Legless lizard may refer to any of several groups of lizards that have independently lost limbs or reduced them to the point of being of no use in locomotion. It is the common name for the family Pygopodidae, but often refers to other groups, such as limbless anguids, depending on the region of the world. These lizards are often distinguishable from snakes on the basis of one or more of the following characteristics: possessing eyelids, possessing external ear openings, lack of broad belly scales, notched rather than forked tongue, having two more-or-less-equal lungs, and/or having a very long tail (while snakes have a long body and short tail).