LOOK: Mysterious, Football-Sized Creatures Found in Gulf of Mexico Roaming on Seafloor

by Sean Griffin

A group of football-sized isopods, officially called Bathynomus giganteus, have been found roaming the seafloor of the Gulf of Mexico. Apparently, these isopods have been roaming the seafloor for 200 or 300 million years.

Bathynomus giganteus remains one of the largest living species today. The species can be found at depths of more than 2,500 meters (8,200 feet). Alphonse Milne-Edwards first described the creature when caught off the Gulf of Mexico in 1879. It may actually be two species combined.

A modern analysis of known giant isopods found subtle yet significant differences in their shape and structure.

One specimen found in 2017, for instance, possessed a slender body compared to other B. giganteus specimens. However, they designated it as that species initially before researchers began questioning its classification.

The curious creature was located between 600 and 800 meters deep off the Yucatán Peninsula.

B. giganteus has been found before in those depths before. However, this specimen remained peculiar. It had a slightly shorter total length, measuring in at 26 centimeters (10 inches). Its antennae was longer than most.

Researchers now suspect this specimen represents a new separate species of Bathynomus. They named the new species B. yucatanensis.

The new species flew under the radar until now because the number of spines on its tail match those of B. giganteus. Researchers also say other specimens from the South China Sea became wrongly labeled as B. kensleyi. In fact, molecular and morphological analyses pointed to them being B. jamesi.

Curious Giant Isopod Found in Gulf of Mexico Off Yucatán Peninsula

“It is increasingly evident that species of Bathynomus may be exceedingly similar in overall appearance, and also that there is a long history of misidentification of species in the genus,” the authors of the analysis write.

These giant isopods share relation with lobsters and other crabs. They share relations with woodlouses, as well.

In comparison to their relatives, however, we know very little about giant isopods. We know that the animals remain well-equipped to deal with major extinction events. Apparently, the species can survive lengthy periods of time without food.

In 2019, when researchers dropped an alligator carcass into the Gulf of Mexico, it took merely a day for a group of giant Bathynomus isopods to devour the meal. Moreover, despite what you may believe, alligator carcasses commonly wash into the Gulf of Mexico because of storms. Giant isopods also love feasting on dead whales.

B. giganteus remains the species closest to B. yucatanensis,” the new paper states.

“This indicates that the two species likely had a common ancestor. Additionally, there may also be other undiscovered Bathynomus spp. in the tropical western Atlantic.”

However, we know one thing: no one wants to encounter a giant isopod alone. The creatures look other-worldly. The fish also remain infamous with fisherman for their antics. Apparently, these fish remain notorious for attacking fish caught in trawls.