"Lichanura trivirgata Cope, 1868, is the only representative of the family Boidae on islands in the Gulf of California (Grismer, 2002). It is a medium length snake, with a blunt head, small eyes, and a short prehensile tail (Stebbins, 2003). Its current distribution spans the xeric regions around the Gulf of California, from southwestern California in the United States to the tip of the Baja California peninsula and southern Arizona to the vicinity of Guaymas in Sonora, Mexico. It is known to occur on nine islands, including Cedros and Santa Margarita islands in the Pacific Ocean and Angel de la Guarda, Mejia, Tiburon, Carmen, San Marcos, Espiritu Santo and Cerralvo islands in the Gulf of California (Grismer, 2002; Frick et al., 2016; Fig. 1). The species is on the Mexican list of endangered species (NOM-059) (SEMARNAT, 2010)."