''Essonodon'' is a mammal

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

from the Upper

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

of North America. It was a member of the extinct order

Multituberculata Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, a ...

and lived towards the end of the "age of the

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

s." It is within the suborder

Cimolodonta Cimolodonta is a taxon of extinct mammals that lived from the Cretaceous to the Eocene. They were some of the more derived members of the extinct order Multituberculata. They probably lived something of a rodent-like existence until their ...

and perhaps the family

Cimolomyidae Cimolomyidae is a family of fossil mammal within the extinct order Multituberculata. Representatives are known from the Upper Cretaceous and the Paleocene of North America and perhaps Mongolia. The family is part of the suborder Cimolodonta. Oth ...

. The genus ''Essonodon'' was named by Simpson G.G. in 1927, and is also partly known as ''

Cimolodon ''Cimolodon'' is a genus of the extinct mammal order of Multituberculata within the suborder Cimolodonta and the family Cimolodontidae. Specimens are known from the Late Cretaceous of North America. Systematics The genus ''Cimolodon'' was nam ...

''. The inclusion of this taxon within

is tentative. (Kielan-Jaworowska & Hurum 2001, p. 408). The species: ''Essonodon browni'' has also partly been known as ''Cimolodon nitidus'' (Marsh 1889). Place: Hell Creek, Montana & San Juan Basin, New Mexico & Wyoming (USA)
Age: Maastrichtian (Upper Cretaceous)
This species was a large multituberculate that weighed in at over 2.5 kilograms. Further material has been reported from the Frenchman Formation of

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

References

* Simpson (1927), "Mammalian fauna of the Hell Creek Formation of Montana." ''Amer. Mus. Novit.'' 267, p. 1-7, 6 figs. * Kielan-Jaworowska Z & Hurum JH (2001), "Phylogeny and Systematics of multituberculate mammals." ''Paleontology'' 44, p. 389-429. * Much of this information has been derived fro

MESOZOIC MAMMALS; 'basal'

, Boffius, Boffiidae and

Kogaionidae Kogaionidae is a family of fossil mammals within the extinct order Multituberculata. Representatives are known from the Upper Cretaceous and the Paleocene of Europe. Having started as island endemics on Hateg Island during the Upper Cretaceous, ...

, an Internet directory. Prehistoric mammal genera Cretaceous mammals Cimolodonts Extinct mammals of North America Hell Creek fauna Ojo Alamo Formation {{cretaceous-mammal-stub