Tailless Caecilians: Caeciliidae

Little is known about the behavior of land-dwelling tailless caecilians because of their secretive, soil-dwelling nature. Some of these animals emerge from deep in the soil or leaf litter to look for food at dusk or dawn, often during light rain. Tailless caecilians are expert burrowers, digging head-first through moist soil that is rich in decayed plant matter. Species may differ in their ability to burrow efficiently in different kinds of soils. Tailless caecilians appear to spend most of their time in their burrows, but they also can travel quite far from their burrows. Scientists know little about the behavior of the water-dwelling and partially water-dwelling tailless caecilians because these animals typically live in slow-moving streams and rivers that have a lot of plant material that obstructs the view of the animals.

At mating time a male tailless caecilian inserts sperm directly into the female's reproductive tract. Scientists have observed tailless caecilians in aquariums coiling around each other before the male places the sperm in the female. The eggs are fertilized (FUR-teh-lyzed), or joined with sperm, inside the female's body.

Tailless caecilians use several methods of reproduction. Some species lay eggs that hatch into free-living larvae. Larvae (LAR-vee) are animals in an early stage that change body form in a process called metamorphosis (MEH-tuh-MORE-feh-sis) before becoming adults. Some species lay eggs on land, and the larvae develop and go through metamorphosis before hatching, so that when they hatch they have the body form of adults. In some species the young develop in the egg ducts of the female, eating nutrient liquid made by the egg ducts. These young also are born with the body form of small adults. The females of some species of tailless caecilians take care of their eggs by coiling their bodies around the cluster of eggs. They also take care of newly hatched young.