Mary posing with a giant pillbug (Bathynomus giganteus).
It’s an isopod crustacean distantly related to the garden pillbugs.
Giant pillbugs live at 500 m or more in the Gulf of Mexico and scavenge on whatever they can find.
This is a big one but the record holder is at the U.S., Museum of Natural History (Smithsonian Institution) at about 16 inches (400 mm) long!