In May 2020 while searching for fossils on a
beach in Devon
, southwest England, a father and 11-year-old daughter found remains of
a 2-meter jaw
that turned out to be similar to others found in 2016 and belong to
a new type. marine reptile
,
the largest known so far
.
Eight years of work by researchers from the University of Bristol and the University of Manchester have culminated in the description of a hitherto unknown species, which they have named
giant ichthyosaur ('Ichthyotitan severnensis')
, which means "giant fish lizard" for its size of more than 25 meters.
The discovery, now published in the journal Plos One, speaks of a species
similar in appearance to today's dolphins
but in a giant version - twice the size of a line collective - that lived in the Upper Triassic, in a time known as the Rhaetian.
Analysis of the internal structures of the bones of the last jaw found confirmed that they belong to an ichthyosaur and revealed that the animal
was still growing at the time of its death
.
The bones date specifically from
202 million years
ago , at the end of the Triassic period, when gigantic ichthyosaurs swam through the seas while dinosaurs walked on land.
Although other species of ichthyosaurs continued to inhabit the oceans for more years, researchers believe that their most giant version became extinct during the Triassic-Jurassic period 200 million years ago, and this unique group of marine reptiles never reached such a large size again. which is also similar to that of a blue whale.
The rocks in which the fossils have been found indicate "that a cataclysm would have caused a global mass extinction of the Late Triassic, which would have wiped out these giant marine reptiles."
These two bones appear about 13 million years after their most recent geological relatives, Shonisaurus sikanniensis from British Columbia (Canada) and Himalayasaurus tibetensis from Tibet (China).
How was the discovery?
The first jaw remains of a giant ichthyosaur were found in 2016 near Lilstock beach, southwest of England, by researcher Paul de la Salle, and described in 2018 in research led by ichthyosaur paleontologist Dean Lomax. from the University of Manchester, also author of the present study.
In 2020, while visiting the site,
Justin Reynolds and his
11-year-old daughter Rubi discovered remains of a new jaw on Brauton beach, a town near Lilstock, where the first one was found.
"In 2018 my team had described the giant jaw found by Paul de La Salle in 2016, and we 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 giant bones
- called surangulars - that have a unique shape and structure," explains Lomax.
The paleontologist admits that he was very surprised when Justin and his daughter Rubi "recognized that the jaw found coincided with the one found in 2016" and contacted him.
"I asked them (the girl) if they would like to join my team to study and describe this fossil, including naming it, and they jumped at the opportunity."
Rubi, now 15 years old, is one of the authors of the present study:
"She is a potential Mary Anning
," says Lomax, referring to the 19th century British paleontologist, author of important discoveries on the seabeds of the Jurassic period.
"These jaws are tantalizing evidence that one day we may find a skull or a complete skeleton of one of these giants. You never know," Lomax concludes.
The fossil remains of the new giant marine reptile will soon go on display at the Bristol Museum and Art Gallery.
With information from EFE
D.D.