Within 24 hours of hatching, the worm is thought to form a protective covering or cyst. The life of the microscopic larvae is not completely understood. Depending on water temperature, the eggs hatch in 2 weeks to 3 months. Life CycleĪdults mate in water and females lay long gelatinous strings of eggs. They are not parasites of humans, livestock, or pets and pose no public health threat. When mature, they leave the host to lay eggs. Horsehair worms develop as parasites in the bodies of grasshoppers, crickets, cockroaches, and some beetles. These harmless, curious creatures writhe slowly, contorting their hair-like bodies into intricate knots. They are found in water or wet areas, such as in or alongside streams or puddles but they can occur in cisterns, livestock watering troughs or most open outdoor container with water. They are similar to nematodes but much longer (4 inches or longer) and very thin (1/80 to 1/10 inch diameter).

Horsehair worms, also known as Gordian worms, belong to the group Nematomorpha. University of Kentucky College of Agriculture ENTFACT-613: Horsehair Worms | Download PDF by Lee Townsend, Extension Entomologist

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