The veiled chameleon, Chamaeleo calyptratus, is a large species of chameleon found in the mountain regions of Yemen, United Arab Emirates and Saudi Arabia. It is also sometimes referred to as the Yemen Chameleon. The male veiled chameleon is green in color and, depending on the animal's emotional state, this green will range from a bright lime green to a red olive drab. Surroundings only partly contribute to a chameleon's "decision" to change color.