Image: Lukas Panzarin and Andrea Cau for scientific supervision

These dinosaur remains are so bizarre-looking scientists originally thought they were fake — but a closer look reveals a semiaquatic creature with a graceful swan-like neck and sharp velociraptor talons.

Nicknamed “Halszka” (short for Halszkaraptor escuilliei), the dinosaur was a theropod, belonging to a group of bipedal, carnivorous predators including Tyrannosaurus rex. This creature must have looked fascinating in real life — blending avian, reptilian, and amphibian features.

“The first time I examined the specimen, I even questioned whether it was a genuine fossil,” said the study’s lead researcher Andrea Cau said in a statement.

Image: ESRF/Paul Tafforeau

In order to determine the fossil’s legitimacy, the researchers utilized synchrotron multi-resolution X-ray microtomography, which allowed for a close-up picture of internal details without damaging the fossil. The results revealed a real specimen — and a new genus completely.

The synchrotron revealed a snout that would have been sensitive enough to detect movement underwater the way ducks and crocodiles can and rows of tiny teeth for grabbing prey. In addition, this strange dinosaur walked on two legs with sharp talons, but had flippers like a penguin, providing further evidence for the dinosaur’s semi-aquatic nature.

Halszka’s fossilized remains were discovered in southern Mongolia and described in a new study published in the journal Nature.

“Illegally exported from Mongolia, Halszka resided in private collections around the world before it was acquired in 2015 and offered to paleontologists for study and to prepare its return to Mongolia,” study senior researcher Pascal Godefroit stated.