DESTIN — Little blue creatures resembling jellyfish have begun to wash up on local beaches, but officials say it’s not exactly a marine alien invasion.

Blue buttons, as they’re called, are commonly thought to be jellyfish but actually are a tiny colony of hydroids, small predatory creatures distantly related to jellyfish. According to the National Oceanic and Atmospheric Administration, Porpita porpita are most commonly found in saltwater environments.

Graham Northup, curator of fish and reptiles at the Gulfarium Marine Adventure Park, said the blue “button” in the center actually is filled with gas and acts as the home base to the series of hydrozoans, the creatures resembling tentacles that are attached to the button.

“The gaseous structure allows them to float, similar to a man-o-war jellyfish,” Northup said. “They float on the surface and they’re drifters, and they kind of go with the wind and the currents and wherever the Gulf takes them, which is why they sometimes end up on the beach together.”

The blue buttons don’t sting quite in the same way as jellyfish, but do have stinging cells that can cause skin irritation, Northup said. It’s best to avoid them if you see them on the beach.

A smattering of blue buttons could be seen by The Back Porch restaurant and Henderson Beach State Park in Destin Thursday morning. The bright blue creatures, about the size of a quarter, stand out on the white sand.

Joe D’Agostino, beach safety chief with the Destin Fire Control District, said he had heard some reports of blue buttons washing up the past few days, but they didn’t show up in numbers large enough to warrant concern from lifeguards.

“We haven’t seen them in any mass numbers where it would be a problem for the general public,” D’Agostino said. “We haven’t seen anything that would warrant us flying purple flags (indicating the presence of marine pests).”

Portuguese man-o-war and “by-the-wind sailor” jellies are more commonly known to wash up on local beaches, but neither have been reported in mass quantities so far this season.