About Austroraptor Dinosaur

Austroraptor (Latin for “Southern Thief”) was a dromaeosaurid dinosaur which lived during the Cretaceous, about 70 million years ago. The sole known surviving fossil, Austroraptor cabazi, was found in Argentina, but the full range of the species is unknown. It is in the same family (but not the same subfamily) as the more popularly known dromaeosaur Velociraptor.

Austroraptor was unusually large for this type of dinosaur, about 16 feet (5 metres) long and 800 pounds (about 350 kilograms). It has short forearms relative to its size, somewhat like the much larger (and unrelated) Tyrannosaurus. The dinosaur would have been slender and carnivorous. It has a strangely elongated skull, and suggests that raptors in the southern hemisphere were both thriving and diversifying even as that family of dinosaurs was declining in the northern hemisphere.

The bones were found in the Allen Formation, in Argentina, which allowed paleontologists to date them to about 70 million years ago. That would put Austroraptor into the Late Cretaceous, running from about 100 million years ago to 65 million years ago, the point at which an asteroid impact event or other cataclysm caused the extinction of the dinosaurs. Dinosaurs flourished during this period, but unless and until more Austroraptor fossils are discovered, it will be difficult to say much more about how this new species fit into the environment of its time. At that time in natural history, the Patagonian region consisted of plains and rivers populated by duck-billed herbivores, which might have been Austroraptor’s food supply.

It was assigned to the unenliagiinae subfamily of dromaeosaurs, making it a relative (at least in taxonomic terms) of Buitreraptor, Neuquenraptor, Rahonavis, and Unenlagia. Unenlagia and Neuquenraptor specimens have also been found in Argentina. As a general rule, the dromaeosaurs were fast, long-tailed, bipedal hunters. At least some were feathered, and at least some may have been pack hunters, although any connection with the sort of pack behaviour presented in fictionalized forms (like the Jurassic Park blockblusters) is really no more than informed speculation.

The sole Austroraptor specimen found to date was located in Argentina in 2008, and designated MML-195. The skeleton at that find was fragmentary and incomplete, featuring pieces of the skull, neck, and vertebrae, an arm bone, several ribs, and a few leg bones. The lead researcher behind the find was Fernando Novas, a paleontologist at the Bernardino Rivadavia Natural History Argentine Museum, who has also discovered (singly or with others) several other Argentine-region dinosaurs, including Austroraptor’s relative, Neuquenraptor. Funding was supplied by the National Geographic Society.