STORY: This jawbone fossil found by a British father-daughter duo belonged to perhaps the largest-known marine reptile on Earth - dating back to around 202 million years ago.
Ruby and Justin Reynolds found the bone in May 2020 on a beach in Somerset, England.
They contacted paleontologist Dean Lomax who said four years before their discovery, fossil hunter Paul de la Salle found a similar bone just down the coast.
"We described Paul's bone in 2018 in a study as an unusual giant jawbone, part of a surangular from right at the back of the jaw of an ichthyosaur."
Researchers said on Wednesday (April 17) the Reynolds' bone is also from an ichthyosaur.
The discovery of a second jawbone confirms the existence of a new species not previously known.
"Based on that unique shape, various different structures, the fact that they are both right from the end of the Triassic period, about 202 million years ago, supports our identification of something entirely new to science, which we've named as a new species called Ichthyotitan severnensis."
The ichthyotitan severnensis was between 72 and 85 feet long.
That means it would rival the largest animal to ever exist, the blue whale, which can reach up to 100 feet long.
"No other marine reptiles got as large as these animals did."
The giant marine reptile lived 13 million years later than any others known to date.
Researchers believe they could have survived until a global mass extinction event about 201 million years ago.
"It's quite remarkable to think that gigantic blue whale-sized ichthyosaurs were swimming in the oceans around the time the dinosaurs were walking on land in what is now the UK during the Triassic period. These jawbones provide tantalizing evidence that perhaps one day, fingers crossed, a complete skull or a skeleton might be found. You never know."
