Dorset county council said the fossil comes from a pliosaur, a ferocious predator which lived in the oceans 150 million years ago. The skull, which was discovered by a local collector, measures 2.4 meters in length.

Scientists believe the creature would have been 16 meters in length — one of the largest pliosaurs ever found. It was purchased by Dorset County Council for display at a local museum in Dorchester, south-west Britain.

Pliosaurs were a form of plesiosaur, a group of giant aquatic reptiles which lived in the seas at around the same time dinosaurs roamed the Earth, scientists explained. They had short necks and huge, crocodilian-like heads that contained immensely powerful jaws and a set of huge, razor-sharp teeth. They used four paddle-like limbs to propel their bulky bodies through the water, and would have preyed on dolphin-like ichthyosaurs and even other plesiosaurs.

“These creatures were monsters, said David Martill, a palaeontologist from the University of Portsmouth.

“They had massive big muscles on their necks, and you would have imagined that they would bite into the animal and get a good grip, and then with these massive neck muscles they probably would have thrashed the animals around and torn chunks off. It would have been a bit of a blood bath.”