91Èȱ¬

Can you imagine an ancient sea monster with razor-sharp teeth, flipper-like limbs and a head which is longer than most humans are tall?

Well, it turns out that creature really did exist and a fossil of its skull has been discovered.

The creature is called a pliosaur and is thought to have existed around 150-million-years-ago.

The fossil is one of the most complete of its kind ever found, with one expert saying it is "unique".

The skull will feature in a 91Èȱ¬ documentary shown on New Year's Day with everyone's favourite nature presenter Sir David Attenborough.

The fossil was extracted from the cliff's of Dorset's Jurassic Coast and is a whopping two metres (6.5ft) long.

Steve Etches, who is a fossil expert, says there isn't another anywhere else like it.

"Worldwide, there's hardly any specimens ever found to that level of detail. And if they are, a lot of the bits are missing, whereas this, although it's slightly distorted - it's got every bone present."

The skull has 130 long, razor sharp teeth which the creature could use to kill its prey in a single bite.

Experts say the pliosaur would have been 10-12m in length and would have used its four flipper-like limbs to speed through the water.

"The animal would have been so massive that I think it would have been able to prey effectively on anything that was unfortunate enough to be in its space," says Dr Andre Rowe from Bristol University.

"I have no doubt that this was sort of like an underwater T. Rex."

Initially the tip of the snout was spotted by fossil enthusiast Phil Jacobs while he was walking along a beach near Kimmeridge Bay on southern England's famous World Heritage Jurassic Coast.

Then, over a series of weeks, the rest of the skull was extracted from the crumbling cliffs by a team dangling from ropes.

The skull will go on display next year at a museum, so more can be learnt about this creature, but experts believe that the rest of the fossil could be still be in the cliff.

Steve Etches said: "This part of the cliff line is going back by feet a year. And it won't be very long before the rest of the pliosaur drops out and gets lost. It's a once in a lifetime opportunity."

What do you think of this giant sea monster? Let us know in the comments...