Horsehair worm

Freshwater environments like streams, ponds, puddles, and water troughs; adults are aquatic, while larvae are parasitic in terrestrial hosts.

Larvae are internal parasites of arthropods (grasshoppers, crickets, beetles); adults do not eat as they lack a functional digestive tract.

They are known for their ability to manipulate the behavior of their insect hosts, compelling them to seek water so the adult worm can emerge and reproduce. Once in water, they form tight knots, leading to the name 'Gordian worms'.

Harmless to humans, livestock, and pets as they cannot parasitize vertebrates. They are beneficial for ecosystem health by naturally controlling populations of certain insects like crickets and grasshoppers.