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iconHave you seen a cockroach worm before?

“I’ve got a German cockroach with a long worm coming out of it.  Can you tell me what it is?” asked Mary, one of our valued customers.

horsehair worms Horsehair worms have been around for about 500 million years.  They are similar to nematodes and are most commonly found amongst the vegetation near edges of water or wet areas.  They are very thin, max about 3mm, but may grow as long as 1m.horsehair

Horsehair worm eggs hatch in water and the larvae form a protective covering.  When eaten by a suitable insect (eg grasshopper, cricket, beetle, dragonfly, millipede or in this case a cockroach) the protective covering dissolves and the larva bores through the gut wall and into the body of the host.  When mature, they leave the host to seek a mate.

Horsehair worms move with a slow whipping action but their most distinctive habit is to wrap themselves into knots – hence the alternative name Gordian worm.  They are not harmful to man, livestock, pets or plants but their presence indicates the activity of invertebrates in the area.

Named after Gordian Knot.