Octodontidae is a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

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 na ...

s, restricted to southwestern

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 southe ...

. Fourteen species of octodontid are recognised, arranged in seven

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

. The best known species is the

common degu The common degu (''Octodon degus''; ), or, historically, the degu, is a small hystricomorpha rodent endemic to the Chilean matorral ecoregion of central Chile. The name ''degu'' on its own indicates either the entire genus ''Octodon'' or, more ...

, ''Octodon degus''. Octodontids are medium-sized rodents, ranging from in body length. They have long, silky, fur, which is typically brownish in color, and often paler on the underside. The name 'octodont' derives from the wear pattern of their teeth, which resembles a figure 8. Most are nocturnal, social, burrowing animals, though the degu is largely diurnal. They are

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

, eating

tuber Tubers are a type of enlarged structure used as storage organs for nutrients in some plants. They are used for the plant's perennation (survival of the winter or dry months), to provide energy and nutrients for regrowth during the next growin ...

s, bulbs, and

cactus A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek ...

es. Some authors have suggested that the octodontids should be reclassified in the order

Lagomorpha The lagomorphs are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (hares and rabbits) and the Ochotonidae ( pikas). The name of the order is derived from the Ancient Greek ''lagos'' (λαγ ...

, but this has not been supported by further analyses. Older literature includes the

tuco-tuco A tuco-tuco is a neotropical rodent in the family Ctenomyidae.Parada, A., G. D’Elia, C.J. Bidau, and E.P. Lessa. 2011. Species Groups and the Evolutionary Diversification of Tuco-Tucos, genus ''Ctenomys'' (Rodentia: Ctenomyidae). ''Journal of M ...

s in the family, as the subfamily Ctenomyinae, but these animals are normally now treated as a separate family,

Ctenomyidae A tuco-tuco is a neotropical rodent in the family Ctenomyidae.Parada, A., G. D’Elia, C.J. Bidau, and E.P. Lessa. 2011. Species Groups and the Evolutionary Diversification of Tuco-Tucos, genus ''Ctenomys'' (Rodentia: Ctenomyidae). ''Journal of M ...

. There is some evidence that evolution within the family may have resulted from

polyploidy Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei ( eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contain ...

. The

red viscacha rat The plains viscacha rat, plains vizcacha rat, red viscacha rat, or red vizcacha rat (''Tympanoctomys barrerae'') is a species of rodent in the family Octodontidae native to Argentina. It is one of three species in the genus '' Tympanoctomys''. D ...

, ''Tympanoctomys barrerae'', is tetraploid, with 102

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

s, and the recently described

golden viscacha rat The golden viscacha rat or golden vizcacha rat (''Pipanacoctomys aureus'') is the single species of the genus ''Pipanacoctomys'' of the rodent family Octodontidae. It has 92 chromosomes and has been regarded as tetraploid ( 4x = 2n).Gallardo, M ...

''Pipanacoctomys aureus'' has 92. Members of the genus ''

Aconaemys ''Aconaemys'' is a genus of rodent in the family Octodontidae. It contains the following species: * Chilean rock rat (''Aconaemys fuscus'') * Porter's rock rat (''Aconaemys porteri'') * Sage's rock rat Sage's rock rat (''Aconaemys sagei'') is ...

'' are referred to as rock rats, and members of genera ''

Octodon ''Octodon'' is a genus of octodontid rodents native to South America, in particular in the Chilean Andes. The best-known member is the common degu, ''O. degus'', which is kept as a pet in various countries. Two of the four species of degus are ...

'' and ''

Octodontomys The mountain degu (''Octodontomys gliroides'') is a species of rodent in the family Octodontidae. It is the only species in the genus ''Octodontomys''. It is found in the foothills of the Andes in Argentina, Bolivia and Chile. Description The ...

'' are called degus, though the name degu on its own historically implied ''O. degu''. The single member of ''

Spalacopus The coruro (''Spalacopus cyanus'') is a species of rodent in the family Octodontidae. It is the only species in the genus ''Spalacopus''. The species is endemic to central Chile, where it has been found in a wide variety of habitats, from coas ...

'', ''S. cyanus'', is called the

coruro The coruro (''Spalacopus cyanus'') is a species of rodent in the family Octodontidae. It is the only species in the genus ''Spalacopus''. The species is endemic to central Chile, where it has been found in a wide variety of habitats, from coas ...

. Members of the other genera are called viscacha rats.

List of species

Genus ''

'' Ameghino, 1891 (Andean rock rats). *Species ''

Aconaemys fuscus The Chilean rock rat (''Aconaemys fuscus'') is a species of rodent in the family Octodontidae. It is found in the high Andes of Argentina and Chile. Description The Chilean rock rat is a short-tailed rodent. Rock rats in the genus '' Aconaemys'' ...

'' ( Waterhouse, 1842) (Chilean rock rat). Andes of Chile and Argentina. *Species ''

Aconaemys porteri Porter's rock rat (''Aconaemys porteri'') is a species of rodent in the family Octodontidae. It is found in Argentina and Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the south ...

Thomas Thomas may refer to: People * List of people with given name Thomas * Thomas (name) * Thomas (surname) * Saint Thomas (disambiguation) * Thomas Aquinas (1225–1274) Italian Dominican friar, philosopher, and Doctor of the Church * Thomas the A ...

, 1917. (Porter's rock rat) Andes of Chile and Argentina. *Species '' Aconaemys sagei'' (Pearson, 1984) (Sage's rock rat). Andes of Chile and Argentina. Genus ''

'' ( Wagler, 1832). *Species '' Spalacopus cyanus'' Molina, 1782. (Coruro). Central Chile. Genus ''

Bennett Bennett may refer to: People *Bennett (name), including a list of people with the surname and given name Places Canada * Bennett, Alberta *Bennett, British Columbia * Bennett Lake, in the British Columbia and Yukon Territory **Bennett Range **Benn ...

, 1832 (typical degus). *Species '' Octodon bridgesii'' Waterhouse, 1844 (Bridges's degu). Western Chile *Species ''

Octodon degus The common degu (''Octodon degus''; ), or, historically, the degu, is a small hystricomorpha rodent endemic to the Chilean matorral ecoregion of central Chile. The name ''degu'' on its own indicates either the entire genus '' Octodon'' or, more ...

'' (Molina, 1782) (Common degu). Western Chile. *Species ''

Octodon lunatus The moon-toothed degu (''Octodon lunatus'') is a species of rodent in the family Octodontidae. It is endemic to Chile, occurring in mountainous areas along the Pacific coast in the central part of the country. Biology and physiology Unlike its c ...

'' Osgood, 1943 (Moon-toothed degu). Western Chile. *Species '' Octodon pacificus'' Hutterer, 1994 (Isla Mocha degu). Isla Mocha, off western Chile. *Species ''

Octodon ricardojeda Ricardo Ojeda's degu (''Octodon ricardojeda'') is a species of rodent in the family Octodontidae. It is found in a small portion of eastern Chile and western Argentina, being the only degu found outside of Chile. It was named after Argentine mam ...

'' D'Elía, Teta, Verzi, Cadenilla, & Patton, 2020 (Ricardo Ojeda's degu). Andes of Chile and Argentina. Genus ''

'' Palmer, 1903. *Species '' Octodontomys gliroides'' Gervais & D'Orbigny, 1844. (Mountain degu) Andes of northwestern Argentina, extreme northeastern Chile and western Bolivia. Genus ''

Octomys The mountain viscacha rat or mountain vizcacha rat (''Octomys mimax''), historically viscacha rat or vizcacha rat, is a species of rodent in the family Octodontidae. It is endemic to Argentina. It is the only living species within the genus ' ...

, 1920. *Species '' Octomys mimax'' Thomas, 1920 (Mountain viscacha rat). Andes of Argentina. Genus ''

Pipanacoctomys The golden viscacha rat or golden vizcacha rat (''Pipanacoctomys aureus'') is the single species of the genus ''Pipanacoctomys'' of the rodent family Octodontidae. It has 92 chromosomes and has been regarded as tetraploid ( 4x = 2n).Gallardo, M ...

'' Mares et al., 2000. *Species ''

Pipanacoctomys aureus The golden viscacha rat or golden vizcacha rat (''Pipanacoctomys aureus'') is the single species of the genus ''Pipanacoctomys'' of the rodent family Octodontidae. It has 92 chromosomes and has been regarded as tetraploid ( 4x = 2n).Gallardo, M. ...

'' Mares et al., 2000 (Golden viscacha rat). Catamarca Prov., Argentina. Genus ''

Tympanoctomys ''Tympanoctomys'' is a genus of rodent in the family Octodontidae. There are three extant species in the genus: '' T. barrerae'', '' T. kirchnerorum'' and '' T. loschalchalerosorum''. ''T. loschalchalerosorum'' was formerly considered to be mono ...

'' Yepes, 1942. *Species ''

Tympanoctomys barrerae The plains viscacha rat, plains vizcacha rat, red viscacha rat, or red vizcacha rat (''Tympanoctomys barrerae'') is a species of rodent in the family Octodontidae native to Argentina. It is one of three species in the genus ''Tympanoctomys''. Des ...

'' (Lawrence, 1941) (Plains viscacha rat or Red viscacha rat). Scattered localities in western Argentina. *Species '' Tympanoctomys loschalchalerosorum'' (Mares, Braun, Barquez & Diaz, 2000) (Chalchalero viscacha rat).

Salinas Grandes The Salinas Grandes ('Salina' is a spanish word for salt flat) is a large salt flat in central-northern Argentina, spanning the borders of four provinces ( Córdoba, Catamarca, La Rioja and Santiago del Estero), at an average altitude of abov ...

, Argentina. *Species '' Tympanoctomys kirchnerorum'' (Teta, Pardiñas, Sauthier & Gallardo, 2014) (Kirchner's viscacha rat). western Argentina. *Species †'' Tympanoctomys cordubensis''

References

*Gallardo, M. H. ''et al.''. (2004). Whole-genome duplications in South American desert rodents (Octodontidae). ''Biological Journal of the Linnean Society, 82'', 443-451.

External links

Deguworld.com
- The Internet's Degu Expert, providing information, a forum and advice on raising your Degus. *http://www.degutopia.co.uk {{Taxonbar, from=Q852773 Hystricognath rodents Rodent families Extant Miocene first appearances Taxa named by George Robert Waterhouse