Kostensuchus atrox discovered in March 2020, Argentina's Chorrillo Formation, 70 million years old Fossil found after months of excavation during pandemic Hypercarnivore apex predator with robust skull, 50+ serrated teeth like Tyrannosaurus rex, longer limbs Estimated 3.5 meters long, 250 kg Dominant predator hunting dinosaurs in late Cretaceous Discovery expands knowledge of crocodyliforms in high latitudes, before extinction event.