| Nematomorpha are known as Horsehair worms or Gordian worms. They are extremely slender worms, reaching lengths up to 1 meter, while being only a few mm in diameter. As adults they are free living in fresh water (with a few exceptions). Larvae develop inside various insects, such as cockroaches and grasshoppers. Once the horsehair worm is mature, it changes the behavior of the hosts, making it more likely that the host will enter the water. Here the worm exits its host, which then dies. Mating takes place in the water and the female lays the eggs in gelatinous strings. Obviously, to infect a terrestrial host the emerging larva needs to leave the water. They can accomplish this via the so-called paratenic or transport host. In some nematomorph species, the larvae make the transition from water to land by forming cysts in aquatic insect larvae. These cysts survive the host's metamorphosis to an adult, which can then transport the cysts to the land. |
