Austroraptor
AW-stro-RAP-tor
"southern thief"
- Lived
- 72 to 66 million years ago, Late Cretaceous
- Diet
- Carnivore
- Length
- about 5 m (16 ft)
- Group
- Theropods, Dromaeosauridae
- Found in
- Argentina
- Named by
- Novas et al. 2008
Size comparison
To scale
Scale in meters
Where its fossils were found
The evidence
Today
70 million years ago
Habitat
It probably lived near river banks, floodplain ponds and low woodland in the Allen Formation landscape. Aeolosaurus, Neuquensaurus and Patagopelta lived in the same region.
Field notes
About Austroraptor
What it was like
Austroraptor was a large, ground-dwelling predator, among the biggest members of the dromaeosaurid family, sometimes called raptors. Its skull was long and low, more like that of some bigger theropods than its smaller dromaeosaurid relatives, and its arms were unusually short.
It probably hunted on two legs, using a large, curved claw on each second toe like other dromaeosaurids. No complete skeleton has been found, so many details of its exact build and proportions remain unclear.
Its world
Austroraptor lived from about 72 to 66 million years ago, in the Late Cretaceous, in what is now Argentina. Its fossils come from the Allen Formation.
It shared its world with the meat-eating Abelisaurus, the long-necked Aeolosaurus and Neuquensaurus, and the armored Patagopelta, among other animals of the region.
How it was found
Novas and colleagues named Austroraptor in 2008. Only two fossil finds have been reported for the genus so far, and its remains are still incomplete, which is why its exact size and proportions remain debated. Austroraptor belongs to the Unenlagiinae, a branch of the dromaeosaurid family found mainly in South America that also includes smaller, lighter-bodied raptors.
Field gallery
More views of Austroraptor
Scenes reconstructed from the available fossil evidence.
1 of 7
Lived alongside
Found in the same rock formations
A rock formation can hold fossils laid down millions of years apart, so not every animal here met Austroraptor.
The evidence
The science behind Austroraptor
Which parts of the picture come from its own bones, and which come from its relatives.
From its own fossils
- Skull bones show a long, low snout with small, cone-shaped teeth.
- The short upper arm was unusual for a large raptor.
- Another partial skeleton adds forearm, hand, foot and tail bones to the known anatomy.
Borrowed from relatives
- Feathers on relatives such as Microraptor and Velociraptor support a feathered body and arms.
- Unenlagia and Buitreraptor help place its incomplete skeleton among southern raptors.
Still unknown
- Its exact adult size and complete body proportions.
- Its feather shape and color, and what its young looked like.
- Whether fish were a regular part of its diet.
Often drawn wrong
- Its arms should stay short rather than resemble the long grasping arms of Deinonychus.
- Its snout was long and low rather than short and deep.
- Webbed paddles and a crocodile-like body have no fossil support.
Discovery timeline
- 2007Close relativeTurner, Makovicky & Norell
- 2008Named itNovas et al.
- 2012New findCurrie & Carabajal
Key papers
The research behind what we know of Austroraptor
Close relative
Found feather attachment bumps in Velociraptor, supporting feathers in related raptors such as Austroraptor.
Feather quill knobs in the dinosaur Velociraptor. Science 317: 1721
Read the paper : Feather quill knobs in the dinosaur Velociraptor (opens in a new tab)Named it
Described a large southern raptor with a long, low skull and unusually short arms.
A bizarre Cretaceous theropod dinosaur from Patagonia and the evolution of Gondwanan dromaeosaurids. Proceedings of the Royal Society B: Biological Sciences 276: 1101-1107
Read the paper : A bizarre Cretaceous theropod dinosaur from Patagonia and the evolution of Gondwanan dromaeosaurids (opens in a new tab)New find
Described another partial skeleton that added forearm, hand and foot bones missing from the first specimen.
A New Specimen ofAustroraptor cabazaiNovas, Pol, Canale, Porfiri and Calvo, 2008 (Dinosauria, Theropoda, Unenlagiidae) from the Latest Cretaceous (Maastrichtian) of Río Negro, Argentina. Ameghiniana 49: 662-667
Read the paper : A New Specimen ofAustroraptor cabazaiNovas, Pol, Canale, Porfiri and Calvo, 2008 (Dinosauria, Theropoda, Unenlagiidae) from the Latest Cretaceous (Maastrichtian) of Río Negro, Argentina (opens in a new tab)
Close relatives
Other members of Dromaeosauridae
Sources: Wikidata