Crotaphytidae Explained

The Crotaphytidae, or collared lizards, are a family^{[1] [2] [3]} of desert-dwelling reptiles native to the Southwestern United States and northern Mexico. Alternatively they are recognized as a subfamily, Crotaphytinae, within the clade Pleurodonta. They are very fast-moving animals, with long limbs and tails; some species are capable of achieving bipedal running at top speed. This species is carnivorous, feeding mainly on insects and smaller lizards. The two genera contain 12 species.

They may be related to the extinct Arretosauridae of Paleogene Asia due to similar jaw morphologies, though other studies classify the Arretosauridae in Acrodonta with other Old World iguanians.^{[4] [5]}

Technical characters

• Femoral pores present
• Interparietal scale small (distinctly smaller than ear opening)
• Never have an enlarged middorsal scale row or fringe
• Never have a divided rostral scale
• No bony spines or projecting ridges on their heads
• No scales projecting over their ears, and no scales forming a prominent fringe on sides of toes as in Phrynosomatidae

Species

Image	Genus	Living species
	Gambelia ^[6] ^[7] (leopard lizards)	Cope's leopard lizard – Gambelia copeii blunt-nosed leopard lizard – Gambelia sila long-nosed leopard lizard – Gambelia wislizenii
	Crotaphytus ^[8] (collared lizards)	venerable collared lizard – Crotaphytus antiquus desert collared lizard – Crotaphytus bicinctores common collared lizard – Crotaphytus collaris Dickerson's collared lizard – Crotaphytus dickersonae Grismer's collared lizard – Crotaphytus grismeri Eastern collared lizard – Crotaphytus insularis Sonoran collared lizard – Crotaphytus nebrius reticulated collared lizard – Crotaphytus reticulatus Baja collared lizard – Crotaphytus vestigium

Nota bene

A binomial authority in parentheses indicates that the species was originally described in different genus.

Further reading

• Frost DR, Etheridge RE (1989). A Phylogenetic Analysis and Taxonomy of Iguanian Lizards (Reptilia: Squamata) Univ. Kansas Mus. Nat. Hist. Misc. Publ. 81: 1-62. (Family Crotaphytidae, p. 36).
• Smith HM, Brodie ED Jr (1982). Reptiles of North America: A Guide to Field Identification. New York: Golden Press. 240 pp. . (Subfamily Crotaphytinae, p. 106).

Notes and References

1. Townsend, Ted M. . Mulcahy, Daniel G. . Noonan, Brice P. . Sites, Jack W. Jr . Kuczynski, Caitlin A. . Wiens, John J. . Reeder, Tod W. . 2011 . Phylogeny of iguanian lizards inferred from 29 nuclear loci, and a comparison of concatenated and species-tree approaches for an ancient, rapid radiation . Molecular Phylogenetics and Evolution . 61 . 2 . 363–380 . 10.1016/j.ympev.2011.07.008 . 21787873 .
2. Wiens, John T.. Hutter, Carl R. . Mulcahy, Daniel G. . Noonan, Brice P. . Townsend, Ted M. . Sites, Jack W. Jr. . Reeder, Tod W. . 2012 . Resolving the phylogeny of lizards and snakes (Squamata) with extensive sampling of genes and species . Biology Letters . 8 . 6 . 1043–1046 . 10.1098/rsbl.2012.0703 . 3497141 . 22993238.
3. Pyron, R. Alexander . Burbrink, Frank T. . Wiens, John J. . 2013 . A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes . BMC Evolutionary Biology . 13 . 93 . 10.1186/1471-2148-13-93 . 3682911 . 23627680 . free . 2013BMCEE..13...93P .
4. Alifanov . V. R. . 2012-07-01 . Lizards of the family Arretosauridae Gilmore, 1943 (Iguanomorpha, Iguania) from the Paleogene of Mongolia . Paleontological Journal . en . 46 . 4 . 412–420 . 10.1134/S0031030112040028 . 2012PalJ...46..412A . 119087759 . 1555-6174.
5. Bolet . Arnau . Stubbs . Thomas L . Herrera-Flores . Jorge A . Benton . Michael J . 2022-05-03 . Zhu . Min . Perry . George H . Zhu . Min . The Jurassic rise of squamates as supported by lepidosaur disparity and evolutionary rates . eLife . 11 . e66511 . 10.7554/eLife.66511 . 35502582 . 9064307 . 2050-084X . free .
6. Dahms Tierleben. www.dahmstierleben.de/systematik/Reptilien/Squamata/Iguania/crotaphytidae.
7. www.reptile-database.org.
8. www.reptile-database.org.