Horsehair Worm
Scientific Name: Gordius robustus (and other Chordodidae/Gordiidae species)
Order & Family: Order: Gordiida; Family: Gordiidae
Size: Typically 10 cm to 35 cm in length, with a very thin width of 1 mm to 3 mm.
Natural Habitat
Found in aquatic environments like puddles, streams, and troughs, or on damp ground after rain.
Diet & Feeding
As larvae, they are internal parasites of insects (like crickets and beetles); as adults, they do not eat.
Behavior Patterns
Parasitic larvae manipulate the host's behavior to seek water; adults emerge from the host into water to mate and lay eggs.
Risks & Benefits
Harmless to humans, pets, and plants; they help control populations of pest insects like crickets and cockroaches.
Identified on: 1/11/2026