Northern Sagebrush Lizard

Sceloporus graciosus graciosus

Northern Sagebrush Lizard

Distribution in Wyoming

 

 

 

 

 

 

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The range of the Northern Sagebrush Lizard is spread across the lower elevations of the Rocky Mountains, from the southern edge of Montana south to northern New Mexico, and west into Washington, Oregon, and California. In Wyoming it is found throughout most of the state at elevations below 6,500 feet and in a disjunct population at 7,500 feet in the Norris Geyser Basin of Yellowstone NP. It inhabits the rocky outcroppings and brushy scrubland in the sagebrush communities of the prairie and desert life zones.

Northern Sagebrush Lizard Northern Sagebrush Lizard

These diurnal lizards do not burrow; they seek safety from predators or shelter from the heat of the day by hiding in rock crevasses and sanctuaries within the interior of small thickets or in the tangled debris at the base of brush and shrubs. They do bask on rocks and logs, but they seem to do so more as a means of thermoregulation to enhance their active lifestyle—rather than lounging in the sun as a form of self-indulgence like the Plateau Lizard. These insectivores are active from May through September, foraging on such delicacies as ants, grasshoppers, moths, and beetles.

Northern Sagebrush Lizard Northern Sagebrush Lizard

In the field, the two diagnostic characteristics to look for are: the black patch on the front shoulder and the black-white-black striping on the rear of the thigh. They are a medium sized lizard with snout-vent lengths of about 2 inches. They have a short, thick neck without gular folds and their head features a blunt snout and a distinct ear opening.

The dorsal surface is covered with strongly keeled and acutely pointed scales—resembling an armor plating of overlapping lance tips. The small scales on the back of the thigh are rounded or granular in shape and they are neither keeled nor overlapping—a trait shared by the slightly larger and polygonal shaped scales of the belly. The gray or brown (occasionally greenish) background is marked with a pair of light gray or white longitudinal stripes along the sides; these extend from behind the eye to halfway down the tail. A second pair of light stripes runs a bit lower along the sides and between the front and hind legs. The darker longitudinal bands on the sides and back are regularly disrupted with asymmetrical black squiggles or dashes. The faint gray midline stripe running down the back is not nearly as prominent as in the Prairie Lizard.

Northern Sagebrush Lizard Northern Sagebrush Lizard

Males have a white ventral surface highlighted with a large pair of elongated, black bordered, bright blue patches between the axillaries of the front and rear legs; they also have a pair of smaller, pale blue blotches on the throat. Females are mostly white beneath, but they may have a faint blue or turquoise tint along the sides of the abdomen and occasionally on the throat. Gravid females may also have splashes of reddish orange on the head, neck, and along the sides.

Mating occurs in early summer and begins with males defending their territories by performing head bobbing and pushup displays which may lead to chasing and fighting. Eventually, receptive females are attracted by the fighting, body posturing, and exhibitions of blue bravado and they present themselves by moving into proximity. The male will bite and hold the female by her neck or shoulder, align his body on top of or adjacent to her, and then curl his hind body under the female and insert a hemipenis into her cloaca. Egg laying begins 1-2 weeks later when the female buries 2-7 eggs in a shallow scrape. Hatching takes 40-60 days and young of the year begin showing up in August (or September if a second clutch has been laid). Reproductive maturity is reached in 2 years.