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
Transvaal grass lizard on slopes and ridges. This lizard is ovoviviparous, meaning mothers carry eggs inside their bodies until they are ready to hatch. Neither the Southern African Red Data nor the International Red Data list the Transvaal grass lizard. However, the Swaziland Red Data puts the lizard at Near Threatened levels. The scientific name of this lizard, Chamaesaura aenea, is due to the lizard's copper color. Aenea is a Latin word meaning "bronze" or "copper." Transvaal grass lizard The Transvaal grass lizard, also known as the Coppery grass lizard and Transvaal snake lizard, is a species of lizard in the genus Chamaesaura.