On a semiarid Patagonian landscape 85 million years ago, a formidable meat-eater called Tratayenia rosalesi reigned as the apex predator, part of an enigmatic dinosaur group that menaced South America and Australia for tens of millions of years.

Scientists on Wednesday described Tratayenia, a two-legged beast up to about 30 feet (9 meters) long, based on fossils unearthed in Argentina’s Neuquen province, adding another impressive dinosaur to the list of those that inhabited Patagonia during the Cretaceous Period.

It was a member of a group called megaraptorids that lived in the Southern Hemisphere from about 105 to 85 million years ago. The group was recognized by paleontologists only in the past few years, and all of its members — including Tratayenia — are known only from incomplete skeletons.

“Megaraptorids, although still mysterious, seem to have been a pretty badass bunch of predatory dinosaurs,” said paleontologist Matt Lamanna of the Carnegie Museum of Natural History in Pittsburgh.

“Using the remains of different species, including Tratayenia, we can make something like a ‘police composite’ of a megaraptorid skeleton,” Lamanna added …  (read more)

via The Japan Times