Trituberculata is an extinct group of animals existing in the fossil record from about 215 – 85 MYA.[1] It contains the ancestors of Placentalia and Marsupialia; all modern mammals except Monotremata are descended from trituberculates.[2] It is named for the three tubercles (cusps) of the molar teeth (not to be confused with Triconodonta).[3] The clade Trituberculata is not always regarded as a valid one, and it likely does not form a monophyletic group. Instead, some of them may be "true" basal mammals (although not always closest related to each other), while others (such as the symmetrodonts) may fall just outside the therian crown group.

Trituberculata
Temporal range: 200–85 Ma Upper Triassic - Upper Cretaceous
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Theria
Infraclass: Trituberculata
Orders

?Symmetrodonta
Pantotheria
Aegialodontia
Eupantotheria

See also

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References

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  1. ^ McKenna, Malcolm C. (1975), Luckett, W. Patrick; Szalay, Frederick S. (eds.), "Toward a Phylogenetic Classification of the Mammalia", Phylogeny of the Primates: A Multidisciplinary Approach, Boston, MA: Springer US, pp. 21–46, doi:10.1007/978-1-4684-2166-8_2, ISBN 978-1-4684-2166-8, retrieved 2022-06-21
  2. ^ Osborn, Henry Fairfield; Wortman, Jacob Lawson; Peterson, Olof August (1893). "Fossil mammals of the Upper Cretaceous beds. Bulletin of the AMNH ; v. 5, article 17". {{cite journal}}: Cite journal requires |journal= (help)
  3. ^ Matthew, William Diller; Simpson, George Gaylord (1943). "Relationships of the Orders of Mammals". Journal of Mammalogy. 24 (3): 304–311. doi:10.2307/1374832. ISSN 0022-2372.