Giant salamander-like creature was a top predator in the ice age before the dinosaurs

Forty million years before the first dinosaurs evolved, a ferocious predator lurked in swampy waters. Its skull alone was over two feet long. It lay in wait, its jaws open wide, preparing to clamp down its interlocking jaws on any prey unwise enough to swim past. Meet Gaiasia jennyae, the swamp creature with a toilet seat-shaped head. Scientists described the newly-discovered fossil in a paper in the journal Nature.