Blindskinks: Dibamidae

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BLINDSKINKS: Dibamidae

PHYSICAL CHARACTERISTICS

Blindskinks (also called "blind lizards," "blind skinks," "legless lizards," and "wormlizards") are small to medium-sized lizards with a slim, snakelike form. They are fewer than 10 inches (25.4 centimeters) long. Their body colors range from pale pink to light brown, with the under area, or belly, sometimes a bit paler. Their bodies are covered with shiny, smooth, and squarish overlapping scales. The scales on the head are large and platelike, especially on the snout, or nose area, and lower jaws.

The heads of these reptiles are blunt, not pointed. The bones of the skull are fused, or firmly joined together. This makes the head area very solid, which helps in burrowing, or digging holes. Their tiny eyes look like dark specks and have no lids. The eyes are hidden under a head scale that does not move. The nostrils, or nose openings, are small and placed at the tip of the snout. These lizards have no ear openings that can be seen. Their ears are covered with scales. There are only a few lower teeth, set in sockets, or hollow openings. The teeth are small and pointed, curving backward. The tongue is short and wide and is not divided at the tip. The tip of the tongue does not retract, or pull back, completely.

The tails of blindskinks are very short and blunt. They are able to break off at various places to deter predators (PREH-duh-ters), or animals that hunt the blindskink for food. Blindskinks do not have any working limbs, or legs. Males have small, flaplike hind limbs, or back legs. These limbs may be used in mating. Females have no limbs or flaps. Pectoral (PECK-ter-uhl), or chest, bones are absent. The hip-bone area is very small. These features give the blindskink its slim shape.

GEOGRAPHIC RANGE

The majority of blindskink species are found in eastern India; southern Thailand; Borneo; Vietnam; Laos; Kampuchea; the Nicobar, Sunda, and Andaman Islands; southern China; Sumatra; Malaysia; most of Indonesia; the Philippines; and westernmost New Guinea. A single species is found in a very small area of northeastern Mexico.

HABITAT

Almost all blindskinks live in rainforests. Most species require damp humus (HYU-mus) or broken up, loose, rotting plant material. During the dry season these species of blindskink burrow beneath rocks or logs. The blindskink of northeastern Mexico has adapted to a wider type of living area. It is found in semiarid deciduous (di-SID-joo-wus) brushland and open scrubland, or areas with bushes and small trees that lose their leaves in dry or cold weather. This lizard also lives in desert areas, often near ant and termite nests. It also inhabits pine-oak forests. It has been found beneath rocks, in or under rotting logs, in loose litter, and in the decayed, or rotting, bases of yuccas, a treelike plant that grows in dry areas.

DIET

Blindskinks feed on tiny insects, such as ants and termites and possibly spiders.

WHO ARE THE RELATIVES?

Scientists are still trying to find out more about the blindskinks' evolution (eh-vuh-LU-shun), or the changes they have undergone to adapt to their environment over time. These are very unusual lizards, both in appearance and in living habits. Most species are known from fewer than 20 specimens, or examples. Over the years scientists have proposed that blindskinks are related closely to snakes; geckos; skinks; carnivorous (KAR-nih-vuh-rus), or meat-eating, anguid lizards; and worm lizards, which look like earthworms. There is still no definite answer.

BEHAVIOR AND REPRODUCTION

Very little is known about the living habits of blindskinks. They are secretive lizards, preferring to hide. Blindskinks live on the forest floor, often underneath stones, but sometimes underneath leaf litter or moving about underground. They enter the earth through cracks in the soil or by way of tunnels made by other animals. In soft, loose soils or rotting leaf litter their slim body shape and rigid head allow them to dig their own tunnels. Blindskinks may take up residence in tunnels made by other insects or in the underground homes made by insects that live in groups, such as termites.

Nothing is known of the mating or egg-laying habits of the blindskinks living in Mexico. Little is known of the mating habits of the rainforest species. It is believed that after mating, the females lay just one egg. An egg may be laid more than once a year. The eggs are soft and somewhat long. Later they become harder and shaped more like eggs.

BLINDSKINKS AND PEOPLE

Blindskinks do not interact with people. Few people ever see them.

CONSERVATION STATUS

Blindskinks are not threatened. Many species suffer from loss of their habitat, or their preferred living area, as the result of movements of people, farming, tree removal, and pollution, or poison, waste, or other material that makes the environment dirty and harmful to health. There are no conservation efforts under way to protect blindskinks.

FOR MORE INFORMATION

Books:

Arnosky, Jim. All about Lizards. New York: Scholastic, 2004.

Bartlett, Richard D. In Search of Reptiles and Amphibians. New York: E. J. Brill, 1988.

Cogger, Harold, and Richard Zweifel, eds. Reptiles and Amphibians. San Francisco: Weldon Owens, 1992.

Halliday, Tim, and Kraig Adler, eds. Encyclopedia of Reptiles and Amphibians. New York: Facts on File, 1986.

Lamar, William. The World's Most Spectacular Reptiles and Amphibians. Tampa, FL: World Publications, 1997.

Mattison, Chris. Lizards of the World. New York: Facts on File, 1989.

Pough, F. Harvey, Robin M. Andrews, John E. Cadle, Martha L. Crump, Alan H. Savitzky, and Kentwood D. Wells. Herpetology. Upper Saddle River, NJ: Prentice Hall, 1998.

Riccuiti, Edward R. Reptiles. Woodbridge, CT: Blackbirch Press, 1993.

Sprackland, Robert G., Jr. All about Lizards. Neptune City, NJ: T. F. H. Publications, 1977.