The Amphisbaenidae (

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

: worm lizards) are a family of

amphisbaenian Amphisbaenia (called amphisbaenians or worm lizards) is a group of usually legless squamates, comprising over 200 extant species. Amphisbaenians are characterized by their long bodies, the reduction or loss of the limbs, and rudimentary eyes. As ...

s, a group of

limbless vertebrates Many vertebrates have evolved limbless, limb-reduced, or apodous forms. Reptiles have on a number of occasions evolved into limbless forms – snakes, amphisbaenia, and legless lizards (limb loss in lizards has evolved independently several ti ...

Geographic range

Amphisbaenids occur in South America, some

Caribbean The Caribbean (, ) ( es, El Caribe; french: la Caraïbe; ht, Karayib; nl, De Caraïben) is a region of the Americas that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Se ...

islands, Europe, and

sub-Saharan Africa Sub-Saharan Africa is, geographically, the area and regions of the continent of Africa that lies south of the Sahara. These include West Africa, East Africa, Central Africa, and Southern Africa. Geopolitically, in addition to the List of sov ...

Taxonomy

One deep-branching and somewhat aberrant genus, '' Blanus'', is native to Europe, and may represent a distinct family. More recent sources indeed place it in the family Blanidae.

Description

Members of the family Amphisbaenidae are limbless, burrowing

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...

s with

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

diets. As in other amphisbaenians, the body bears rings of scales, which gives amphisbaenids a worm-like appearance. The head is massively constructed and used for burrowing, with powerful jaws and large, recurved teeth used for seizing prey. Some species have a spade-like head, while others have a narrow keel on the head, and still others have a rounded skull. The eyes are highly reduced, while the ear bone, or stapes in the middle ear, is large and massive. Together with another bone, the extracollumella, the stapes detects vibrations caused by prey items, allowing amphisbaenids to hunt for invertebrates under ground. In this respect, apparently evolution exists convergent to the burrowing mammalian family Chrysochloridae, in which the malleus in the middle ear is greatly enlarged.

Extant genera

Soutpansberg Wormlizard (Chirindia langi subsp

Over 170 extant species are in the family, grouped into 12

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

Fossil genera

A number of extinct taxa are known from the fossil record:

References

External links

*http://www.jcvi.org/reptiles/families/amphisbaenidae.php {{Taxonbar, from=Q733407 Amphisbaenians Reptile families Taxa named by John Edward Gray Extant Maastrichtian first appearances