''Rattus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 except ...

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

s, all typically called rats. However, the term

rat Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include '' Neotoma'' (pack rats), '' Bandicota'' (bandicoo ...

can also be applied to rodent species outside of this genus.

Species and description

The best-known ''Rattus''

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

are the

black rat The black rat (''Rattus rattus''), also known as the roof rat, ship rat, or house rat, is a common long-tailed rodent of the stereotypical rat genus ''Rattus'', in the subfamily Murinae. It likely originated in the Indian subcontinent, but is n ...

(''R. rattus'') and the

brown rat The brown rat (''Rattus norvegicus''), also known as the common rat, street rat, sewer rat, wharf rat, Hanover rat, Norway rat and Norwegian rat, is a widespread species of common rat. One of the largest Muroidea, muroids, it is a brown or grey ...

(''R. norvegicus''). The group is generally known as the

Old World The "Old World" () is a term for Afro-Eurasia coined by Europeans after 1493, when they became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia in the Eastern Hemisphere, previously ...

rats or true rats and originated in

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. Rats are bigger than most Old World

mice A mouse (: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...

, which are their relatives, but seldom weigh over in the wild.

Taxonomy of ''Rattus''

The genus ''Rattus'' is a member of the giant subfamily

Murinae The Old World rats and mice, part of the subfamily Murinae in the family Muridae, comprise at least 519 species. Members of this subfamily are called murines. In terms of species richness, this subfamily is larger than all mammal families excep ...

. Several other murine genera are sometimes considered part of ''Rattus'': ''

Lenothrix The gray tree rat (''Lenothrix canus'') is a species of rodent in the family Muridae. monotypic taxon, only species in the genus ''Lenothrix''. It is found in forests in Indonesia and Malaysia. A common species, the International Union for Conse ...

'', ''

Anonymomys The Mindoro climbing rat or Mindoro rat (''Anonymomys mindorensis'') is a species of rodent in the family Muridae. It is found only in the Philippines, and is known only from Ilong Peak in the Halcon Mountains. It is the only species in the gen ...

'', ''

Sundamys ''Sundamys'' is a genus of rodent in the family Muridae, found mostly in Indonesia and Malaysia.Camacho-Sanchez, M., Jennifer A. Leonard, Yuli Fitriana, Marie-Ka Tilak, and Pierre-Henri Fabre. 2017. "The generic status of Rattus annandalei (Bonho ...

'', ''

Kadarsanomys Sody's tree rat (''Kadarsanomys sodyi'') is a rodent species in the family Muridae that has been recorded only in bamboo forest in Gunung Gede Pangrango National Park, West Java, Indonesia Indonesia, officially the Republic of Indonesia, ...

'', ''

Diplothrix ''Diplothrix'' is a genus of two species of rodents in the family Muridae. '' Diplothrix legata'' occurs in the Ryukyu Islands of Japan. '' Diplothrix yangziensis'' is known only from fossils collected in eastern China, dating to the Early Pleist ...

'', ''

Margaretamys ''Margaretamys'' is a genus of rodent in the family Muridae endemic to the island of Sulawesi in Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and P ...

'', ''

Lenomys ''Lenomys'' is a genus of rodent endemic to Sulawesi Sulawesi ( ), also known as Celebes ( ), is an island in Indonesia. One of the four Greater Sunda Islands, and the List of islands by area, world's 11th-largest island, it is situated eas ...

'', ''

Komodomys The Komodo rat (''Komodomys rintjanus'') is a species of rodent in the family Muridae endemic to the surrounding islands of Flores in Indonesia (including Komodo, Lembata, and Pantar), and formerly Flores itself. Its natural habitat is subtrop ...

'', ''

Palawanomys The Palawan soft-furred mountain rat (''Palawanomys furvus'') is a species of rodent in the family Muridae. It is the only species in the genus ''Palawanomys''. It is found only in Palawan, Philippines, and has been recorded on Mount Mantaling ...

'', ''

Bunomys ''Bunomys'' is a genus of rodent from Sulawesi and Buton Island. Currently, eight species are recognised in two species-groups. Species Genus ''Bunomys'' ''chrysocomus''-group: * Yellow-haired hill rat, ''Bunomys chrysocomus'' Hoffmann, 1887 * ...

'', ''

Nesoromys The Ceram rat (''Nesoromys ceramicus''), also known as the Seram Island mountain rat, is a species of rodent in the family Muridae. It is found only in Seram Island, Indonesia, where it has been recorded on Mount Mansuela. It is the only speci ...

'', ''Stenomys'', ''

Taeromys ''Taeromys'' is a genus of rodent in the family Muridae found exclusively in Sulawesi, Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Oce ...

'', ''

Paruromys The Sulawesi giant rat (''Taeromys dominator'') is a species of rodent in the family Muridae. The species is endemic to Sulawesi in Indonesia, where it inhabits forests at elevations from sea level to the tree line. It is frugivorous and semiarb ...

'', ''

Abditomys The Luzon broad-toothed rat (''Abditomys latidens'') is a species of rodent in the family Muridae. It is endemic to central and northern Luzon in the Philippines. It is the only member of the genus Genus (; : genera ) is a taxonomic rank a ...

'', ''

Tryphomys The Luzon short-nosed rat (''Tryphomys adustus'') is a species of rodent in the family Muridae. It is the only species in the genus ''Tryphomys''. It is found only in the Philippines The Philippines, officially the Republic of the Phili ...

'', ''

Limnomys ''Limnomys'' is a genus of rodent in the family Muridae endemic to Mindanao, Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western ...

'', ''

Tarsomys ''Tarsomys'' is a genus of rodent in the family Muridae found exclusively in Mindanao, Philippines. The Mammal Diversity Database of the American Society of Mammalogists The American Society of Mammalogists (ASM) was founded in 1919. Its prima ...

'', ''

Bullimus ''Bullimus'' is an endemic genus of rodent from the Philippines, as first catalogued by Mearns, in 1905. Species Genus ''Bullimus'' * Bagobo rat, ''Bullimus bagobus'', Mindanao * Carleton's forest rat, ''Bullimus carletoni'', Luzon Luzon ...

'', ''

Apomys ''Apomys'', commonly known as earthworm mice, is a genus of rodent endemic to the Philippines. Mice belonging to this genus are generally called Philippine forest mice and can be found on most islands of the Philippines The Philippines, ...

'', ''

Millardia ''Millardia'' is a genus of rodent in the family Muridae native to South Asia and Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in n ...

'', ''

Srilankamys The Ohiya rat (''Srilankamys ohiensis''), or Sri Lanka bi-colored rat, is a species of rodent in the family Muridae. It is the only species in the genus ''Srilankamys''. It is found only in Sri Lanka Sri Lanka, officially the Democratic S ...

'', ''

Niviventer ''Niviventer'' is a genus of rodent in the family Muridae endemic to Southeast Asia. It contains the following species: * Anderson's white-bellied rat, ''Niviventer andersoni'' * Brahma white-bellied rat, ''Niviventer brahma'' * '' Niviventer b ...

'', ''

Maxomys ''Maxomys'' is a genus of rodents, widespread in Southeast Asia. They are mid-sized rodents, similar to rats, that live on the ground of tropical rainforests. There they build nests, padded with fallen leaves from trees. They feed on roots, falle ...

'', ''

Leopoldamys ''Leopoldamys'' is a genus of rodents in the family Muridae The Muridae, or murids, are either the largest or second-largest family of rodents and of mammals, containing approximately 870 species, including many species of mice, rats, and gerb ...

'', '' Berylmys'', ''

Mastomys ''Mastomys'' is a genus of rodent in the family Muridae endemic to Africa. It contains eight species: * Angolan multimammate mouse (''M. angolensis'') * Awash multimammate mouse or Awash mastomys (''M. awashensis'') * Southern multimammate mouse ...

'', ''

Myomys Verreaux's mouse or Verreaux's white-footed rat (''Myomyscus verreauxii'') is a species of rodent in the family Muridae. It is the only species in the genus ''Myomyscus''. Other species that had been previously assigned to ''Myomyscus'' are now c ...

'', ''

Praomys ''Praomys'' is a genus of rodent in the family Muridae endemic to Sub-Saharan Africa Sub-Saharan Africa is the area and regions of the continent of Africa that lie south of the Sahara. These include Central Africa, East Africa, Southern A ...

'', ''

Hylomyscus ''Hylomyscus'' is a genus of rodent in the family Muridae endemic to Africa. It contains 21 species divided into six species groups: *''H. aeta'' group **Beaded wood mouse, ''Hylomyscus aeta'' **Mount Oku wood mouse, ''Hylomyscus grandis'' *'' ...

'', '' Heimyscus'', '' Stochomys'', ''

Dephomys ''Dephomys'' is a genus of rodent in the family Muridae endemic to Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including ad ...

'' and ''

Aethomys ''Aethomys'' is a genus of rodent from Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 2 ...

''. The genus ''Rattus'' proper contains 64

extant species Neontology is a part of biology that, in contrast to paleontology, studies and deals with living (or, more generally, '' recent'') organisms. It is the study of extant taxa (singular: extant taxon): taxa (such as species, genera and families) wi ...

. A subgeneric breakdown of the species has been proposed, but does not include all species.

Species

Phylogeny

The following phylogeny of selected ''Rattus'' species is from .

Fossil species

In contrast to the large number of living species, as of 2024, just four fossil species have been placed in ''Rattus'' proper: * ''Rattus baoshanensis'' - Late

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

Thailand * ''Rattus pristinus'' - Early Pleistocene China * ''Rattus miyakoensis'' - Late Pleistocene Japan

References

{{Authority control . Rodent genera Taxa named by Gotthelf Fischer von Waldheim Extant Pleistocene first appearances