Thanks to a team of European paleontologists, the Velociraptor just got a new, extremely awkward cousin: the Halszkaraptor. According to a story in The Atlantic, their study, published today in Nature, is based on a fossil that had been smuggled out of Mongolia and found its way into the hands of a Belgian paleontologist named Pascal Godefroit. Only a portion of the creature was visible from outside the hunk of rock, but even that was enough to tell this was a dinosaur unlike any we’ve seen before, an amphibious half-raptor, half-swan predator so bizarre that the scientists thought it could have been fake.

“It was so strange that we suspected that it might have been a chimera—a mix of different skeletons glued together. It wouldn’t be the first time,” Andrea Cau, one of the authors of the study, told The Atlantic. “We had to be sure that it was a real dinosaur and not a fake.” To do that, the team used a particle accelerator to scan the rock housing the fossil. They determined it was the real deal and named the monstrosity Halszkaraptor escuilliei, after Halszka Osmólska, a Polish paleontologist, and François Escuillié, the French collector who had bought the fossil and got it to Godefroit.

The study concludes that this is the first amphibious dinosaur we know of, with its swan-like neck, duck bill, and not-quite-flipper arms probably making it a great swimmer capable of chasing down fish and plucking them out of the water. The rest of its body, meanwhile, was kind of a mess, with long legs that weren’t particularly good for running and a long tail that wasn’t heavy enough to counterbalance its ridiculous neck. Cau told The Atlantic it likely turned out this way by adapting to an “unstable environment” that cycled between droughts and abundant water. The one thing the researchers can’t quite nail down is how Halszkaraptor’s arms functioned. Although the bones resemble those of modern swimming birds like penguins, Cau says they don’t have enough information about the skeleton to determine if halszkaraptor swam like one.