Chuckwalla
(Soromalus obesus)
These impressive animals were most often seen only in certain parts of the Irwin Military Installation. Most often on large boulder out crops. When frightened these larger lizards dive into boulder crevices and inflate their bodies. They are so inflated in fact that trying to remove them without harming the animal is almost impossible unless you get lucky and the go into the crevice or crack of smaller rocks unknowingly.