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The worm lizard Bipes biporus is an amphisbaenian, a type of elongate burrowing reptile that is often pink and wormlike in appearance. Bipes is the only amphisbaenian genus with limbs; in particular, members of this genus have small but well developed forelimbs. This genus is also the only squamate taxon in which the forelimbs are better developed than the hind limbs. As a species, B. biporus always has five digits on each limb, its head is blunt, and it burrows in sandy desert soils on the peninsula of Baja, California. Its tail is short and autotomic, although once it is lost it will not regenerate. This species exhibits no external sexual dimorphism. Like other amphisbaenians, its skin is marked with ringlike annuli, contributing to its wormlike appearance.
Bipes biporus is a generalist predator that preys primarily on invertebrates, especially arthropods. This species lives in self-constructed tunnels in the soil and, although it typically resides close to the surface, it rarely emerges from underground. As a result, its most likely predators are snakes, which are well suited to enter and navigate its underground burrow systems. Bipes biporus is active year-round, due in part to its capacity for behavioral thermoregulation. This species moves primarily by lateral undulation and concertina locomotion, techniques common among fully limbless reptiles, although it may use its forelimbs to assist in locomotion. Reproduction in this species is oviparous and biennial, with females laying small clutches of one to four eggs every other year.