The Guatemalan beaded lizard (Heloderma charlesbogerti), also called the Motagua Valley beaded lizard, is a highly endangered species of beaded lizard, a venomous lizard endemic to the dry forests of the Motagua Valley in southeastern Guatemala, an ecoregion known as the Motagua Valley thornscrub. It is the only allopatric species, separated from the nearest population of beaded lizards (H. alvarezi) by 250 km of unsuitable habitat. The Guatemalan beaded lizard is the rarest and most endangered species of beaded lizard and it is believed that fewer than 200 of these animals exist in the wild, making it one of the most endangered lizards in the world. In 2007, it was transferred from Appendix II to Appendix I of CITES due to its critical conservation status.