Somerset’s Giant Sea Monster! Huge ichthyosaur, twice the size of a London bus, roamed Britain 200 million years ago, study reveals

  • Somerset’s coastline was home to a huge ichthyosaur 200 million years ago
  • It was no less than 25 meters long, twice as long as a London bus

It is best known for Glastonbury, cider and cheddar.

But Somerset now has a new claim to fame: its coastline was once home to the largest species of marine reptiles ever discovered.

Experts have revealed that a huge ichthyosaur, twice the size of a bus, swam in the sea near Somerset 200 million years ago.

Archaeologists from the University of Bristol and the University of Manchester have in recent years pieced together fragments of a jawbone excavated from the Westbury Mudstone Formation.

The new bone was similar in size and shape to another jawbone collected from the same rock formation just a few miles away.

It is best known for Glastonbury, cider and cheddar. But Somerset now has a new claim to fame – as its coastline was once home to the largest species of marine reptiles ever discovered

Archaeologists from the University of Bristol and the University of Manchester have in recent years pieced together fragments of a jawbone excavated from the Westbury Mudstone Formation.

Archaeologists from the University of Bristol and the University of Manchester have in recent years pieced together fragments of a jawbone excavated from the Westbury Mudstone Formation.

Together, they now believe that these two jawbones belong to a previously undescribed species of ichthyosaur – a group of enormous, ocean-dwelling reptiles from the age of dinosaurs.

Based on the length of these bones, the new species, named Ichthyotitan severnensis, could have been as long as 25 meters – twice the length of a London bus.

Ichthyosaurs, many of which resemble modern dolphins, first evolved during the Early Triassic, about 250 million years ago.

They are distant relatives of lizards and snakes and could move through the water at very high speeds.

They hunted a range of animals, such as octopus, squid and cuttlefish, with the long, thin jaws containing numerous sharp teeth.

Within a few million years, some had evolved to lengths of at least 15 meters (49 feet), and by the Late Triassic the largest ichthyosaurs had evolved, including the newly described species.

The new species, called Ichthyotitan severnensis, may have been as long as 25 meters – twice the length of a London bus

The new species, called Ichthyotitan severnensis, may have been as long as 25 meters – twice the length of a London bus

The fossils were unearthed in the Westbury Mudstone Formation, just southwest of Bristol

The fossils were unearthed in the Westbury Mudstone Formation, just southwest of Bristol

However, this reign did not necessarily last long.

While some species of ichthyosaurs continued to roam the oceans for millions of years, these “giant ichthyosaurs” are thought to have become extinct in a major extinction event 200 million years ago.

This unique group of reptiles has never again reached such a gigantic size.

Dr. Dean Lomax, who led the research, said: ‘In 2018 my team studied and described (a) giant jawbone and we had hoped that one day another would come to light.

‘This new specimen is more complete, better preserved and shows that we now have two of these gigantic bones with a unique shape and structure.

‘It’s quite remarkable to think that giant ichthyosaurs the size of a blue whale swam in the oceans around the British Triassic.

‘These jawbones provide tantalizing evidence that a complete skull or skeleton of one of these giants may one day be found. You never know.’

The findings have been published in the journal Plos One.

What We Know About Ichthyosaurs – Marine Predators That Ruled the Waters in the Age of Dinosaurs

Ichthyosaurs were a highly successful group of sea-going reptiles that became extinct about 90 million years ago.

They appeared during the Triassic, reached their peak during the Jurassic and disappeared during the Cretaceous.

Often misidentified as swimming dinosaurs, these reptiles appeared before the first dinosaurs had emerged.

They evolved from an as-yet unidentified land reptile that moved back into the water.

The enormous animals, which remained at the top of the food chain for millions of years, evolved a streamlined, fish-like shape built for speed.

Scientists calculate that one species had a cruising speed of 36 km/h.

The largest species of ichthyosaur is believed to have reached a length of more than 20 meters.

The largest complete fossil of ichthyologists ever discovered, measuring 3.5 meters tall, still contained a fetus in the womb.

Scientists said in August 2017 that the incomplete embryo was less than seven centimeters long and consisted of preserved vertebrae, a front fin, ribs and a few other bones.

There was evidence that the fetus was still developing in the womb when he died.

The find added to evidence that ichthyosaurs gave birth to live young, unlike egg-laying dinosaurs.