The discovery of a 150-million-year-old pliosaur skull rocked the world in 2023, after it was retrieved from 12 meters (39 feet) up a cliff along the Jurassic Coast. It belonged to a pliosaur, an ancient marine reptile with a bite force that could’ve bested Tyrannosaurus rex in a fight, and it’s just been entered into the Guinness Book Of World Records.
Dubbed “SeaRex,” the pliosaur skull is 95 percent complete by surface area, making it the most complete skull of its kind on the planet. It contains almost all of its original bones, with 130 spiky teeth interlocked, just as they would have been when the pliosaur was swimming around the ocean 150 million years ago.
“I have studied many Kimmeridgian pliosaurs but have never seen one that is quite so well preserved as [this],” pliosaur expert Dr Judyth Sassoon from the University of Bristol told Guinness World Records. “It contains a lot of anatomical details in a single specimen that are only found partially preserved in other specimens.”
The skull was discovered after fossil enthusiast Phil Jacobs found a snout on the beach in Dorset. He recorded a video and sent it to fossil expert Steve Etches MBE, proprietor of the Etches Collection where the pliosaur skull will go on display.
“We put a drone up and scanned all the way along the cliff, and then found what looked to be the rest of it stuck out. We needed to confirm that, so that meant a trip down the cliff on ropes to actually go down and see it. From there, we realised that it was preserved upside and that was the reason it looked so weird,” Etches told IFLScience when we went to see the skull.
You look on these programs and they’re in a quarry and it’s dead easy, and they have their cups of tea and they brush away – this was nothing like that, I can tell you.
Steve Etches, MBE
“It didn’t take very long to actually locate where the thing was, but it was right in the middle of a cliff. And you think, ‘Oh God.’ You look on these programs and they’re in a quarry and it’s dead easy, and they have their cups of tea and they brush away – this was nothing like that, I can tell you.”
The test of endurance of getting the 2-meter (6-foot) skull out of the cliff is told in great detail in the BBC program Attenborough And The Giant Sea Monster. For all his experience with the natural world, it’s safe to say fossil-fanatic Sir David Attenborough was still blown away by the discovery.

It’s rare to find a fossil like this that’s not disarticulated, meaning it looks as it would have in life.
Image credit: (C) IFLScience
“That is one of the biggest skulls you’ve ever seen,” Sir David Attenborough said in a release emailed to IFLScience. “I mean, it’s huge and so although I was aware of the tip that was first discovered I hadn’t fully appreciated how big the whole head would be and it’s enormous. Sheer scale was what first impressed me.”
“The thing about the skull is that it’s not only by far the most informative part of the body, it is by far the most delicate too,” he added. And it’s the detail, and that is so rare to find it. [T]his is as near-perfect as it can possibly get.”
“One of the scientists, Andre [Rowe], he says it’s a one in a million, no! One in a billion fossil…” added executive producer Mike Gunton.
The skull is now on display at the Etches Collection in Kimmeridge, Dorset, with Steve Etches describing it as “one of, if not the most important specimen ever to come out from the Kimmeridge clay, and globally, this is one of the best specimens you’ll see.” The Etches collection is now requesting donations to “Rescue the SeaRex” as it’s believed that the skull isn’t all there is to be studied along this stretch of the Jurassic Coast.
“The rest of the body is there, I’m sure,” fossil expert Chris Moore, who was instrumental in excavating the skull, told IFLScience. “It’s slightly disarticulated, so it’s come apart, but it’s all there.”
“We took out part of the shoulder blade, some paddle digits and some of the vertebrae, that were inside of the head and you could see there were more bones going in. So, I’m sure the whole animal is there.”
Find out more here if you’d like to help them find out.
Source Link: “One-In-A-Billion” Giant Sea Monster Skull Breaks A World Record