Lizard heads called the parietal eye, a basal ("primitive") feature also present in the tuatara. This "eye" has only a rudimentary retina and lens and cannot form images, but is sensitive to changes in light and dark and can detect movement. This helps them detect predators stalking it from above. Until 2006 it was thought that among lizards, only the Gila monster and the Mexican beaded lizard were venomous. However, several species of monitor lizards, including the Komodo dragon, produce powerful venom in their oral glands. Lace monitor venom, for instance, causes swift loss of consciousness and extensive bleeding through its
Bocage's wall lizard Bocage's wall lizard Bocage's wall lizard ("Podarcis bocagei") is a species of lizard in the family Lacertidae. The species is endemic to the Iberian Peninsula. Its natural habitats are temperate forests, temperate shrubland, Mediterranean-type shrubby vegetation, sandy shores, rural gardens, and urban areas. The IUCN does not consider it to be threatened. Both the specific name, "bocagei", and the common name, Bocage's wall lizard, are in honor of Portuguese zoologist José Vicente Barbosa du Bocage. Bocage's wall lizard grows to a snout-to-vent length of about , with a tail twice as long as this, males being larger than females. It