Jeff Warren, a local resident, who caught sight of the strange sea creature after going boating at Wolf Island National Wildlife Refuge in Golden Isles, Georgia, told reporters that he had initially taken it for a dead seal, but upon closer inspection saw that it looked like something from prehistoric times.
Warren photographed his find and showed the photos to marine scientists who wondered whether the five-foot-long mystery creature with an elongated neck was a decomposing animal or just a hoax.
With no physical samples left to go on, experts have been unable to determine what the beached creature really was.
According to US Fish and Wildlife Service director Dan Ashe, many sea animals decompose in a way that makes them look like a Plesiosaur, a long-necked marine dinosaur that first existed more than 200 million years ago.
Some experts think that the Georgia creature is not an animal at all.
"That could easily be faked. We think someone's playing a joke on us," marine biologist Quinton White said.
“We've never seen anything like it. There aren't really signs of decomposition, and it looks remarkably intact," he added.
White argued that if the decomposed remains actually belonged to a shark or any other deep-sea creature, the body would look messier.
There was similar confusion in September 2017, when a mysterious fanged creature washed up on a Texas beach in the wake of Hurricane Harvey.