Amphisbaenidae Temporal range: Late Cretaceous–present, | |
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Amphisbaena alba | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Clade: | Amphisbaenia |
Family: | Amphisbaenidae Gray, 1865 |
Genera | |
12 extant, see text |
The Amphisbaenidae (common name: worm lizards) are a family of amphisbaenians, a group of limbless vertebrates.
Amphisbaenids occur in South America, some Caribbean islands, Europe, and sub-Saharan Africa.
One deep-branching and somewhat aberrant genus, Blanus , is native to Europe, and may represent a distinct family. [1] More recent sources indeed place it in the family Blanidae. [2]
Members of the family Amphisbaenidae are limbless, burrowing reptiles with carnivorous 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. [1] 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, it is an example of convergent evolution to the burrowing mammalian family Chrysochloridae (golden moles), in which the malleus in the middle ear is greatly enlarged. [3] [4]
Over 170 extant species are in the family, grouped into 12 genera:
A number of extinct taxa are known from the fossil record: [6]
Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They comprise the family Chrysochloridae and as such they are taxonomically distinct from the true moles, family Talpidae, and other mole-like families, all of which, to various degrees, they resemble as a result of evolutionary convergence. There are 21 species. Some are relatively common, whereas others are rare and endangered.
Amphisbaenia is a group of typically legless lizards, comprising over 200 extant species. Amphisbaenians are characterized by their long bodies, the reduction or loss of the limbs, and rudimentary eyes. As many species have a pink body and scales arranged in rings, they have a superficial resemblance to earthworms. While the genus Bipes retains forelimbs, all other genera are limbless. Phylogenetic studies suggest that they are nested within Lacertoidea, closely related to the lizard family Lacertidae. Amphisbaenians are widely distributed, occurring in North America, Europe, Africa, South America, Western Asia and the Caribbean. Most species are less than 6 inches (15 cm) long.
Bipes is a genus of amphisbaenians found only in Mexico, the sole living member of the family Bipedidae. They are carnivorous, burrowing reptiles, but unlike other species of amphisbaenians, they possess two stubby forelimbs placed far forward on the body. They also retain an almost complete pectoral girdle. The shovel-like limbs are used to scrape away soil while burrowing, in a manner similar to a mole. Evidence for their occurrence in the United States is reviewed by Somma (1993).
Trogonophidae is a small family of amphisbaenians, containing six species in four genera.
The Iberian worm lizard, Mediterranean worm lizard, or European worm lizard is a species of reptile in the family Blanidae of the clade Amphisbaenia. The Iberian worm lizard is locally known as cobra-cega (Portuguese), culebrilla ciega (Spanish), and colobreta cega (Catalan), all meaning "blind snake". Recent studies into the mitochondrial and nuclear genomic data of 47 isolated B. cinereus populations show rather large sequence divergence between two apparent clades, leading some researchers to call for a division of the Iberian worm lizard into two species. While little is known of B. cinereus in comparison with some other reptile species, new insight is growing about this primitive, ancestral reptile.
Blanus, also known as worm lizards, are a genus of amphisbaenians found in the Mediterranean region of Europe and North Africa. Like other amphisbaenians, Blanus species are specialized for a subterranean existence, with long, slender bodies, reduced limbs, and rudimentary eyes. Their skulls are powerfully constructed, allowing them to push through soil to create a burrow. Their jaws are well-developed, with large, recurved teeth and a pair of canine-like teeth in the upper jaw.
Darwin's ringed worm lizard is a species of amphisbaenian in the family Amphisbaenidae. It is endemic to South America.
Vanzolini's worm lizard is a species of amphisbaenian in the family Amphisbaenidae. The species is native to northern South America.
Amphisbaena ridleyi, known by the common names Ridley's worm lizard or the Noronha worm lizard, is a species of amphisbaenian in the family Amphisbaenidae. The species is endemic to the island of Fernando de Noronha off the coast of Brazil. It is one of two indigenous reptiles on the island.
Amphisbaena mertensii, also known as the Mertens' worm lizard or Mertens's worm lizard, is a species of worm lizard in the family Amphisbaenidae. The species is endemic to South America.
Leposternon microcephalum, also known commonly as the smallhead worm lizard, is a species of amphisbaenian in the family Amphisbaenidae in the reptilian order Squamata. The species is endemic to South America.
Dalophia is a genus of amphisbaenians in the family Amphisbaenidae, commonly known as worm lizards. Seven species are placed in this genus, all of them endemic to Africa.
Leposternon is a genus of amphisbaenians in the family Amphisbaenidae. Species in the genus are commonly known as worm lizards. 11 species are placed in this genus.
Loveridgea is a genus of amphisbaenians in the family Amphisbaenidae. Species in the genus are commonly known as worm lizards, even though they are not lizards. Two species are placed in this genus.
The Cuban many-ringed amphisbaena, also known commonly as the Cuban many-ringed worm lizard, is a species of amphisbaenian in the family Amphisbaenidae. The species is endemic to Cuba.
Slevin's worm lizard is a species of amphisbaenian in the family Amphisbaenidae. The species is endemic to northern South America.
Stejneger's worm lizard is a species of amphisbaenian in the family Amphisbaenidae. The species is endemic to Guyana.
Leposternon kisteumacheri is a species of amphisbaenian in the family Amphisbaenidae. The species is endemic to Brazil.
Monopeltis capensis, also known commonly as the Cape spade-snouted worm lizard, the Cape wedge-snouted worm lizard, the Cape worm lizard, and the South African shield-snouted amphisbaenian, is a species of amphisbaenian in the family Amphisbaenidae. The species is native to southern Africa.
Monopeltis sphenorhynchus, also known commonly as Maurice's slender worm lizard, Maurice's spade-snouted worm lizard, and the slender spade-snouted worm lizard, is a species of amphisbaenian in the family Amphisbaenidae. The species is native to southern Africa. There are two recognized subspecies.