Glass lizards, or glass snakes, are a genus of reptiles that look like snakes. Although most species have no legs, their head shapes, movable eyelids, and external ear openings show they are lizards. A few species have very small, stub-like legs near their rear vent (cloaca). These are vestigial organs.
Like many lizards, they have the ability to drop off part of the tail when attacked. It can break into several pieces, like glass. The tail stays mobile, distracting the predator, while the lizard keeps still.