Great Basin Whiptail (Aspidoscelis tigris)

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(Fig. 01)
Picture Notes: On 08/09/2014, while hiking near the Willow Springs Picnic Area inside Redrock Canyon looking for some pictographs, I spotted a Great Basin Whiptail lizard (Fig. 01) in some brush ahead of me attempting to capture a caterpillar. He spent the first couple of minutes sizing up his victim (Fig. 02) before actually latching on with a big bite (Fig. 03). When I attempted to move closer for a better shot he scurried off. Climbing up and around a large boulder, I found him wrestling its victim in an open area of the rock.  As seen in the next series of photos (Figs. 04-07), he then spent the next 10 minutes wrangling in and devouring this tempting morsel. As you can see in (Fig. 06), he is sucking every last ounce of “juice” out of him. Having nearly completed this huge meal, notice in (Fig. 07) how much fatter his body appears.
(Fig. 02)
(Fig. 03)
(Fig. 04)
(Fig. 05)
(Fig. 06)
(Fig. 07)
Description: Great basin Whiptail (Aspidoscelis tigris) as a species is slim-bodied with a long slender tail, a thin snout, and large symmetrical head plates, and can grow to 2 3/8 - 5 inches long snout to vent, and up to around 13 inches total length. Depending on the individual, Western Whiptails may appear to have a light ground color that is marked by a dark reticulated pattern, or they may appear to have a dark ground color that is marked by numerous light colored spots. Regardless, there is always a striped pattern down the full length of their body that is apparent. The four stripes are a light tan, gray or cream color and extend dorsolaterally from the base of the head towards the tail. The stripes are most prominent in juveniles, and they tend to fade posteriorly in adults. The previously described pattern of contrasting spots and markings extends onto the base of the tail, but the color darkens towards the tip, becoming a more bluish-gray. Western Whiptails have fine, granular scales dorsally, and large rectangular scales arranged in 8 rows ventrally. The lower limbs of these lizards have a distinct scalation, being covered anteriorly with large, smooth scales that contrast with the granular scales elsewhere on the limbs. In fact, the genus name loosely translated means "bearing armored legs". The long tail of the Western Whiptail can be more than twice the snout-vent length if it is unbroken. There is a fair chance that a Western Whiptail may be encountered with a tail that is regenerating, as they will readily lose their tail to predators and would be captors.
Western Whiptails mate in the spring, laying 1-4 eggs in June or July, which in turn hatch in August. The juveniles resemble the adults but are more vividly colored (including the tail, which is more blue in coloration). The back and sides are grey, tan, or brown, marked with dark spots or bars or mottling, which is often very sharply defined. Dark marks on the sides often form vertical bars. The belly is made of large, smooth, rectangular scales in 8 lengthwise rows. Often there are reddish patches on the sides of the belly. The throat is pale with with obscure black spots. Scales on the back are small and granular, and scales on the tail are keeled. The tail can reach up to two times the length of the body. They can be wary and very active, moving with abrupt stops and starts with side-to-side head movement and tongue flicking. Often seen digging rapidly when foraging. Typically foraging near cover, they are very difficult to approach and are capable of quick bursts of speed into heavy brush or holes. They like to eat small invertebrates, especially spiders, scorpions, centipedes, termites, and small lizards.
The species (Aspidoscelis tigris) ranges from North central Oregon and southern Idaho, south through California and Nevada to Baja California, and east into Utah, Colorado, Arizona, New Mexico, and west Texas. From sea level to 7,000 feet, they are found in a variety of ecosystems, primarily hot and dry open areas with sparse foliage - deserts, chaparral, sagebrush, woodland, and riparian areas. They generally avoid areas with dense growth.