Old World lizards

Lacertids are the typical lizards to many people. The name "lacerta" is Latin for "lizard" and includes a strictly Old World assembly of rather similar genera. All lacertids have four limbs and five clawed digits. The head and chin are covered with large symmetrical shields and the body is covered in fine round scales. Belly scales are rectangular or square and arranged in regular rows. The tail is longer than the combined head-body length, breaks off easily and generally may be regrown (=autotomy). Most species lay eggs, but several, including those from cold climates, produce live young. The viviparous lizard (Lacerta vivipara) is a widely-distributed species that enters the Arctic Circle, giving it the most northerly distribution among living lizards.

Lacertids are very similar to New World teiids, but no lacertid has a long forked tongue or grows in excess of 0.8 meters/28 inches. The upper temporal fossa is closed or greatly reduced. The teeth have hollow bases. Some species have osteoderms on the head. They have successfully invaded most habitats within their range, from tundra to desert. Despite this ecological variation, lacertids do not display an equivalent amount of anatomical variation. They lack crests and frills, but may vary considerably in color and pattern. Toes may be long and fringed in desert genera or short and cylindrical in grasslands species.

A desert lacertid (genus Acanthodactylus) from the Middle East.