Lizard

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See Lizard in Wikipedia, the free encyclopedia.

Lizards are any (usually) limbed reptiles of the Order Squamata, and are considered separate from the snakes, and amphisbaenias by being placed within the Suborder Lacertilia. Lizards are distinguished from snakes by details of their jaw structure, but are more easily identified by usually having four functional legs, as well as functioning eyes with eyelids, and exposed ear-holes. However, not all lizards have all of these mentioned features, as some groups having lost some, such as geckos having eyes covered by a transparent eye-scale, earless lizards (obviously) having no external ear openings, or some species of skinks, along with all glass and snake lizards having no functional legs.

Lizards are among the most successful of all living, non-dinosaurian reptiles, with over 2,000 living species (approximately half of which are skinks) being present in almost all terrestrial environments, save tundras and high mountain tops.

Most experts consider the extinct Mosasaurs to be lizards, seeing them as being descendants of the monitor lizards, while other experts group them with the snakes within "Pythonomorpha."

With the revelation that the venom of venomous snakes had evolved long before the rise of snakes, some herpetologists believe that the iguanian (iguanas, anoles and relatives) and varanoid (monitor and earless lizards, gila monsters) lizards should be classified together with snakes and mosasaurs in a single "venom clade," Toxicofera. This page is a stub. You can help EvoWiki by expanding it into a full article. See this page for some ideas for how the page could look.