Aucasaurus Facts
Pronunciation: ow-kah-SORE-us
Name meaning: Auca Lizard (after the Auca Mahuevo locality)
| Diet | Carnivore |
| Height | 1.8m |
| Length | 5.5m |
| Weight | 700 kg |
| Environment | Land |
| Era | Cretaceous |
| Period | Late Cretaceous |
| Type | Theropod |
| Location | Argentina |
Aucasaurus was a fearsome medium-sized theropod dinosaur that stalked the ancient landscapes of South America during the Late Cretaceous period, approximately 83.6 million years ago. This powerful predator lived in what is now Argentina, where its remarkably complete skeleton was discovered in the Anacleto Formation of Río Negro Province.
Measuring about 5.5 metres in length and standing roughly 1.8 metres tall at the hip, Aucasaurus was built for predation. Like other members of its family, it possessed a large head filled with sharp, serrated teeth perfect for slicing through flesh. What made Aucasaurus particularly distinctive were its extremely reduced arms, which were even more vestigial than those of its famous relative Carnotaurus. These tiny limbs had almost no fingers at all, representing one of the most extreme examples of arm reduction in theropod evolution.
As a carnivore, Aucasaurus would have hunted other dinosaurs, using its powerful legs to chase down prey across the Cretaceous floodplains. Its skull shows evidence of damage that some paleontologists believe resulted from combat, either with prey or rival predators. The discovery of such a complete skeleton has provided invaluable insights into the anatomy and evolution of South American theropods.
When first described in 2002, Aucasaurus represented the most complete skeleton of its family known to science, making it a crucial piece in understanding the diversity of Cretaceous predators that once dominated the southern continents.
What made Aucasaurus distinctive?
Aucasaurus had extremely reduced arms that were even smaller than those of Carnotaurus, with almost no fingers remaining. Its skull bore small horns or ridges above the eyes, and it possessed the characteristically short, deep skull typical of its family with powerful jaw muscles for delivering devastating bites.
Behaviour
Evidence suggests Aucasaurus may have engaged in violent confrontations, as damage to the skull of the type specimen indicates possible combat before death. Like other large theropods, it was likely an active predator that used its powerful legs and large head to hunt other dinosaurs across the Cretaceous landscape.
Discovery
Aucasaurus was first described by Rodolfo Coria, Philip Currie and Paulina Carabajal in 2002. The original fossils were discovered at Anacleto Formation, Río Negro Province, Argentina.
Aucasaurus FAQ
What did Aucasaurus eat?
Aucasaurus was a carnivore that hunted other dinosaurs. Its sharp, serrated teeth were perfectly designed for slicing through flesh and bone, and it would have preyed upon the various herbivorous dinosaurs that shared its
Late Cretaceous environment in Argentina.
How big was Aucasaurus?
Aucasaurus measured approximately 5.5 metres in length and stood about 1.8 metres tall at the hip. It weighed an estimated 700 kilograms, making it a medium-sized predator - smaller than giants like
Carnotaurus but still a formidable hunter.
When did Aucasaurus live?
Aucasaurus lived during the
Late Cretaceous period, approximately 83.6 million years ago. This places it in the Campanian age, when South America was home to a diverse array of unique dinosaur species.
Where was Aucasaurus found?
Aucasaurus was discovered in Argentina, specifically in the Anacleto Formation of Río Negro Province. This fossil-rich formation has yielded numerous important dinosaur discoveries from the
Late Cretaceous period.
How do you pronounce Aucasaurus?
Aucasaurus is pronounced 'ow-kah-SORE-us', with the emphasis on the final syllable. The name comes from the Auca Mahuevo locality where it was found, combined with the Greek word 'saurus' meaning lizard.
What does Aucasaurus mean?
Aucasaurus means 'Auca Lizard', named after the Auca Mahuevo locality in Argentina where the fossil was discovered. The name honours the geographical region that yielded this remarkable specimen.
How fast could Aucasaurus run?
The exact speed of Aucasaurus is unknown, but based on its leg proportions and body structure, it was likely a capable runner. As an active predator, it would have needed sufficient speed to chase down prey across the Cretaceous landscape.
What type of dinosaur was Aucasaurus?
Aucasaurus was a theropod dinosaur, specifically a member of the Abelisauridae family. These were bipedal carnivorous dinosaurs known for their large heads, powerful legs, and notably reduced arms.
Was Aucasaurus related to birds?
Yes, as a theropod dinosaur, Aucasaurus was related to birds. All theropods, including Aucasaurus, belong to the same evolutionary lineage that eventually gave rise to modern birds, though Aucasaurus itself was not directly ancestral to birds.
How many Aucasaurus fossils have been found?
Only one skeleton of Aucasaurus has been discovered so far - the type specimen found in Argentina. However, this skeleton is remarkably complete, preserved up to the thirteenth tail vertebra, making it one of the most complete specimens of its family when it was described.
