Phrynosomatidae

Zebra-tailed lizards (Callisaurus) are a genus of phrynosomatid lizards endemic to the southwestern United States and northwestern Mexico.

This particular individual is an adult male Nevada Zebra-tailed Lizard, (Callisaurus draconoides myurus). This subspecies is found in Nevada not far from the California border north of Honey Lake, where it might occur in washes along the border near Smoke Creek. These lizards reach a length of 2.5-4 inches (6-10cm) from snout to vent, up to almost 9 inches including tail.

They live in open sandy desert washes, desert pavement, and hard pan, with scant widely-spaced vegetation and open areas. They are also sometimes found in wind-blown sand dunes near hard-packed ground. Their diet consists of small invertebrates such as insects and spiders, small lizards and occasional plant material.

These diurnal lizards are well adapted to living in desert areas, tolerant of high temperatures they are often seen basking on rocks, even on extremely hot afternoons.
They are also possibly the fastest desert lizards, able to run very quickly as they have long legs and streamlined body. After speeding away, this lizard sometimes stops far ahead in the open, but it will also run to the far side of a bush, out of view, or into a bush or burrow for protection. Before running, a lizard may curl the tail up towards the back, exposing the black and white bars. They then wag it nervously while running and after stopping. This tail display tactic concentrates a predator’s attention on the tail, which, if attacked and broken off, can grow back.

Photo taken by eaross

Regal Horned Lizard - Phrynosoma solare | ©Jason Penney   (Tohono O’odham Indian Reservation, southwest Arizona, US)

Phyrnosoma solare (Phrynosomatidae) are among the larger species of Horned Lizard. Their Latin name is derived from the meaning “rays of the sun” by referring to four large occipital horns at the base of the head continuous with six temporal horns, form a large crown of ten sharp, pointed horns along the base of the head.

American group of Regal Horned lizards have evolved an exceptionally bizarre defense against predators: when under threat they can restrict blood flow from the head until mounting pressure ruptures small blood vessels in and around the eyes, resulting in a spurt of blood that may leap a meter (3 ½ feet) or more [source].

Baja Blue | ©Seth Patterson

A Baja Blue Rock Lizard, Petrosaurus thalassinus (Reptilia - Squamata - Lacertilia - Phrynosomatidae) found in Baja California Sur, Mexico. 

Petrosaurus thalassinus is restricted to the Cape region of Baja California Sur, where it occurs in at least four locations: one in Sierra La Laguna and accompanying regions, one in the Sierra La Trinidad, the other in the islands of Espiritu Santo and Partida Sur.