A 37 cm long Gordian Worm and the katydid it emerged from.
Image: Alan Henderson
Source: Museum Victoria
Question: I saw a Praying mantis land in a swimming pool. It got out and then a massive parasitic worm, more than twice the Mantis’s length came out of its anus. Do they normally have a parasite inside?
Answer: This is a classic example of a Gordian Worm – a common, but rarely noticed, parasite of invertebrates. Part of the worm’s life cycle is within water. The host, near the end of its life (in this case a mantis) is somehow driven to water by its internal demon, and the worm is free to make its way out to complete the cycle. Further information about Gordian Worms and their lifecycles can be found in the links at right.