The latest issue of Nature Communications reports the latest discovery of a species of South American predatory dinosaur, named J. casali. This species, a member of the theropod family Megaraptoridae, dates back to the Late Cretaceous period, 70 to 66 million years ago, and was the region’s top predator.
Meganapteridae are carnivorous theropod dinosaurs found in Asia, Australia, and South America, characterized by elongated skulls, powerful forearms, and large claws. However, knowledge of this group is limited, primarily due to a lack of complete fossils.
Scientists from the Patagonian Institute of Geology and Paleontology in Argentina have described a remarkably well-preserved, partially cross-linked fossil containing a large portion of the skull, forelimbs, ribs, and vertebrae. The specimen dates to the Late Cretaceous. Based on skeletal microstructure, the specimen is considered an adult, but likely not fully mature, and was likely around 19 years old at the time of death. The dinosaur was likely approximately 7 meters long and weighed over 1,000 kilograms.
Sedimentary evidence suggests it lived in a warm, humid floodplain environment. A crocodile leg bone fossil, found beneath J. casali’s jaw, reveals its feeding habits, suggesting it may have been a top predator in the region. Scientists estimate that this dinosaur survived until the end of the Cretaceous period, along with other non-avian dinosaurs.
