Livyatan. Illustration of the largest marine predator Livyatan. Livyatan is an extinct species of physeteroid whale, which lived during the Miocene epoch, approximately 12-13 million years ago. Livyatan melvillei had a body length of 13.5 to 17.5 metres, about the same as a modern adult male sperm whale. The skull of Livyatan melvillei is 3 metres long. Livyatan melvillei is one of the largest raptorial predators yet known, with whale experts using the phrase the biggest tetrapod bite ever found to explain their find. Livyatan melvillei would have been a top predator of its time along with the giant shark, C. megalodon. Livyatan melvillei is likely to have preyed upon 7-10-metre baleen whales, seals and dolphins.