Desert Spiny Lizard (Sceloporus magister)

(Fig. 01)
Picture Notes: I found this guy while hiking a wash near the Crescent Mine off the southern side of Nipton Road on 04/04/2013 (Fig. 01). While walking around an old abandoned mine head structure, just south of the Crescent mine, my hiking partner “Buster” Brown spotted him sunning himself about five feet up the side of one of the support beams (Fig. 02). Once he spotted us he quickly ran down and scurried to a spot near some bushes about 20 feet away (Fig. 03). The picture in (Fig. 04) is of another one that I saw a week later while hiking near Cold Creek, Nevada. He was sunning on top of a concrete foundation and quickly ran underneath it when I approached. After waiting patiently for about five minutes, he stuck his head out to look around, but wouldn't come out. The final pictures in (Fig. 05) were taken on a hike to the La Madre Spring hike in the Ls Madre Wilderness Area inside Red Rock Canyon Park.
(Fig. 02)
Description: Sceloporus magister, also known as the desert spiny lizard, is a reptile of the family Phrynosomatidae. This genus includes some of the most commonly seen lizards in the United States. Over 90 species in this genus currently are organized in to 21 species groups. Their relationships to each other are currently under review. Another member of this genus is Sceloporus occidentalis, also known as the Western Fence Lizard.
This stocky lizard can be up to 12 inches long, including its tail. It has large, pointed, keeled, overlapping scales. Base coloration is gray, tan, or brown. In the southern subspecies (magister) males often have a large longitudinal purple patch or bar on the mid-dorsum. Because the ventral abdomen of an adult is characteristically blue, it is also known as the blue-belly. Notice the edge of the blue underbelly near the head in (Fig. 01). During the breeding season, females may have orangeish or reddish heads. Spiny lizards can change their color to be darker during cool times (thus absorbing more heat from the sun) and lighter during warm times (thus reflecting more of the solar radiation). Also, spiny lizard species living in the cooler, higher elevations are darker.
Native to the Chihuahuan and Sonoran Deserts, it is found in the states of Arizona, California, Texas, New Mexico, Nevada, and Utah. Its elevation range extends from sea level to 7,000 feet in a variety of arid mountainous habitats, especially Joshua tree, palm oasis, desert succulent shrub, creosote scrub and rocky desert washes - water is not required.
It is usually encountered on lower slopes, bajadas, plains, and low valleys, often in the branches of trees or in the vicinity of ground cover such as wood piles, rock piles, and packrat nests. When I first observed the lizard in these pictures, he was sunning himself on the side of an old mine head structure. When approached it is often heard before it is seen as it scratches and claws the bark en route to the opposite side of a trunk or branch. It flees down into the inner tangles of pack rat nests, rock crevices, or burrows when threatened. It has a strong jaw and often bites when captured.
Hibernating during the cold months of winter and late fall, they are active from April to October, though higher-elevation populations become active a little later. The lizards are diurnal and remain active, or at least visible, on conspicuous elevated sunlit perches throughout the day. During the hottest weather they may retreat to cover in the middle of the day.
(Fig. 03)
(Fig. 04)
(Fig. 05)