Girdle Wearers: Loricifera

Girdle wearers attach themselves to sand or mud with a kind of glue made by glands located toward the rear of adults and on the toes of larvae. Larvae (LAR-vee) are animals in an early stage that change form before becoming adults. Adults crawl by using their spines and their mouth cones. The mouth cone telescopes out to its full length, fastens itself to a sand grain, and then draws in again so that the animal's body is pulled forward. The larvae use spines and bristles to crawl between grains of sand. They can also swim by using their toes. Girdle wearers eat by piercing bacteria and algae with their mouth spears and sucking out the contents.

Girdle wearers have separate sexes. Fertilization (FUR-teh-lih-ZAY-shun), or the joining of egg and sperm to start development, takes place either inside or outside the body. The primary larvae hatch from the fertilized (FUR-teh-lyzed) eggs and grow by shedding their outer layer. After two to five of these shedding stages, the larvae go into a resting stage and never feed. A male or female with fully developed reproductive organs emerges from the resting stage, and the life cycle repeats itself.

Some girdle wearers also have a cycle in which the larvae develop from eggs without fertilization. These larvae develop either into new larvae that develop without fertilization or into resting-stage larvae that shed their outer layer and transform into adult males or females.