Edmonton professor discovers new 'megaraptor' in Argentina

More than eight metres long and brandishing "can-opener" claws, the creature now known as murusraptor barrosaensis was not something to trifle with.

University of Alberta professor Philip Currie and his team freed the bones from a cliff in Argentina more than a decade ago.

Now a paper published this month shows the specimen may very well be a new species of megaraptorid, which is essentially a giant raptor.

According to a release about the discovery, the specimen is a cousin of a trio of theropods: megaraptor, orkoraptor and aerosteon — medium-sized dinosaurs that have "large claws and air-filled birdlike bones." 

"This is a super-cool specimen from a very enigmatic family of big dinosaurs," said Currie. "Because we have most of the skeleton in a single entity, it really helps consolidate their relationships to other animals." 

The raptors lived about 80 million years ago in the Cretaceous period. 

A clue that helped the scientists discover the genus of the carnivorous dinosaur was the placement of the claws. 

"What was thought to be the foot claws — the big can-opener claw of a dromaeosaur or raptor — were actually from the hands. We discovered all sorts of things through the course of our research," said Currie.

Another clue was found in the air-filled bones in its hips. 

"The hips were really interesting because they are pneumatic, clearly air-filled, not the kind of thing you expect to see in a big theropod."

Currie wrote that the skeleton may help discern the evolutionary origins of the megaraptorid group.

In an article published in the July 20 edition of the scientific journal Plos One, Currie and fellow paleontologist Rodolfo Coria wrote that the skeleton is "one of the most informative megaraptorids known."

When they first found the skeleton in 2000, they didn't know exactly what it was.

"It was very evident that it was a beautifully preserved specimen of pure white in red rock."

The cliff evacuation was a difficult one but actually played a role in its name, murusraptor barrosaensis.  

"Murus" is a Latin term for "wall," referring to the discovery of the specimen in the wall of a canyon; "barrosaensis" alludes to Sierra Barrosa, the locality where it was collected," Currie and Coria wrote in the paper. 

Currie likened Sierra Barrosa to Drumheller, as "a small place with lots of dinosaurs around."

"Probably half of the South American dinosaurs are within 200 kilometres of the town."