Move over T Rex, there is a new boss in town.

An adult spinosaurus could weigh up to 20 tonnes and reached 15 metres long, this means it was longer than the tyrannosaurus rex which is traditionally seen as the fiercest and largest beast in the dinosaur kingdom.

New fossils discovered by Nizar Ibrahim and his team have revealed that spinosaurus was an amphibious predator which makes it the only known aquatic dinosaur.

While it was in the water, most of the monstrous meat eater would be invisible except for the sail on its back which was two metres in height.

The fossil remains discovered in Morocco further supports the claims that the spinosaurus spent most of its time in water and not on land.

The first fossils of the dinosaur were destroyed in World War II and there was still a lot palaeontologists did not know about the creature.

This is where Nizar Ibrahim comes in.

Ibrahim was in Erfoud, a town near the border with Algeria and had been approached by a man who showed him a cardboard box with fossils in it, at the time he thought nothing of them.

He was very wrong, what was in the box were spinosaur tail spines which matched fossils that had been found elsewhere. 

After realising this, Ibrahim began an impossible journey; he needed to find out where the fossils in that box had been excavated in order to find the rest of the spinosaurus skeleton.

To do that, he had to track this mystery man down with literally no information other than knowing that he ‘had a moustache’ and just when Ibrahim was about to give up hope, he found him.

“We were in a cafe in Erfoud and I saw my dreams going down the drain. I thought we were never going to find the guy. But at that very moment … a person walked past our table. I caught a glimpse of his face and immediately recognised it. It was the man we were looking for.”

Nizar Ibrahim paleontologist at the University of Chicago and a National Geographic Explorer joined Sean on the show: