomys altimontanus'' * Montane Atla ...

'' ****''

Thomasomys ''Thomasomys'' is a genus of rodent in the family Cricetidae, named after British zoologist Oldfield Thomas. Nuclear DNA sequence analysis has indicated that it is a sister taxon to '' Rhagomys''. It contains the following species: * Anderson' ...

'' ****'' Wilfredomys'' ****'' Aepomys'' ****'' Phaenomys'' ****''

Rhipidomys ''Rhipidomys'' is a genus of rodents in the family Cricetidae, The following 24 species of climbing mouse species are currently recognised: * '' Rhipidomys albujai'' * Southern climbing mouse (''Rhipidomys austrinus'') * Cariri climbing mouse ( ...

'' ***Tribe Wiedomyini ****'' Wiedomys'' ***Tribe Akodontini ****''

Akodon ''Akodon'' is a genus consisting of South American grass mice. They mostly occur south of the Amazon Basin and along the Andes north to Venezuela, but are absent from much of the basin itself, the far south of the continent, and the lowlands west ...

'' ****''

Bibimys ''Bibimys'' is a genus of new world rats. Commonly known as the crimson-nosed rats, there are three species: *'' Bibimys chacoensis'' - Chaco crimson-nosed rat - found in north-east Argentina and Paraguay *'' Bibimys labiosus'' - Large-lipped c ...

'' ****'' Bolomys'' ****''

Podoxymys The Roraima mouse (''Podoxymys roraimae'') is a species of rodent in the family Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New ...

'' ****''

Thalpomys ''Thalpomys'' is a genus of South American rodents in the tribe Akodontini of family Cricetidae. Two species are known, both found in the cerrado tropical savanna ecoregion of central Brazil Brazil ( pt, Brasil; ), officially the Federati ...

'' ****''

Abrothrix ''Abrothrix'' is a genus of rodent in the tribe Abrotrichini of family Cricetidae. It contains the following living species:Teta et al., 2017 *''Abrothrix andina'' *''Abrothrix hershkovitzi'' *''Abrothrix hirta'' *''Abrothrix illutea'' *''Abrothri ...

'' ****'' Chroeomys'' ****''

Chelemys ''Chelemys'' is a genus of South American rodents in the tribe Abrotrichini of family Cricetidae. Three species—'' Chelemys delfini'', '' Chelemys macronyx'', and '' Chelemys megalonyx''—are known, all found in central and southern Chile and A ...

'' ****''

Notiomys ''Notiomys edwardsii'', also known as Edwards's long-clawed mouse, Edward's long-clawed akodont,Musser and Carleton, 2005, p. 1136 or Milne-Edwards' long-clawed mouse, is a rodent in the tribe Abrotrichini from southern Argentina. It is the ...

'' ****'' Pearsonomys'' ****''

Geoxus ''Geoxus'' is a genus of South American rodents in the tribe Abrotrichini of family Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and ...

'' ****'' Blarinomys'' ****''

Juscelinomys ''Juscelinomys'' is a genus of burrowing mice. The name is derived from Brazilian president Juscelino Kubitschek Juscelino Kubitschek de Oliveira (; 12 September 1902 – 22 August 1976), also known by his initials JK, was a prominent Bra ...

'' ****''

Oxymycterus ''Oxymycterus'' is a genus of rat-like rodents commonly known as hocicudos. They are endemic to South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively sma ...

'' ****'' Lenoxus'' ****''

Brucepattersonius ''Brucepattersonius'' is a genus of rodents within the tribe Akodontini from southeastern South America. Also known as brucies, the genus is named after Bruce Patterson, MacArthur Curator at the Department of Zoology (Mammals), at the Field Mu ...

'' ****''

Scapteromys ''Scapteromys'' is a genus of South American rodents in the tribe Akodontini of family Cricetidae. Three species are known, found in northern Argentina, southern Brazil, Paraguay and Uruguay. They are as follows: * Argentine swamp rat (''Scapte ...

'' ****''

'' ***Tribe Phyllotini ****'' Calomys'' ****'' Eligmodontia'' ****'' Andalgalomys'' ****''

Graomys ''Graomys'' is a genus of rodent in the family Cricetidae. It contains the following species: * Central leaf-eared mouse (''Graomys chacoensis'') * Pale leaf-eared mouse The pale leaf-eared mouse (''Graomys domorum'') is a species of rodent i ...

'' ****'' Salinomys'' ****'' Phyllotis'' ****'' Loxodontomys'' ****'' Auliscomys'' ****'' Galenomys'' ****'' Chinchillula'' ****''

Punomys ''Punomys'' is a genus of rodent in the family Cricetidae The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New World rats and mice. At almost 6 ...

'' ****'' Andinomys'' ****''

Irenomys ''Irenomys tarsalis'', also known as the Chilean climbing mouse, Chilean tree mouse, or long-footed irenomys,Musser and Carleton, 2005, p. 1121 is a rodent found in Chile, from about 36° to 46°S, and in adjacent Argentina, mainly in forests. It ...

'' ****''

Euneomys ''Euneomys'' is a genus of rodent in the family Cricetidae. It contains the following species: * Patagonian chinchilla mouse (''Euneomys chinchilloides'') * Burrowing chinchilla mouse The burrowing chinchilla mouse (''Euneomys fossor'') is a sp ...

'' ****'' Neotomys'' ****''

Reithrodon ''Reithrodon'' is a genus of rodent in the family Cricetidae. It contains the following living species: * Bunny rat (''Reithrodon auritus'') * Naked-soled conyrat (''Reithrodon typicus'') The scientific name translates as "channel tooth" and r ...

'' ***Tribe Sigmodontini ****'' Sigmodon'' ***Tribe Ichthyomyini ****''

Neusticomys ''Neusticomys'' is a genus of semiaquatic, animalivorous South American rodents in the family Cricetidae. The term ''Neusticomys'' derives from the two ancient greek Ancient Greek includes the forms of the Greek language used in ancien ...

'' ****''

Rheomys ''Rheomys'' is a genus of Mexican and Central American semiaquatic rodents in the family Cricetidae. It contains the following species: * Mexican water mouse, ''Rheomys mexicanus'' * Goldman's water mouse, ''Rheomys raptor'' * Thomas's water mou ...

'' ****'' Anotomys'' ****'' Chibchanomys'' ****''

Ichthyomys ''Ichthyomys'' is a genus of semiaquatic Neotropical rodents in the family Cricetidae. It contains the following species: * Crab-eating rat (''Ichthyomys hydrobates'') * Pittier's crab-eating rat (''I. pittieri'') * Stolzmann's crab-eating rat ...

References

*Centers for Disease Control, 2002.
"Hantavirus Pulmonary Syndrome — United States: Updated Recommendations for Risk Reduction."
''Mortality and Morbidity Weekly Report'', 51:09. Retrieved on 2007-07-13. *D'Elia, G. 2003. Phylogenetics of Sigmodontinae (Rodentia, Muroidea, Cricetidae), with special reference to the akodont group, and with additional comments on historical biogeography. Cladistics 19:307-323. *Mares, M. A., and J. K. Braun. 2000.

, the genus that ate South America: A reply to Steppan and Sullivan. Journal of Mammalogy 81:271-276. *McKenna, M. C. and S. K. Bell. 1997. Classification of Mammals above the

Species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

Level. Columbia University Press, New York. *Steppan, S. J., R. A. Adkins, and J. Anderson. 2004.

Phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spe ...

and divergence date estimates of rapid radiations in

muroid The Muroidea are a large superfamily of rodents, including mice, rats, voles, hamsters, lemmings, gerbils, and many other relatives. Although the Muroidea originated in Eurasia, they occupy a vast variety of habitats on every continent excep ...

rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...

s based on multiple nuclear genes. Systematic Biology, 53:533-553. {{DEFAULTSORT:New World Rats And Mice Cricetidae Paraphyletic groups