Bone belongs to reptile ‘the size of blue whale’

A 205-million-year-old bone discovered in the UK belonged to a sea reptile approaching the size of a blue whale, according to experts.

The jaw bone, found on the beach at Lilstock in Somerset, has been identified as that of a giant ichthyosaur.

It could have measured up to 26m in length and be one of the largest ichthyosaurs ever known, according to a study published in journal PLOS ONE.

The largest reported ichthyosaurs – the shastasaurid – lived during the late Triassic period, around 200 to 235 million years ago, and ranged from 6m to more than 20m long.

Paul de la Salle, a fossil collector and co-author of the study, discovered the jawbone in May 2016.

“Initially the bone just looked like a piece of rock but, after recognising a groove and bone structure, I thought it might be part of a jaw from an ichthyosaur,” he said.

He later returned and found more pieces measuring around one metre in length.

The specimen was identified 0 The shonisaurus is the largest known ichthyosaur as an incomplete bone, known as a surangular, from the lower jaw of an ichthyosaur by experts Dean Lomax, of the University of Manchester, and Professor Judy Massare of Brockport College, New York.

They found similarities with the shastasaurid Shonisaurus sikanniensis, the largest known ichthyosaur at 21m long, indicating the bone belonged to a similar species.

Mr Lomax said: “As the specimen is represented only by a large piece of jaw, it is difficult to provide a size estimate, but by using a simple scaling factor and comparing the same bone in Shonisaurus sikanniensis, the Lilstock specimen is about 25 per cent larger.”