Amphisbaenia
| Worm lizards Fossil range: Cretaceous - Recent | ||||||||||
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 black: range of Amphisbaenia |
The Amphisbaenia are a suborder of peculiar, usually legless squamates closely related to lizards and snakes, in spite of their resemblance to earthworms (many possessing a pink body color and scales arranged in rings). They are very poorly understood, due to their burrowing lifestyle and general rarity. Most species are found in Africa and South America, with a few in other parts of the world. Little is known of them outside of their anatomy, and even that is difficult to study due to the mechanics of dissecting something so small. Most species are less than 6 inches (150 mm) long.
The head is stout, not set off from the neck, and either rounded, sloped, or sloped with a ridge down the middle. Most of the skull is solid bone, and they have a distinctive single median tooth in the upper jaw. They have no outer ears, and the eyes are deeply recessed and covered with skin and scales. The body is elongated, and the tail truncates in a manner that vaguely resembles the head. Their name is derived from Amphisbaena, a mythical serpent with a head at each end. The three species of Mexican Mole Lizard, genus Bipes, are unusual in having a pair of forelimbs, but all limbless species have some remnants of the pelvic and pectoral girdles embedded within the body musculature.
The skin of amphisbaenians is only loosely attached to the body, and they move using an accordion-like motion, in which the skin moves and the body seemingly just drags along behind it. Uniquely, they are also able to perform this motion in reverse just as effectively.
Families
- Amphisbaenidae - Gray, 1865 -- Amphisbaenids, tropical worm lizards[1]
- Bipedidae - Taylor, 1951[2]
- Rhineuridae - Vanzolini, 1951 -- North American worm lizards[3]
- Trogonophidae - Gray, 1865 -- Palearctic worm lizards[4]
References
- Amphisbaenidae (TSN 209627). Integrated Taxonomic Information System. Retrieved on 19 August 2007.
- Bipedidae (TSN 564539). Integrated Taxonomic Information System. Retrieved on 19 August 2007.
- Rhineuridae (TSN 564535). Integrated Taxonomic Information System. Retrieved on 19 August 2007.
- Trogonophidae (TSN 209638). Integrated Taxonomic Information System. Retrieved on 19 August 2007.
Other references
- Wu X.-c., D. B. Brinkman, A. P. Russell, Z.-m. Dong, P. J. Currie, L.-h. Hou, & G.-h. Cui (1993). "Oldest known amphisbaenian from the Upper Cretaceous of Chinese Inner Mongolia." Nature 366: 57-59.
Source: adapted by the editor from Wikipedia, the free encyclopedia; from the article "Amphisbaenia". Image Credit.
