Mexican beaded lizard debate among scientists. However, this venom has been found to contain several enzymes useful for manufacturing drugs in the treatment of diabetes, and research on the pharmacological use of its venom is ongoing. Threatened throughout its range by overcollection and habitat loss, it is a CITES protected species. The Guatemalan beaded lizard ("H. charlesbogerti" ) is one of the rarest lizards in the world, with a wild population of fewer than 200. The beaded lizards have one close living relative, the Gila monster ("H. suspectum"), as well as many extinct relatives in the Helodermatidae, whose genetic history may be traced
Common collared lizard Collared lizards in the wild have been the subject of a number of studies of sexual selection. In captivity if two males are placed in the same cage they will fight to the death. Males have a blue-green body with a light brown head. Females have a light brown head and body. Two black stripes around the neck give these lizards their name. Common collared lizard The common collared lizard ("Crotaphytus collaris"), also called eastern collared lizard, Oklahoma collared lizard or collared lizard, is a North American lizard that can reach in length (including the tail), with a large head