Five-toed worm lizard
The Mexican mole lizard (Bipes biporus), also commonly known as the Five-toed worm lizard, or simply as Bipes, is a species of amphisbaenian in the family Bipedidae. The species is endemic to the Baja California Peninsula. It is one of four species of amphisbaenians that have legs.
B. biporus is pink and worm-like, 18–24 cm (7.1–9.4 in) in snout-to-vent length (SVL) and 6–7 mm (0.24–0.28 in) in width. It lives for one to two years. Its skin is closely segmented to give a corrugated appearance, and like earthworms, its underground movement is by peristalsis of the segments. Its blunt head allows it to burrow into sandy soils efficiently. The forelegs are strong and paddle-like, while the hind legs have disappeared, leaving behind only vestigial bones visible in X-rays. The tail is autotomous without any regeneration. Due to sacrificing the development of its ear to permit it to dig more efficiently, the Mexican mole lizard has evolved to have its skin transmit vibrations to the cochlea.
Mexican mole lizards are found in Baja California, Baja California Sur, Guerrero, and Chiapas, in Mexico. In these areas, they inhabit sandy soils in desert with xeric shrub vegetation.
Mexican mole lizards are burrowing creatures that only surface at night or after heavy rain. They are generalist predators that feed on easily accessible prey found in soil, debris, and dirt. They spend time singly and interact with each other only during the breeding season. When feeling threatened, Mexican mole lizards use their autotomous tail as an escape tactic for predators. Losing a part of the tail while burrowing can plug the hole behind them, giving them time to escape.
Mexican mole lizards are carnivores and eat ants, termites, ground-dwelling insects, larvae, earthworms, and small animals including lizards.
Mexican mole lizards breed underground. They are oviparous, and the females lay 1 to 4 eggs in midsummer. The eggs hatch after 2 months.
Mexican mole lizards lead a secretive life underground and thus don’t face any major threats at present.
According to IUCN Red List, the Mexican mole lizard is abundant throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today remain stable.