A dinosaur unearthed on the Isle of Wight off England's coast may be the largest land predator that ever roamed Europe, say scientists.
It was a cross between a Tyrannosaurus rex and a great white shark, as it was also able to hunt in water.
The terrifying creature had a face like a crocodile, razor-sharp teeth and claws, and a whip-like tail.
It was as big as a school bus at over 33 feet long and weighing more than 5 tons. The fossilized bones include large pelvic and tail vertebrae among other pieces.
They were dug up near Compton Chine, a small gully on the Isle of Wight's southwest coast that drains a nearby plain.
The fossils date back 125 million years to a period of rising sea levels.
The bipedal beast had short arms - just like a T-rex. Stalking lagoons and sandflats, its bone-crushing jaws snapped large fish in half, and even other dinosaurs.
It was a member of the spinosaurids, meaning "spine lizard." They were the first dinosaurs to swim.
Bones grew on their backs to form what is referred to as a "sail." They were up to 7 feet long and connected by skin.
Lead author Chris Barker, a paleontology student at the University of Southampton, said it was a killer of immense proportions.
He explained: "This was a huge animal, exceeding 10 meters (33 feet) in length, and judging from some of the dimensions, probably represents the largest predatory dinosaur ever found in Europe.
"It is just a shame it is only known from such scant material."
The new species was entombed inside a sandstone bed at a prehistoric graveyard called the Vectis Formation.
It has been unofficially named the "White Rock spinosaurid" after the geological layer in which it was found.
The isle has been dubbed Dinosaur Island for its treasures, which are on display at a purpose-built museum in Sandown on the Isle of Wight.
More dinosaur bones have been dug up there than anywhere else in Europe. Its position at the time was roughly where Gibraltar is now. Most are from the Cretaceous, but dinosaurs are preserved from more than one section of history - and some are little understood.
Corresponding author Neil Gostling, a lecturer in evolution at Southampton, said: "Unusually, this specimen eroded out of the Vectis Formation, which is notoriously poor in dinosaur fossils.
"It is likely to be the youngest spinosaur material yet known from the UK."
Marks on the bone showed - even after death - that the body of this monster probably supported a range of scavengers and decomposers.
Co-author Jeremy Lockwood, a Ph.D. student at the University of Portsmouth, said: "Most of these amazing fossils were found by Nick Chase, one of Britain's most skilled dinosaur hunters, who sadly died just before the COVID epidemic.
"I was searching for remains of this dinosaur with Nick and found a lump of pelvis with tunnels bored into it, each about the size of my index finger.
"We think they were caused by bone-eating larvae of a type of scavenging beetle. It is an interesting thought that this giant killer wound up becoming a meal for a host of giant insects."
The researchers now plan to strip thin sections to scan the internal properties of the bones to shed light on the animal's growth rate and possible age.
Co-author Darren Naish, from Southampton, said: "Because it's only known from fragments at the moment, we haven't given it a formal scientific name. We hope additional remains will turn up in time."
He added: "This new animal bolsters our previous argument - published last year - that spinosaurid dinosaurs originated and diversified in western Europe before becoming more widespread."
In September, the same team announced two other spinosaurs had been discovered nearby.
They named one "hell heron" because it hunted like the wading bird. The latest is described in the journal PeerJ.
