A second two-meter-long ichthyosaur jawbone discovered in Somerset, UK, has unveiled a new giant species, Ichthyotitan severnensis, dating back 202 million years, adding significant insight into Triassic marine giants. A washed-up Ichthyotitan severnensis carcass on the beach. Credit: Sergey Krasovskiy, CC-BY 4.0
The fossilised remains of a second gigantic jawbone measuring more than two metres long has been found on a beach in Somerset, UK.
Experts have identified the bones as belonging to the jaws of a new
Photograph of the nearly complete giant jawbone, along with a comparison with the 2018 bone (middle and bottom) found by Paul de la Salle. Credit: Dr Dean Lomax
Realising they had discovered something significant, they contacted leading ichthyosaur expert, Dr. Dean Lomax, a paleontologist at The University of Manchester. Dr Lomax, who is also an 1851 Research Fellow at the
A giant pair of swimming Ichthyotitan severnensis. Credit: Gabriel Ugueto, CC-BY 4.0
The last piece of bone was recovered in October 2022.
The research team, led by Dr Lomax, revealed that the jaw bones belong to a new species of giant ichthyosaur that would have been about the size of a blue whale. Comparing the two examples of the same bone with the same unique features from the same geologic time zone supports their identifications.
The team has called the new genus and species Ichthyotitan severnensis, meaning “giant fish lizard of the Severn.”
Historical Context and Significance
The bones are around 202 million years old, dating to the end of the
Part of the research team in 2020 examining the initial finds (at the back) of the new discovery made by Ruby and Justin Reynolds. Additional sections of the bone were subsequently discovered. From left to right, Dr Dean Lomax, Ruby Reynolds, Justin Reynolds, and Paul de la Salle. Credit: Dr Dean Lomax
Dr Lomax added: “I was highly impressed that Ruby and Justin correctly identified the discovery as another enormous jawbone from an ichthyosaur. They recognized that it matched the one we described in 2018. I asked them whether they would like to join my team to study and describe this fossil, including naming it. They jumped at the chance. For Ruby, especially, she is now a published scientist who not only found but also helped to name a type of gigantic prehistoric reptile. There are probably not many 15-year-olds who can say that! A Mary Anning in the making, perhaps.”
Ruby said: “It was so cool to discover part of this gigantic ichthyosaur. I am very proud to have played a part in a scientific discovery like this.”
Further examinations of the bones’ internal structures have been carried out by master’s student, Marcello Perillo, from the University of Bonn, Germany. His work confirmed the ichthyosaur origin of the bones and revealed that the animal was still growing at the time of death.
He said: “We could confirm the unique set of histological characters typical of giant ichthyosaur lower jaws: the anomalous periosteal growth of these bones hints at yet-to-be-understood bone developmental strategies, now lost in the deep time, that likely allowed late Triassic ichthyosaurs to reach the known biological limits of DOI: 10.1371/journal.pone.0300289