Triisodontidae

Triisodontids Temporal range: Early Paleocene to Late Eocene
Triisodon quivirensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Mesonychia
Family:	†Triisodontidae Trouessart, 1904
Type genus
Triisodon
Genera
†Eoconodon †Goniacodon †Stelocyon †Triisodon

Triisodontidae (literally "three equal teeth") is an extinct, possibly invalid family of mesonychian placental mammals. Most triisodontid genera lived during the early Paleocene in North America, but the genus Andrewsarchus (if it is a mesonychian, and not an artiodactyl) is known from the late Eocene of Asia.^[1] Triisodontids were the first relatively large predatory mammals to appear in North America following the extinction of the dinosaurs.^[2] They differ from other mesonychian families in having less highly modified teeth.^[3]

Because of their comparatively simpler teeth, the Triisodontids are regarded as basal mesonychids. A recent study found them to be a paraphyletic assemblage of stem-mesonychians.^[4]

References

1. McKenna, M. C, and S. K. Bell (1997). Classification of Mammals Above the Species Level. Columbia University Press. ISBN 0-231-11012-X.
2. Clemens, W.A. and T.E. Williamson (2005). "A new species of Eoconodon (Triisodontidae, Mammalia) from the San Juan Basin, New Mexico". Journal of Vertebrate Paleontology 25 (1): 208–213. doi:10.1671/0272-4634(2005)025[0208:ANSOET]2.0.CO;2. ISSN 0272-4634.
3. Matthew, W.D. (1937). "Paleocene faunas of the San Juan Basin, New Mexico". Transactions of the American Philosophical Society (American Philosophical Society) 30: 1–510. doi:10.2307/1005521. JSTOR 1005521.
4. SHELLEY, Sarah L, RESOLVING THE HIGHER-LEVEL PHYLOGENETIC RELATIONSHIPS OF �75,,62'217,'$(´�³&21'</$57+5$´�:,7+,1 PLACENTALIA, October 2015