Basilosaurus was a genus of Basilosaurid whales. It was enormous, traditionally being depicted as the biggest mammal predator ever. Basilosaurus rivaled or exceeded the modern sperm whale in size Basilosaurus would have grown to 60-70 feet.
Basilosaurus was reptilian in design and at one point thought to have been a reptile. Two species are known from Africa, with many more from the United States of America. This enormous whale would have been a deadly predator; its jaws were incredibly powerful and would give Basilosaurus a powerful grip on its prey, which may have included other, smaller whales. However, Basilosaurus most likely preyed on fish sharks and other sea animals.