Ricardo Ojeda's degu (''Octodon ricardojeda'') is a species of

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 ...

in the

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 ...

Octodontidae Octodontidae is a family of rodents, restricted to southwestern South America. Fourteen species of octodontid are recognised, arranged in seven genera. The best known species is the common degu, ''Octodon degus''. Octodontids are medium-sized ...

. It is found in a small portion of eastern

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

and western

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

, being the only degu found outside of Chile. It was named after Argentine mammalogist Ricardo Ojeda. It was formerly thought to be a population of Bridge's degu (''O. bridgesii)'' but in 2020, a genomic study found it to be a distinct species. Phylogenetic evidence supports it being the sister species to the

Pacific degu The Pacific degu (''Octodon pacificus''), also known as the Mocha Island degu, is a species of rodent in the family Octodontidae. It is endemic to Mocha Island in Chile. Its natural habitat is subtropical or tropical moist lowland forests. It is ...

(''R. pacificus''), from which it diverged during the early

Pleistocene 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 ...

, about 1.97 million years ago.

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

records of this species are known from Holocene archaeological sites in

Neuquén Neuquén (; ) is the capital city of the Argentine province of Neuquén and of the Confluencia Department, located in the east of the province. It occupies a strip of land west of the confluence of the Limay and Neuquén rivers which form t ...

and Río Negro, Argentina; this indicates that the species had a slightly wider distribution in prehistoric times. In

it inhabits semiopen areas in

southern beech ''Nothofagus'', also known as the southern beeches, is a genus of 43 species of trees and shrubs native to the Southern Hemisphere, found across southern South America (Chile, Argentina) and east and southeast Australia, New Zealand, New Guin ...

forests, such as those found in

Lanín National Park Lanín National Park () is a national park of Argentina, located in the Neuquén Province, with forests of diverse tree varieties, mainly Fagaceae and conifers such as the lenga and the ''Araucaria'', many species of which are not found elsewher ...

, as well as sandy hillocks within patches of ''

Chusquea ''Chusquea'' is a genus of evergreen bamboos in the grass family. Most of them are native to mountain habitats in Latin America, from Mexico to southern Chile and Argentina. They are sometimes referred to as South American mountain bamboos. Unl ...

'' bamboo. Although it is a primarily terrestrial species, it can climb. It is not as of yet known if it excavates the burrows that it inhabits or only occupies those dug by other animals. Due to its small range and being known only from a few localities (although potential unsurveyed habitat exists), it has been recommended that this species be classified as Vulnerable on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

References

{{Taxonbar, from=Q109424155 Octodon Mammals of Patagonia Mammals of Chile Mammals of Argentina Mammals described in 2020