Austroraptor

Austroraptor was a remarkable, large-bodied dromaeosaurid dinosaur discovered in the Late Cretaceous rocks of Rio Negro Province, Argentina. Unlike northern raptors such as Velociraptor and Deinonychus, Austroraptor reached lengths of five to six metres, making it one of the largest dromaeosaurs known. It belonged to the Unenlagiinae, a specialised Gondwanan subfamily adapted for unique predatory habits. Austroraptor had a remarkably low, elongated snout lined with numerous small, conical, non-serrated teeth reminiscent of spinosaurids and crocodiles. This distinctive jaw anatomy suggests it was well equipped for capturing slippery aquatic prey such as fish, alongside smaller terrestrial vertebrates. Surprisingly for a dromaeosaur, its forearms were disproportionately short and stubby, showing that southern raptors developed highly divergent body plans from their feathered northern cousins.

It possessed unusually diminutive forearms, contrasting sharply with the long wings of typical northern dromaeosaurs.

Where and when

Austroraptor lived in the Late Cretaceous, from 72 to 69 million years ago (Campanian-Maastrichtian age). Its remains come from Argentina, in the Allen Formation.

The numbers

Length 5.5 m (estimates run from 5 to 6 m). Mass about 370 kg. Hip height about 1.7 m. That is 3.2 human-lengths, or 0.49 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, first ma, last ma, hip height.

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