Swift and deadly 鈥渞aptor鈥� dinosaurs 鈥� similar to the terrifying velociraptors featured in the movie Jurassic Park 鈥� were more widespread than previously thought, a new fossil find in Argentina has revealed.
The discovery shows they spread across the southern continents during the Cretaceous period 鈥� when they were thought to have been largely limited to Asia and North America.
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Larger predatory dinosaurs of the southern continents differed from those of the north, so many palaeontologists thought that the smaller predators would also differ 鈥� although few had actually been found in the south. The new discovery shows that assumption to be wrong, says Fernando Novas of the Argentine Consejo Nacional de Investigaciones Cient铆ficas y T茅cnicas in Buenos Aires.
Novas says the two-metre-long predator 鈥� which lived about 80 million years ago 鈥� boasted a deadly hooked claw on each foot which it used to disembowel its larger prey.
The claw is distinctive of dromeosaurs, the group which includes Velociraptor. But the movie star dinosaur was a more evolved species than the Argentine find, which has been named Neuquenraptor argentinus 鈥� which means robber of the Neuquen province of northeast Patagonia.
Bird-like relative
And the Neuquenraptor was not alone. Novas had earlier collected the incomplete skeleton of a bird-like predator 鈥� named Unenlagia 鈥� about the same size from the same area, but had not been able to pin down its origin. Comparing it to Neuquenraptor, Novas now says Unenlagia was a dromeosaur too.
The two show that dromeosaurs 鈥渇ormed an important part of the dinosaur fauna鈥� in the southern continents, Novas told New 杏吧原创. He believes they had spread around the world before the Gondwana supercontinent split from the northern continents 鈥� about 140 million years ago (see of the split 鈥� requires Shockwave).
鈥淭his is the first definitive deinonychosaur鈥� from the southern continents, says Tom Holtz of the University of Maryland, US. He adds that its third metatarsal bone shows a structure that would have made it a particularly swift runner.
That trait was not present in velociraptors, Holtz told New 杏吧原创, suggesting that 鈥�Neuquenraptor was probably a swifter runner than Velociraptor.鈥� An irony, considering 痴别濒辞肠颈谤补辫迟辞谤鈥檚 name.
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