Coryphodontidae is an extinct family of

pantodont Pantodonta is an extinct suborder (or, according to some, an order) of eutherian mammals. These herbivorous mammals were one of the first groups of large mammals to evolve (around 66 million years ago) after the end of the Cretaceous. The la ...

mammals known from the

Late Paleocene The Thanetian is, in the International Commission on Stratigraphy, ICS Geologic timescale, the latest age (geology), age or uppermost stage (stratigraphy), stratigraphic stage of the Paleocene epoch (geology), Epoch or series (stratigraphy), Serie ...

to the

Middle Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn ...

of Eurasia and North America. Gobiatherium major

The type genus ''

Coryphodon ''Coryphodon'' (from Greek κορῦφὴ, "point", and ὀδοὺς, "tooth", meaning ''peaked tooth'', referring to "the development of the angles of the ridges into points n the molars") is an extinct genus of pantodonts of the family Corypho ...

'' is known from around the Paleocene-Eocene transition in Europe, western United States, northern Canada, and eastern Asia. The remaining genera are known exclusively from the middle Eocene of Asia. The coryphodontids are related to the pantolambdids. ''Coryphodon'' are large, derived pantodonts first described in the mid-19th century, but no intermediate stages leading to their unusual upper molars are known. The last known species of ''Coryphodon'' have

bilophodont The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone to ...

molars similar to later, more derived coryphodontids, and, most likely, ''Coryphodon'' is the primitive sister taxon to the remaining genera and the entire lineage (or lineages) originated from within this genus. Two coryphodontids considerably larger than ''Coryphodon'' but endemic to China, '' Asiocoryphodon'' and '' Heterocoryphodon'', have more advanced bilophodont dentition. '' Metacoryphodon'' is morphologically transitional between ''Coryphodon'' and ''Eudinoceras''. Corypohodontids were slow-growing and long-living animals, and studies of a large sample of individuals from a single locality, assumed to be from the same population, suggest that coryphodontids had a

polygynous Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women. Incidence Polygyny is more widespread in Africa than in any ...

social structure in which males and females reached sexual maturity at different ages.

Notes

References

* * * * * * * * * * * * * * {{Taxonbar, from=Q15728803 Pantodonts Paleocene first appearances Eocene extinctions Prehistoric mammal families