Octodontidae is a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

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, restricted to southwestern

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. Fourteen species of octodontid are recognised, arranged in seven

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

. 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, mor ...

, ''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 evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat n ...

, eating

tuber Tubers are a type of enlarged structure that plants use as storage organs for nutrients, derived from stems or roots. Tubers help plants perennate (survive winter or dry months), provide energy and nutrients, and are a means of asexual reproduc ...

s, bulbs, and

cactus A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

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

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Lagomorpha The lagomorphs () are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (rabbits and hares) and the Ochotonidae ( pikas). There are 110 recent species of lagomorph, of which 109 species in t ...

, 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. Tuco-tucos belong to the only living genus of the family Ctenomyidae, ''Ctenomys'', but they include approximately 60 different species. The common name, "tuco-tuco", comes from the " ...

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. Tuco-tucos belong to the only living genus of the family Ctenomyidae, ''Ctenomys'', but they include approximately 60 different species. The common name, "tuco-tuco", comes from the " ...

. 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 two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one fro ...

. 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''. Des ...

, ''Tympanoctomys barrerae'', has been proposed to be a tetraploid, with 102

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

s. However, subsequent studies have shown that the increased genome size is due to expansions of repetitive DNA elements. Members of the genus '' Aconaemys'' 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 n ...

'' and ''

Octodontomys The mountain degu (''Octodontomys gliroides''), also known as the Andean degu, 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, Boli ...

'' are called degus, though the name degu on its own historically implied ''Octodon 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 coast ...

'', ''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 coast ...

. Members of the other genera are called 'viscacha rats'.

List of species

Genus '' Aconaemys'' Ameghino, 1891 (Andean rock rats). *Species '' Aconaemys fuscus'' ( Waterhouse, 1842) (Chilean rock rat). Andes of Chile and Argentina. *Species '' Aconaemys porteri''

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. (Cururo). Central Chile. Genus ''

'' Bennett, 1832 (typical degus). *Species '' Octodon bridgesii'' Waterhouse, 1844 (Bridges's degu). Western Chile *Species '' Octodon degus'' (Molina, 1782) (Common degu). Western Chile. *Species '' Octodon lunatus'' Osgood, 1943 (Moon-toothed degu). Western Chile. *Species '' Octodon pacificus'' Hutterer, 1994 (Isla Mocha degu). Isla Mocha, off western Chile. *Species '' Octodon ricardojeda'' 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'' 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: ''Tympanoctomys barrerae, T. barrerae'', ''Tympanoctomys kirchnerorum, T. kirchnerorum'' and ''Tympanoctomys loschalchalerosorum, T. l ...

'' Yepes, 1942. *Species '' Tympanoctomys barrerae'' (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, 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 {{Authority control 8 (number) Caviomorpha Rodent families Extant Miocene first appearances Taxa named by George Robert Waterhouse