2024-04-19 12:25:42
The newly discovered creature belongs to a group of ichthyosaurs, which were among the dominant marine predators during the Mesozoic Era (251.9-66 million years ago). The newly described species lived at the end of the Triassic period (251.9 million to 201.4 million years ago).
Ichthyosaurs already reached huge sizes at the beginning of the Mesozoic period – but the largest species did not appear until the end of the Triassic.
Although the Mesozoic is called the age of the dinosaurs, the ichthyosaurs themselves were not dinosaurs – they evolved from another group of reptiles. Their evolutionary path is very similar to that of whales, which evolved from land mammals that later returned to the sea. Like whales, they breathed air and gave birth to live young.
The newly discovered ichthyosaur species was excavated in parts between 2020 and 2022. Blue Anchor in Somerset, UK. The first piece of fossil was spotted on the beach on a rock. The researchers presented their findings on April 17. published in the journal PLOS One.
The remains of the reptile consist of 12 jaw bone fragments. Researchers estimated that the bone was 2 meters long, and the entire living animal was about 25 meters long.
Scientists named the sea monster Ichthyotitan severnensis, which means the giant Severn lizardfish, after the estuary of the River Severn where it was found. The research team believes that this is not only a new species, but also an entirely new genus of ichthyosaurs. More than 100 species of ichthyosaurs are already known.
Several rib fragments and coprolites (fossilized faeces) were also found at the site, but these were not definitively attributed to the same animal.
The sediments where the specimens were found contained rocks that showed earthquakes and tsunamis at the time, which the researchers say suggests the species lived during a period of intense volcanic activity that may have led to the mass extinction at the end of the Triassic.
A similar copy in 2016. was discovered in Lilstoke, Somerset, and described in 2018. Both were found in the so-called Westbury Formation, within 10 km of each other. This ichthyosaur is estimated to have been as long as 26m – although the authors of the latest study believe it was slightly smaller.
The previous contender for the title of largest marine reptile was another ichthyosaur – Shonisaurus sikanniensiswhose length reached up to 21 years. S. sikanniensis 13 million appeared. years earlier than I. severnensis and was found in British Columbia – making it unlikely that the new discovery is another specimen of a previously known species.
A similar massive ichthyosaur named Himalayasaurus tibetensis, which could reach 15 m in length, was discovered in Tibet and described in 1972. It dates back to the same period – which means it’s probably not the same species as the new discovery either.
Researchers say that I. severnensis was probably one of the last giant ichthyosaurs. Ichthyosaurs persisted through the Late Cretaceous (100.5–66 million years ago) to the Cenomanian (100.5–93.9 million years ago). They were eventually supplanted by plesiosaurs, long-necked marine reptiles that went extinct along with all non-avian dinosaurs at the end of the Cretaceous, according to Live Science.
2024-04-19 12:25:42