BATON ROUGE, La. (WGMB) – There’s a pest that is harmless to plants, but potentially harmful to humans and animals — and it’s in many states that enjoy warmer weather.

Native to Southeast Asia, hammerhead worms have an affinity for hot, humid locations. In the U.S., they are known to thrive in Alabama, California, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina and Texas, according to the Texas Invasive Species Institute’s (TISI) website.

They can also be found in greenhouses or places with “hot, humid environments,” the TISI says.

So where did hammerhead worms come from, and how did they end up in the U.S.?

Assistant Professor Nathan P. Lord, Ph.D. at Louisiana State University, said the worms may have made their way to the States is in the soil of ornamental plants. These worms hitchhiked to the USA and now can be found across areas that mimic their native climate.

They can also be a bit dangerous.

For starters, earthworms should be on alert because hammerhead worms consider them prey. But humans and pets should be wary, too.

“They actually produce a pretty nasty neurotoxin for paralyzing the earthworm prey, so there is certainly the potential for people and pets to be harmed if eaten or touched,” said Lord.

Those who spot hammerhead worms, or otherwise come into contact with one, are advised to put on a pair of gloves, refrain from touching them with bare skin, and, of course, avoid eating them. The TISI says anyone who handles a hammerhead flatworm should wash their hands with hot soapy water, rinse in alcohol and/or use hand disinfectant.

If you see one of these worms and have the urge to kill it, take a moment and consider your options: According to the TISI, you shouldn’t try to chop up the hammerhead worms, as this will only result in more hammerhead worms.

“Reproduction seems to be primarily achieved through fragmentation: a small rear portion of the worm will pinch off, and ‘stay behind’ as the worm moves forward,” the TISI writes.

“Within about 10 days, the head begins to form and this may happen a few times a month.”

Lord explained that “specialized cells” allow the worms to regenerate parts of their bodies, or “sometimes even entire new bodies from a small piece of the original worm.”

Both Lord and Dr. Blake Layton, of Mississippi State University, recommend putting salt on the hammerhead worms. The worms may also dry out if left in the bright sun for a period of time.

If all else fails, “squishing them is likely to do enough damage to kill them,” Lord said.