Hydrochoerinae

Hydrochoerinae Temporal range: Late Miocene - Recent

Capybara
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Family:	Caviidae
Subfamily:	Hydrochoerinae J. E. Gray, 1825
Genera
Kerodon †Porcellusignum †Cardiatherium †Phugatherium †Xenocardia †Contracavia †Anatochoerus †Hydrochoeropsis †Nothydrochoerus †Neochoerus †Protohydrochoerus Hydrochoerus

Hydrochoerinae is a subfamily of Caviidae, consisting of two living genera, Hydrochoerus, the capybaras, and Kerodon, the rock cavies. In addition, a number of extinct genera related to capybaras should also be placed in this subfamily. The taxonomy of Hydrochoerinae is confused by the fact that, until recently living capybaras and their extinct relatives were placed in their own family, Hydrochoeridae (e.g. McKenna and Bell, 1997). Recent molecular phylogenetic studies recognize a close relationship between Hydrochoerus and Kerodon (Rowe and Honeycutt, 2002), supporting placement of both genera in a subfamily of Caviidae (Woods and Kilpatrick, 2005). Paleontological classifications have yet to incorporate this new taxonomy, and continue to use Hydrochoeridae for all capybaras, while using Hydrochoerinae for the living genus and its closest fossil relatives such as Neochoerus (Vucetich et al., 2005; Deschamps et al., 2007). The taxonomy of fossil hydrochoerines is also in a state of flux. In recent years, the diversity of fossil hydrochoerines has been substantially reduced (Prado et al., 1998; Vucetich et al., 2005; Deschamps et al., 2007). This is largely due to the recognition that capybara molar teeth show strong variation in shape over the life of an individual (Vucetich et al., 2005). In one instance, material once referred to four genera and seven species on the basis of differences in molar shape is now though to represent differently aged individuals of a single species, Cardiatherium paranense (Vucetich et al., 2005).

References

Deschamps, C.M., A.I. Olivares, E.C. Vieytes and M.G. Vucetich. 2007. Ontogeny and diversity of the oldest capybaras (Rodentia: Hydrochoeridae; late Miocene of Argentina). Journal of Vertebrate Paleontology 27(3):683-692.
McKenna, Malcolm C., and Bell, Susan K. 1997. Classification of Mammals Above the Species Level. Columbia University Press, New York, 631 pp. ISBN 0-231-11013-8
Prado, J.L., E. Cerdeño, and S. Roig-Juñent. 1998. The giant rodent Chapalmatherium from the Pliocene of Argentina: New remains and taxonomic remarks on the Family Hydrochoeridae. Journal of Vertebrate Paleontology 18(4):788-798.
Rowe, D. L. and R. L. Honeycutt. 2002. Phylogenetic relationships, ecological correlates, and molecular evolution within the Cavioidea (Mammalia, Rodentia). Molecular Biology and Evolution, 19:263-277.
Vucetich, M.G., C.M. Deschamps, A.I. Olivares, and M.T. Dozo. 2005. Capybaras, size, shape, and time: A model kit. Acta Palaeontologica Polonica 50(2):259-272. [1]
Woods, Charles A.; Kilpatrick, C. William (16 November 2005). "Infraorder Hystricognathi (pp. 1538-1600)". In Wilson, Don E., and Reeder, DeeAnn M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). pp. 1555-1556. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=13400216.