Huge 180-million-year-old ‘sea dragon’ fossil found in UK

The 10m-long giant ‘sea dragon’ fossil is one of the most complete fossils ever found in the UK.

This is the largest and most complete ichthyosaur fossil found in the UK. This giant marine reptile shaped like a dolphin is a prime example of convergent evolution.

This “sea dragon” is similar to modern fish and dolphins, with four legs that have fully evolved into flippers, and some have dorsal fins. Their heads are elongated like arrows, and their jaws are often equipped with conical sharp teeth to catch smaller prey.

Some species have teeth as large as blades that can attack larger animals. Their eyes are large, presumably to catch prey in the depths. The neck is short, and later species have rather rigid bodies. They also have a more upright tail fin for powerful acceleration. The spine consists of simple disc-shaped vertebrae that extend to the lower lobe of the caudal fin. Maybe a warm-blooded animal. Lizards are air-breathing, mobile, and probably warm-blooded.

Huge 180-million-year-old

This sea dragon thrived in the Mesozoic, and according to much fossil evidence, they first appeared around 245 million years ago, and at least one species survived into the early epoch around 90 million years ago. During the mid-Triassic period, ichthyosaurs evolved from a group of unidentified land reptiles to aquatic creatures that resembled the ancestors of modern dolphins and whales.

They became particularly abundant during the Jurassic, until they were gradually replaced in the Cretaceous by the dominant aquatic predators of another reptilian order, the plesiosaurs. For unknown reasons, fish lizards became extinct at the end of the Cretaceous period.

Huge 180-million-year-old

The fossil “sea dragon” found in the UK is more than 10 meters long and weighs about 1 ton, and has been raised for conservation and research. The head alone, the skull was found to be about 2 meters long.

Huge 180-million-year-old

In February 2021, Leicestershire and Rutland Wildlife Trust conservation team leader Joe Davis discovered a similar fossil on a lagoon island that was being drained for re-landscape. Davis said:

“This discovery is fascinating and a real career highlight. It’s great to learn a lot from the discovery of this ichthyosaur as we have always lived and primarily inhabited the area. The sea buried this living fossil. Now, again, Rutland waters are a haven for wetland wildlife.”

Dr Dean Lomax, a paleontologist at the University of Manchester, has studied thousands of ichthyosaurs and led the excavation team. He says: “It has been a privilege to lead the excavations. England is home to ichthyosaurs, as the first ichthyosaur fossils were unearthed in this country more than 200 years ago.