Hair Worms: Nematomorpha

Physical characteristics: The color of Paragordius varius worms ranges from light yellow to nearly black. These worms are 4 to 14 inches (100 to 350 millimeters) long and about 0.03 inch (700 micrometers) wide. The tip of the male's tail is split in two and the tip of the female's tail in three.

Adult Paragordius varius worms live in and near slower streams, puddles, and places where rainwater collects. (Illustration by Bruce Worden. Reproduced by permission.)

Geographic range: Paragordius varius (abbreviated as P. varius) worms live in North and South America.

Habitat: Adult P. varius worms live in and near slower streams, puddles, and places where rain water collects. The larvae live in crickets and grasshoppers.

Diet: P. varius larvae absorb nutrients from their hosts. The adults do not eat.

Behavior and reproduction: In the spring, water insects carrying P. varius larvae transform into flying adults. Crickets and grasshoppers are infected when they eat dead insects containing worm larvae. Development to adult worms inside the host takes about one month. With this fast development, as many as three generations are produced in a single year.

Paragordius varius and people: P. varius worms do not infect humans.

Conservation status: P. varius worms are not considered threatened or endangered. ∎