Mexican Beaded Lizard

Mexican Beaded  lizard shares many characteristics with its close relative, the more famous Gila monster. These are the only two surviving members of an ancient group of lizards—and the world’s only dangerously venomous lizards. Unlike venomous snakes, which have specially adapted fangs to inject venom, these lizards use a chewing motion to work the venom that flows from grooves in their teeth into their victim. This requires the lizard to hold onto the victim to maximize the amount of venom in the wound. Beaded lizards have a very strong bite. Once their jaws fasten onto a predator, it is difficult to break the hold. Venom is used mainly as a defense. Before biting, the lizard will back away, display an intimidating warning gape, and hiss. Predators include coyotes and birds of prey. Mexican beaded lizards rarely bite humans and generally do so only when they feel threatened.

Mexican beaded lizards make their homes in abandoned mammal burrows, under rocks, or in tunnels they dig. They may spend 95 percent of their time underground. Active primarily at dusk and after dark, they use their forked tongues and sensory cells in their noses to locate prey. Beaded lizards play a crucial role in ecology by helping to control the population of rodents, insects, and other desert animals.