When people express fears about sea creatures, it’s usually sharks or jellyfish.

The Harte Research Institute for Gulf of Mexico Studies at Texas A&M University-Corpus Christi unlocked a new beach fear this month, fireworms.

“Your worst nightmares are washing up right now in the form of fireworms!” a Facebook post from the Harte Research Institute for Gulf of Mexico Studies said.

Texas A&M researchers said a few painful worms were found recently on Mustang Island and Padre Island. The fireworms were found on logs with barnacles, which the fireworms may have been feeding on.

The worms are “rare to find unless you know where to look,” researchers said in a comment.

Fireworms, also called bearded fireworms, are bright-colored marine bristle worms found in almost all parts of the ocean, according to the Ocean Conservancy.

How painful is a fireworm?

A sting from one could leave you in severe pain with a "fire-like" sensation for up to three hours, and a scar for several weeks.

And if they don’t already sound terrifying enough, Tunnell said the worms can produce asexually, if you cut one in half, it will regenerate into two worms. And they can live for up to nine years!

There are more than two dozen species of fireworms around the world. The bearded fireworm is the species written about the most.

The one Tunnell found this month was the Amphinome rostrata.

Tunnell said if you get stung, you should put duct tape on your skin over the sting area and then quickly rip it off to remove the spines. Even then, expect the pain to linger.

“You could use vinegar and warm water to see if that helps,” he said, adding that it’s going to be painful “no matter what.”