A hunter in Montana accidentally discovered this prehistoric sea monster

Seven years after an elk hunter accidentally stumbled on a fossil in Montana's Charles M. Russell National Wildlife Refuge, the new species he found by mistake has a name — Nakonanectes bradti. 

"Nakonanectes" is to honor the native Nakona people of what is now Montana, and "bradti" is after David Bradt, the hunter who discovered the fossil, according to a statement from the University of Alaska, Fairbanks.

When Bradt first discovered the fossil in a stream in 2010, he believed it was from a dinosaur. "It's about the size of a cow, and I'm thinking it's a triceratops," he told the Associated Press. But when paleontologists excavated and studied the fossil, it turned out it belonged to a prehistoric sea creature that lived in an inland sea east of the Rocky Mountains some 70 million years ago, according to the AP.

The excavation site where Nakonanectes bradti was accidentally discovered by an elk hunter.Erin Clark/AP

The creature, as paleontologists realized, was a previously undiscovered species of elasmosaur, a carnivorous sea-dweller that had a tiny head and large, paddle-shaped limbs. Most elasmosaurs, the AP reported, had long necks that stretched up to 18 feet long. But Nakonanectes bradti, the new species that Bradt stumbled upon, had a much shorter neck.

"This group is famous for having ridiculously long necks, I mean necks that have as many as 76 vertebrae," Patrick Druckenmiller, a paleontologist at the University of Alaska Museum of the North, told the AP. "What absolutely shocked us when we dug it out — it only had somewhere around 40 vertebrae."

Nakonanectes bradti, the short-necked elasmosaur, has now officially joined the canon of known prehistoric sea creatures. The inland sea in which Nakonanectes bradti lived covered a large swath of what is now North America — it stretched from Montana to Minnesota and from Canada to the Gulf of Mexico, the AP reported.

There could be more fossils out there that belong to other as-yet-undiscovered species, Druckenmiller said. Someone just needs to find them.