''Myocastor'' is a genus of rodent that contains the living

nutria The nutria (''Myocastor coypus''), also known as the coypu, is a large, herbivorous, semiaquatic rodent. Classified for a long time as the only member of the family Myocastoridae, ''Myocastor'' is now included within Echimyidae, the family of ...

(or coypu), as well as several fossil species.

Taxonomy

Due to similar cranial morphology, the nutria was once considered a close relative of the Caribbean

hutias Hutias (known in Spanish as jutía) are moderately large cavy-like rodents of the subfamily Capromyinae that inhabit the Caribbean islands, with most species restricted to Cuba and Hispaniola. Twenty species of hutia have been identified, but at ...

and placed together with them in the family Capromyidae. Later, it was more accepted to place it in its own family, the Myocastoridae. Recent molecular studies place them in the family

Echimyidae Echimyidae is the family of neotropical spiny rats and their fossil relatives. This is the most species-rich family of hystricognath rodents. It is probably also the most ecologically diverse, with members ranging from fully arboreal to terr ...

, in the tribe

Myocastorini Myocastorini is a tribe of echimyid rodents, proposed in 2017, and containing the five extant genera '' Callistomys'', '' Hoplomys'', '' Myocastor'', ''Proechimys ''Proechimys'' is a genus of South American spiny rats of the family Echimyida ...

Fossil record

Kerber et al. (2013) recognize the following species as valid: *'' Myocastor columnaris'' (Middle Pleistocene) *'' Myocastor obesus'' (Late Miocene) *'' Myocastor paranensis'' (Late Miocene) Other species described but no longer considered valid include ''Myocastor minor'', ''Myocastor perditus'', and ''Myocastor priscus''.

References

{{Taxonbar, from=Q10795801 Rodent genera Mammal genera with one living species Taxa named by Robert Kerr (writer) Echimyidae