The Desert Spiny Lizard is indigenous to the desert southwest and is found to live from sea level to a 5000' foot elevation which includes the lovely Sedona Arizona USA.
These are medium to large lizards with snout-vent lengths ranging from 2¼ to 5¼ inches (63 to 138 mm). These robust lizards have keeled, pointed scales. Background color is usually subdued gray, tan, or blue with a striking wide, purple stripe down the back and single yellow scales scattered on the sides (S. magister), or scattered turquoise scales mixed with tan and brown on the back and sides (S. clarkii). Both species have a dark collar under or around the neck; males have vivid blue throats and under-bellies. Females develop orange to red heads during the breeding season.
Like many other lizards, spiny lizards exhibit metachromatism, which is color change as a function of temperature. When it is cooler, colors are much darker than when the temperature is high. Darker colors increase the amount of heat absorbed from the sun and lighter colors reflect solar radiation.
This curious look is probably a serious look!