Hairworms, also known as Gordian worms or horsehair worms, belong to the phylum Nematomorpha and are parasitic worms that develop in the bodies of insects such as grasshoppers, crickets, cockroaches, and some beetles
. They are long, thin, and brown to blackish in color, and they can be found in water or wet areas like streams, puddles, and ponds
. Adult worms are free-living in aquatic freshwater or marine environments, while the larvae are parasitic, often killing their hosts to complete their life cycle
. Horsehair worms are known for their ability to alter the behavior of their hosts, causing them to drown themselves
. The life cycle of these worms involves the following stages:
- Eggs : Adult worms lay long, gelatinous strings of eggs in water or on nearby vegetation, depending on the species
- Larvae : When the eggs hatch, the larvae can encyst to survive until they are ingested by a suitable host
- Parasitic stage : In some cases, the host directly ingests the larvae, which immediately move into their parasitic stage and develop within the host
. In other cases, the larvae of water-inhabiting insects or tadpoles ingest the preparasitic larvae
- Adult worms : Adult horsehair worms are free-living in aquatic freshwater or marine environments
Horsehair worms are not a threat to humans, livestock, or pets, and they do not pose any public health risk
. They are commonly encountered in agricultural areas, particularly those with water-impoundment and irrigation facilities
