Chamops

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Chamops
Temporal range: Late Cretaceous-Early Eocene, 84.5–55  Ma
Chamops holotype maxilla.png
Maxilla of the holotype seen from two different angles
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Clade: Polyglyphanodontia
Genus: Chamops
Marsh, 1892
Type species
Chamops segnis
Marsh, 1892
Synonyms
  • Alethesaurus(Gilmore, 1928)
  • Lanceosaurus(Gilmore, 1928)

Chamops is an extinct genus of polyglyphanodontian lizard from the Late Cretaceous-Early Eocene of North America. Fossils have been found in the Hell Creek Formation, Judith River Formation and Polecat Bench Formation of Montana, [1] the Milk River Formation of Alberta, Canada and possibly also the Laramie Formation of Colorado. [2] It is known from only one species, C. segnis. [2] Chamops grew to approximately 0.5 meters (20 inches) long, and 2 kilograms (4 pounds) in weight. Unlike other polyglyphanodonts, Chamops had a more blunt snout. Chamops belonged to the Chamopsiid family of polyglyphanodontian lizards that lived in the Northern Hemisphere during the Late Cretaceous, although there are some possible Chamopsiid genera from South America and the Kem Kem Bone Beds in Morocco. It was originally thought Chamops and kin are related to whiptails, [2] although it is now thought they are more closely related to iguanas. [3]

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References

  1. D. E. Russell. (1967). Le Paleocene continental d'Amerique du nord. Memoires du Museum National d'Histoire Naturelle. Serie C., Sciences de la Terre 16(2):37-99
  2. 1 2 3 Marsh, O.C. (1892). "Notice of new reptiles from the Laramie formation". American Journal of Science. 43.
  3. R. L. Nydam and G. E. Voci. (2007). Teiid-like scincomorphan lizards from the Late Cretaceous (Campanian) of southern Utah. Journal of Herpetology 41(2):211-219