Inhabits gravelly plains and firm sandy areas. Lives in a burrow more than six feet long and three to four feet deep in the form of a spiral. Wide distribution in the UAE, having been recorded from Habshan, the Dubai Road, AI Ain, the Shwaib/Madam area and Ras al Khaimah.
Colour varies with temperature from greenish yellow when warm to dark, sometimes almost black when cold. Has sharp teeth and strong jaws, but the main defence is a long spiky tail which can be lashed vigorously. Its long claws are used for digging. It can inflate its body and hisses loudly by expelling air when threatened.
Food consists rnainly of vegetation, grasses, leaves etc., but will also eat insects including locusts. Has been seen to pick up sheep droppings, probably to extract undigested seeds.
Reproduces by laying eggs in the sand and leaving them to hatch by the heat of the sun.
Its main desert enemies are the desert monitor (Varanus griceus Arabic 'wirral') and birds of prey. Loss of habitat and destruction by man is making it harder to find.
Length up to two feet.