Spiny Tailed Lizards
Uromastyx are large, heavy-bodied lizards of the genus, yep, you guessed it, Uromastyx. They are native to arid regions and are found from northwestern India, throughout southwestern Asia and the Arabian Peninsula to the Sahara of Africa. There are between 13 and 16 different species, but there are only four that we occasionally work with at Sandfire: Mali Uromastyx (Uromastyx maliensis), Egyptian Uromastyx (Uromastyx aegypticus), Banded Uromastyx (Uromastyx flavociata), and Saharan, sometimes referred to as Niger Uromastyx (Uromastyx geryi). Egyptian Uromastyx are the largest members of the genus, with adults reaching nearly three feet (76 cm). Most other species get to only about half that size or around 15” (35 cm). Mali Uromastyx are generally predominantly brown, grey or black, with some of the more colorful adult individuals displaying a mottled bright yellow on their backs. Egyptian Uromastyx are generally tan or grey, with varying patterns within these hues. Banded Uromastyx, are, of course, banded with black and white to yellowish bands. Saharan Uromastyx are often divided into yellow and red phases.
Uromastyx come from a large range, with one thing in common: Aridity. What this means is that they are accustomed to high, dry temperatures with little to no water availability. Due to the barren landscapes from which they come, Uromastyx spend a lot of time in the sun, and subsequently receive a lot of UV. In the wild they obtain most (if not all) of their water requirements from the foods that they eat.
If there is one key to the success of keeping Uromastyx, it would have to be a keen understanding of the desert climate. The deserts from which the Uromastyx genus originate are very hot and very dry. Uromastyx are thermophilic, that is, they require high temperatures to flourish. This one aspect is the most common mistake most hobbyists make with Uromastyx—not keeping them hot enough. Uromastyx require a basking site (surface) temperature of at least 110 degrees Fahrenheit, with 120 degrees being preferable. The most effective way to create this basking site is through the use of a full-spectrum UV spotlight of the type now commonly available at most pet stores, placed about twelve inches from the substrate of the enclosure. Wattage should be dictated by whatever creates a surface temperature of 120 degrees. Ideally, the bulb will heat an area equal to or slightly greater than the animal’s body mass. Placing a flat rock or piece of slate directly below the light can aid in raising the surface basking temperature, and an undertank heater can be used to supplement the bulb. The Uromastyx’s need for high temperatures cannot be stressed enough. Animals not kept hot enough will be lethargic, disinterested in food and more susceptible to stress and disease.
In addition to a proper basking location, a Uromastyx’s enclosure should provide a good thermal gradient, with the side opposite the basking spot having a decrease in temperature of 30-40 degrees (depending on the temperature of the basking spot). It is also a good idea to provide a hide spot (cactus wood, driftwood or commercially available sculpted décor can be used). Contrary to popular opinion, although Uromastyx come from deserts, they tend to avoid areas that are mostly sand, favoring areas that are more of a sand/soil mixture or some other clay or loam type blend (in which burrows are more easily made). Perhaps the best substrate to use is a premium (not dusty) wild bird seed which can easily be consumed by the Uromastyx. We have not had issues with keeping non-breeding animals on children’s play sand (other sands are too coarse or dusty), but there are also many digestible sand substrates on the market that some believe are superior. If aesthetics are not a concern, newspaper can also be used.
Uromastyx are omnivorous, but it is likely that in the wild the primary food source is vegetable matter (due to availability). Peas, corn, lentils, green beans, alfalfa or alfalfa pellets, collard, mustard and turnip greens, birdseed, dandelion greens, and other vegetable matter form a good basis for a Uromastyx diet. Most will also accept crickets, superworms, mealworms and wax worms, but insect offerings should be regularly interspersed with vegetable matter to discourage preferential eating. Provided that adequate vegetable matter is consumed, Uromastyx do not require supplemental water. That being said, many hobbyists feel more comfortable with a water dish in the enclosure even though we have never seen a Uromastyx drink from one. If you decide to provide a water dish, be sure it cannot be easily tipped over and remove it periodically as aridity should be maintained.
The most common problem with Uromastyx is temperature. If not provided with an adequate basking spot with a surface temperature of 110-120 degrees Fahrenheit, Uromastyx will not eat. At sub-ideal temperatures, they may eat but will not be able to properly digest their food. Equally important is the provision for a thermal gradient within the enclosure. Although Uromastyx are thermophilic, no animal wants to be hot all the time. Be sure to provide your animals with a 15-20 degree cooler location opposite their basking location. Hide spots are particularly important to minimize stress.