Nematomorpha

Phylum of parasitoid animals; horsehair worms

Nematomorpha (sometimes called Gordiacea, and commonly known as horsehair worms, hairsnakes, or Gordian worms) are a phylum of parasitoid animals similar to yet distinct from nematode worms in morphology, hence the name. Most species range in size from 5 to 10 centimetres (2 to 4 in), reaching 2 metres (6 ft 7 in) in extreme cases, and 1 to 3 millimetres (0.039 to 0.118 in) in diameter. Horsehair worms can be discovered in damp areas, such as watering troughs, swimming pools, streams, puddles, and cisterns.

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