Bug Identifier
Horsehair worm
Community identification

Horsehair worm

Gordius robustus (and other species in the phylum Nematomorpha)

Order & Family
Gordioidea; Gordiidae
Size
Generally 4 inches to 14 inches (10 cm to 35 cm) long, but very thin (1-3 mm).
See this bug in the Encyclopedia

Natural Habitat

Freshwater environments like streams, ponds, puddles, or cisterns; larvae are internal parasites of insects.

Diet & Feeding

Larvae absorb nutrients from the body cavity of insect hosts (like crickets or beetles); adults do not feed.

Behavior Patterns

As larvae, they are endoparasites that can manipulate the behavior of their insect host to jump into water. They emerge from the host as adults to mate in aquatic environments.

Risks & Benefits

Harmless to humans, pets, and plants; they provide an ecosystem benefit by naturally controlling populations of crickets, cockroaches, and beetles.