One of the most common lizards found in the deserts of Mojave and Sonoran deserts in northwestern Mexico and the southwestern United States are the Desert Iguanas. They make an appearance on the different islands of Gulf of California as well. Desert Iguanas are easy to distinguish due to their gray and tan colors. These creatures tend to live from 8 to 10 years. They prefer to live in the wilderness and nearby rocky hillsides areas.