“Hammerhead worms found in the United States are not native to North America,” Dellinger said. “It’s okay to kill any that you find around your home as these species are considered invasive.

Researchers have spotted the hammerhead worm hundreds of times in the area of Washington, D.C. and northern Virginia over the last 15 years, the Washington Post reported. While a human would have ...

There are similarities in their toxin to that of the pufferfish, a tetrodotoxin, but there is little known about how this toxin affects the environment where hammerhead worms are found.