On a vast, arid plateau in southern Argentina, a group of researchers sift through the sand and hardened rock in the hope of discovering pieces of prehistoric history.
The remote location was once a reptilian paradise, and in April, the researchers’ work paid off with the discovery of a new species of dinosaur, a 6-foot-tall titanosaur.
Now, just one month later, the team has done it again.
The researchers were back at the La Colonia Formation of Patagonia when they discovered another set of fossilized bones, according to a study published on May 21 in the journal Cladistics.
It was a partial skeleton, but with many critical fragments including pieces of skull bones, a nearly complete set of back bones, a complete hip, tail bones and nearly complete leg bones, according to a May 21 news release from National Geographic, which funded the project.
The sprawling landscape was once part of Gondwana, a massive supercontinent during the Cretaceous period known for its high diversity and fearsome predators, and this dinosaur fit right in.
“The new species is an abelisaurid called Koleken inakayali, a name that derives from the language of the Tehuelche people of Central Patagonia and refers to the claystone the animal was found in and the Tehuelche leader, Inakayal,” National Geographic said.
It’s only the second known abelisaurid to have lived in the area during the Late Cretaceous Epoch, around 70 million years ago, according to the release, and it coexisted with the titanosaur species identified in April.
The other known abelisaurid, Carnotaurus sastrei or the “meat bull,” gained notoriety for its inclusion in the “Jurassic World” movie and can be identified by its small arms and horned head, National Geographic said.
This new species is slightly smaller, according to the study, and is missing those notable horns. Overall, the shape of its skull is different, evident from the fragments that were recovered in Argentina.
“This finding sheds light on the diversity of abelisaurid theropods in Patagonia right before the mass extinction event,” National Geographic Explorer Diego Pol, and lead author on the study, said in the release. “Our study also analyzes the evolution of abelisaurids and their relatives through time, and identifies pulses of accelerated rates of skull evolution in the Early Cretaceous. It expands what we know about abelisaurids living in this area during the Cretaceous Period and shows that they were more diverse than previously understood.”
So what did the dinosaur actually look like?
The new species is part of a group of dinosaurs known as theropods, carnivorous creatures that walked on two legs and ranged from relatively small to massive like the Tyrannosaurus rex.
Like the T. rex, the abelisaurid has large, strong back legs, a long tail used for balance and incredibly disproportionate front limbs. On the new species, the “arms” are all but gone and lay prone on the front of the dinosaur’s body.
Compared to the “meat bull,” its head is rounded on the top with small lumps above the eyes, much smaller than the horns seen on the other species.
“The discovery of Koleken inakayali significantly furthers our collective scientific understanding of the dinosaur era,” Ian Miller, the National Geographic Society’s Chief Science and Innovation Officer, said in the release. “The addition of Koleken inakayali to the La Colonia Formation fauna continues to demonstrate that the Formation is amongst the most important end-Cretaceous dinosaur-bearing rock units in the world.”
Pol and his team are working to build a database of dinosaurs and vertebrates that lived throughout the Patagonia during the Cretaceous period, which lasted 15 million years, according to National Geographic. Their work will continue in the region.
The La Colonia Formation in central Patagonia is located in Chubut Province in southern Argentina.
