‘Stocky Dragon,’ A European Velociraptor Relative, Described

Monday, August 30 1:30 pm

Balaur bondoc — the first reasonably complete skeleton of a carnivorous dinosaur from the last part of the Age of Dinosaurs in Europe, a description of which appears as the cover article in Proceedings of the National Academy of Sciences today — provides insight into an ecosystem very different from that of today. Europe at the end of the Cretaceous was an island archipelago dominated by smaller and more primitive animals than related species living on larger landmasses. Balaur bondoc, though similar in size to its relative, Velociraptor, has unusual features.

“We’ve all been waiting for something like this,” says Mark Norell, chair of the Division of Paleontology at the Museum. “Balaur bondoc is heavy, with unexpectedly stocky limbs and fused bones. It shows just how unusual the fauna of the area was during the waning years of the dinosaur era.”

Balaur bondoc, whose scientific name means “stocky dragon,” is a partial skeleton that was unearthed in Romania. It has 20 unique features when compared to its nearest relatives, including a re-evolved functional big toe with a large claw that can be hyperextended, presumably to slash prey. This feature, when combined with the large claw on the second toe that is typical of Balaur’s relatives, makes the new species double-clawed. Its feet and legs are short and stocky, with bones fused together, and the pelvis has enormous muscle attachment areas, indicating that this species was adapted for strength over speed. Finally, its hand is atrophied and some of the bones are fused, features that would have made grasping difficult.

“Balaur is a new breed of predatory dinosaur,” says Stephen Brusatte, a graduate student at Columbia University who is affiliated with the Museum. “Its anatomy shows that it probably hunted in a different way than its less stocky relatives. Compared to Velociraptor, Balaur was probably more of a kickboxer than a sprinter, and it might have been able to take down larger animals than itself, as many carnivores do today.”

The fossilized hindlimb Balaur bondoc showing the double sickle claws of the foot, one of 20 unique features found on a Late Cretaceous island in what is now Europe. Credit: Mick Ellison