Phrynosomatidae

The Phrynosomatidae are a diverse family of lizards, sometimes classified as a subfamily (Phrynosomatinae), found from Panama to the extreme south of Canada. Many members of the group are adapted to life in hot, sandy deserts, although the spiny lizards prefer rocky deserts or even relatively moist forest edges, and the short-horned lizard lives in prairie or sagebrush environments. The group includes both egg-laying and viviparous species, with the latter being more common in species living at high elevations.[2]

Phrynosomatidae Temporal range: Late Cretaceous to recent,
Emerald swift (Sceloporus malachiticus)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Iguania
Clade:	Pleurodonta
Family:	Phrynosomatidae Fitzinger, 1843[1]
Genera
Callisaurus Cophosaurus †Desertiguana Holbrookia Petrosaurus Phrynosoma Sceloporus Uma Urosaurus Uta

The earliest fossil remains of this group are known from the Late Cretaceous of Mongolia and belong to the genus Desertiguana.[3] As phrynosomatids are only known from North America, these remains indicate that phrynosomatids likely had a wider distribution in prehistoric times.