Reptilia - Squamata - Xenosauridae
Parent taxon: Anguimorpha according to J. L. Conrad 2006
See also Alifanov 1993, Alifanov 2000, Averianov et al. 2005, Carroll 1988, Cope 1871, Cope 1875, Estes 1964, Estes 1983, Estes and Berberian 1970, Estes et al. 1988, Frank and Ramus 1996, Gadow 1898, Gao and Fox 1996, Gao and Nessov 1998, Kuhn 1946, Kuhn 1966, Lee and Caldwell 2000, McDowell and Bogert 1954, Peng et al. 2001, Perrier 1928, Seiffert 1975 and Smith 2006
Sister taxa: Anguiformes, Barlochersaurus, Carusioidea, Chometokadmon, Entomophontes, Hodzhakuliidae, Merkurosaurus, Monstersauria, Necrosauridae, Palaeovaranidae, Paravaranidae, Restes, Varaniformes
Subtaxa: Exostinus Nordenosaurus Shestakovia Xenosaurinae Xenostius
Type: Xenosaurus
Ecology: carnivore
Distribution:
• Miocene of United States (1: Nebraska collection)
• Oligocene of United States (1: Colorado)
• Eocene of United States (2: Wyoming)
• Paleocene of United States (2: Montana, Wyoming)
• Cretaceous of Canada (3: Alberta), India (1), Mexico (1), Mongolia (1), the Russian Federation (2), United States (18: Montana, South Dakota, Texas, Utah, Wyoming)
Total: 32 collections including 36 occurrences