The Uromastyx is a genus of lizard whose members are better-known as Spiny-tailed lizards, uros, mastigures, or dabb lizards. Uromastykes are primarily herbivorous, but occasionally eat insects, especially when young. They spend most of their waking hours basking in the sun, hiding in underground chambers at daytime or when danger appears. They tend to establish themselves in hilly, rocky areas with good shelter and accessible vegetation.
The species are:
Their size ranges from 14 inches (U. hardwickii) to 36 inches or more (U. aegyptius). Hatchlings or neonates are usually no more than 3-4 inches in length. Like many reptiles, these lizards' colors change according to the temperature; during cool weather they appear dull and dark but the colors become lighter in warm weather, especially when basking; the darker pigmentation allows their skin to soak up more sunlight.
Their spiked tail is muscular and heavy, and can be swung at an attacker with great velocity, usually accompanied by hissing and an open-mouthed display of (small) teeth. Uros generally sleep in their burrows with their tails closest to the opening, in order to thwart intruders.
Uromastyx inhabit a range stretching through most of North Africa, the Middle East and across south-central Asia and into India. This area spreads across 5000 miles and 30 countries. They occur at elevations from sea level to well over 3000 feet. They are regularly eaten, and sold in produce markets, by local peoples. Uromastyx tend to bask in areas with surface temperatures of over 120 °F.
A female Uromastyx can lay anywhere from 5 to 40 eggs, depending on age and species. Eggs are laid approximately 30 days following copulation with an incubation time of 70-80 days. The neonates weigh 4-6 grams and are about snout to vent length. They rapidly gain weight during the first few weeks following hatching.
A field study in Algeria concluded that Moroccan spiny-tailed lizards add approximately of total growth each year until around the age of 8-9 years.
Female uros are smaller and less colorful than males. For example, U. maliensis females are light tan with black dorsal spots, while males are mostly bright yellow with mottled black markings. Females also tend to have shorter claws.
The Mali Uromastyx is considered an ideal species to choose as a pet because they readily adapt to a captive environment. Another good species of Uromastyx that adapts to captivity, and comes in some beautiful color varieties, is Uromastyx ocellata ornata. Artificial UVB/UVA light and vitamin supplements must be balanced with proper food and nutrition. Proper enclosures can be costly, as these are roaming animals with large space needs for their size, combined with the need to provide heat and ultraviolet light. Though the lizards bask at very high temperatures, there must be a temperature gradient within the enclosure allowing them to cool off away from the heat lamps. A cooling-down period over winter months can trigger the breeding response when temperatures rise in the spring. The temporary slowing-down of their metabolisms also lengthens the animals' lifespans.
Uromastyx are burrowing lizards, and need substrate deep enough to burrow in, or a low structure under which to hide. In the wild, these lizards' burrows can reach 10 feet in length.