Many people see sea monsters as something from myth and legends told by pirates and the Scottish, but in the Mesozoic, that ended 66 million years ago, they were very real indeed. This is a low-down of the new pliosaur that was discovered recently in Dorset.
So here you have it, Pliosaurus kevani! His skull ALONE is 2.4m long and is said to be the most powerful predator that ever lived and is larger than Liopleurodon! It is said that Pliosaurus kevani may have weighed 12 tonnes! Not only was this marine reptile record-breaking-ly massive, but it was excellently preserved and a very significant discovery. Below is an image of the cranium of Pliosaurus kevani n. sp. in ventral view.
So why is it so different that it can be classed as a new species? Apart from its larger size, its lower jaw was also very long from front to back whereas other species of pliosaurs had shorter ones. Also, its teeth grew upwards and outwards compared to other pliosaurs’ teeth that went straight up.
This creature lived during the Middle Jurassic until the early Late Cretaceous and was named in honour of Kevan Sheehan, a local collector who discovered this beast in the cliffs near Weymouth in 2003. This 68 year old was dedicated, as it took him 5 years to unearth the skull from the cliff.
Pliosaurs are known for being the top predators in Mesozoic seas; living in water meant that they had space to grow to vast sizes and trihedral or subtrihedral teeth suggest a macro-diet, feeding on ichthyosaurs, plesiosaurs (Nessy) and anything else they could get their flippers on. Pliosaurus kevani had some teeth preserved in his skull. Four were prepared for analysis. This pliosaur’s teeth were subtrihedral, which are conical and sharp, its jaw closing with great gusto, teeth interlocking so no prey could escape. It could have swallowed a great white whole and had a bite powerful enough to rip a car in half.
Maximum body size for pliosaurs seemed to increase as these animals evolved from the Jurassic to Cretaceous. Lower Jurassic pliosaurs are relatively small (but still pretty big), with their skulls only being 180mm in the Early Jurassic, reaching 1540mm in the Middle Jurassic. This astonishing size is from Liopleurodon ferox from the Callovian Oxford Clay Formation. Some Early Cretaceous pliosaurids were even larger than this, with skull lengths maybe reaching 2360 mm! As I mentioned earlier, its skull being 2.4m long, P. kevani is larger than all the above! Below is a graph representing maximum skull length of Jurassic–Cretaceous pliosaurids.
So there you have it, Pliosaurus kevani. Its skull is 95% complete and after being sold to the county council for £10,000, is now on display at Dorset County Museum in Dorchester.
Also, thanks to my dad for saving the Metro newspaper to show me the picture!