Bipedidae is a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

amphisbaenia Amphisbaenia (called amphisbaenians or worm lizards) 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. A ...

ns that includes the extant

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

'' Bipes'' represented by three

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

from

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

and the southern coast of

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

and the extinct genus '' Anniealexandria'' represented by one species that lived in what is now

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

during the earliest Eocene around 55 million years ago. Phylogenetic analysis indicates that Bipedidae is most closely related to the family Blanidae, which includes the living genus '' Blanus''. Bipedidae are very small, usually ranging from 120 to 240 mm. They lack external hind limbs and are the only amphisbaenians with well-developed fossorial front limbs, which each include five claws. They have a short tail that does not regenerate if lost. They use their blunt head for burrowing by ramming it into the soil, and usually prey on arthropods.

References

Amphisbaenians Lizard families Taxa named by Edward Harrison Taylor Extant Eocene first appearances {{lizard-stub