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,
Cope's arboreal alligator lizard Cope's arboreal alligator lizard Cope's arboreal alligator lizard ("Abronia aurita") is a species of lizard found in two isolated locations in Guatemala, one in the Alta Verapaz Department and one in the Jalapa Department. These lizard are found only in high altitudes of 2,000 to 2,600 feet above sea level, on the west and south sides of the mountain ranges. This lizard is one of 28 species of alligator lizards, most being arboreal, meaning they live in trees. These omnivores are considered endangered because of their small population size and they face extinction due to habitat degradation and from pressures