Gila Monster Lizard (Heloderma suspectum)

Heloderma suspectum, commonly known as the Gila monster, is one of only a few known venomous lizards in the world. Native to the arid deserts and scrublands of the southwestern United States and northwestern Mexico, this slow-moving but highly specialised reptile is easily recognised by its stout body, bead-like scales (osteoderms), and striking black-and-orange or pink coloration—a warning of its toxicity.

Unlike snakes, the Gila monster delivers venom through grooves in its lower teeth, using a chewing motion to inject it into prey or a threat. Though rarely dangerous to humans due to its reclusive nature and sluggish speed, its venom is potent and has been studied for medical applications, including the development of drugs to treat type 2 diabetes (e.g. exenatide).

Gila monsters are crepuscular and fossorial, spending much of their time in burrows to avoid the desert heat. They feed infrequently, consuming bird eggs, small mammals, lizards, and carrion, storing fat in their tails for long periods of dormancy.