By Dawson Bailey
Howard County Extension Agent
A hammerhead worm was recently found in a residence in Howard County. Hammerhead worms are native to tropical and southeast Asia. They have become invasive worldwide and have been reported in Arkansas for at least a decade. Multiple species have been introduced into North America since at least 1901, but the data on their distribution is spotty. One species, the Shovel- Headed Garden Worm, has been observed in at least 10 counties in Arkansas.
The most visual characteristic of these worms is their broad, spade-shaped head. The Shovel- headed Garden Worm typically grows 8-12 inches. They are light-colored with 1-5 dark, thin dorsal stripes. These worms prey on insect larvae, slugs, snails, and various earthworm species. Hammerhead worms are also known to be cannibals.
Many species of hammerhead worms contain a neurotoxin called tetrodotoxin. They use this neurotoxin to immobilize their prey and defend themselves against predators. This toxin can
irritate your skin if handled and will sicken pets if eaten. As a precaution, DO NOT handle these worms without gloves.
If you find one of these worms, using gloves, place it in a container or plastic bag with salt and vinegar, then freeze it overnight before you dispose of it. Do not try to kill the worm by cutting or chopping it. They will reproduce by fragmentation, only making the problem worse.
For more information on Hammerhead worms, you can contact the Howard County Extension office at 870-845-7517 or find helpful fact sheets on our website at www.uada.edu. The Cooperative Extension Service is part of the University of Arkansas System Division of Agriculture.