Joaquinraptor: A Formidable Predator of Ancient Argentina
A newly discovered dinosaur, Joaquinraptor, offers a fascinating glimpse into the world of South American predators just before the extinction event 66 million years ago. Unearthed in Argentina’s Chubut Province in 2019, this megaraptoran dinosaur was a significant apex predator in its warm, humid, coastal ecosystem.
Joaquinraptor was a substantial meat-eater, though its predatory style differed markedly from its North American contemporary, Tyrannosaurus rex. While T. rex boasted a massive skull and powerful bite, Joaquinraptor possessed a more lightly built skull, measuring 24-28 inches long, and relatively small, though sharp and curved, teeth. Rather of relying on brute force, Joaquinraptor likely utilized its long arms and three-fingered hands, each tipped with sharp claws – including a prominent sickle-shaped claw on the middle finger – to actively capture prey.
Evidence suggests Joaquinraptor wasn’t a picky eater. The fossil remains included a humerus (upper forelimb bone) from a crocodile within the dinosaur’s jaw, indicating it had been actively consuming this formidable predator when it died. Beyond crocodiles, Joaquinraptor likely preyed upon plant-eating dinosaurs common to the area, including young titanosaurs (long-necked giants), hadrosaurs (duck-billed dinosaurs), and potentially othre species.
The remarkably complete skeleton – including much of the skull, shoulder girdle, forelimbs, hind limbs, vertebrae, and ribs – has allowed paleontologists to estimate the dinosaur was approximately 19 years old at the time of its death, likely sexually mature but perhaps not fully grown.
This discovery is notably important because megaraptorans are a poorly understood group of dinosaurs. Joaquinraptor pushes back the known timeline for this lineage, demonstrating they thrived until the very end of the dinosaur age. The anatomical differences between joaquinraptor and Tyrannosaurus, despite potential evolutionary links, highlight that there was more then one accomplished strategy for being a top predator during the Cretaceous period.
