280 million-year-old swamp monster with 'big, flat toilet seat-shaped head' discovered in Namibia

Researchers in Namibia have discovered fossils from a huge, extinct swamp creature with a toilet seat-shaped skull.

Gaiasia jennyae existed around 280 million years ago — about 40 million years before the first dinosaurs evolved — and offers a glimpse into the early evolution of tetrapods, or four-limbed vertebrates. 

Its skull was more than 2 feet (0.6 meters) long, and researchers estimate the entire animal could have been  to 8.2 feet (2.5 m) long, potentially making it the biggest creature of its kind, according to a statement. 

Researchers described the swamp creature in a study published Wednesday (July 3) in the journal Nature.

"Gaiasia jennyae was considerably larger than a person, and it probably hung out near the bottom of swamps and lakes," study co-lead author Jason Pardo, a researcher at the Field Museum in Chicago, said in a separate statement.

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G. jennyae had interlocking jaws that enabled it to hunt for prey. The researchers believe it was likely the apex predator in its swampy ecosystem.