Mexican beaded lizard generic name "Heloderma" means "studded skin", from the Ancient Greek words "hêlos" (ἧλος)—the head of a nail or stud—and "dérma" (δέρμα), meaning skin. Its specific name, "horrĭdum", is the Latin word meaning rough or rude. The four subspecies of beaded lizard, elevated to full species in 2013, are: Adult beaded lizards range from in length. They are substantially larger than the Gila monster, which only reaches lengths of . The snout-to-vent length of a beaded lizard averages . The average body mass of an adult beaded lizard is , about 45% heavier than the average mass of a gila monster,
Mexican mole lizard this burrowing species only surfaces at night or after heavy rain. It uses its autotomous tail as an escape tatic for predators. Losing a part of the tail while burrowing can plug up the hole behind it, giving it time to escape from any kind of predator that might be chasing it down. It is an opportunist carnivore and eats ants, termites, ground-dwelling insects, larvae, earthworms, and small animals including lizards. It usually pulls its prey under ground to start its meal. Mexican mole lizard The Mexican mole lizard (Bipes biporus), commonly known as the five-toed worm lizard, or simply