Exo Terra Cholla Skeleton Exo Terra Cholla Skeleton – The cholla cactus is native to the Southwestern United States and Northern Mexico – the Sonoran Desert. A tree-like plant with one low-branching trunk that grows to heights of 4 m or 12 ft. They grow in thick bushes which form the perfect hide-out for many reptile species. Many species live in these bushes and seek refuge when threatened by predators, or simply to escape from the hot desert sun. Especially the skeleton is a great hiding spot for many reptiles, amphibians and invertebrates!