US paleontologists have described a new genus and species of extinct crocodile relative based on a partially articulated skeleton found in the Middle Triassic Fossil Hill Formation of the Fabre Formation in Nevada, a pelagic region of the eastern Panthalasan Ocean rich in ammonites and giant ichthyosaurs.
Newly identified species Pseudobranchial reptiles It lived during the Middle Triassic period, between 247.2 million and 237 million years ago.
Named Bengwigiwishingasucus Elemical MinisThe animal probably reached a length of around 1.5-1.8 metres (5-6 feet).
It probably stayed fairly close to shore. Its limbs are well developed and well preserved, with no signs of aquatic life such as fins or changes in bone density.
“This intriguing new species provides evidence that pseudobranchs occupied coastal habitats worldwide during the Middle Triassic,” said Dr. Nate Smith, Gretchen Augustine Director and Curator of the Dinosaur Institute at the Natural History Museum of Los Angeles County.
“The area containing the Fabre Formation, which captured fossil life from the Triassic Eastern Panthalassa Ocean, is known for the fossils of marine creatures such as ammonites, as well as marine reptiles such as giant ichthyosaurs. Cymbospondylus youngholm — Newly written Bengwigiwishingasucus Elemical Minis It was a bit of a shock.”
“Our first reaction was, ‘What is this?'” said Dr Nicole Klein, a paleontologist at the University of Bonn.
“We expected to find something like a marine reptile. We couldn’t understand how a land animal could be so far out in the ocean amongst ichthyosaurs and ammonites.”
“It wasn’t until I actually saw the almost perfectly prepared specimen that I was convinced it was indeed a land animal.”
Although pseudopterygian archosaurs have been unearthed from coastal fossil beds in the Tethys Ocean, this is the first to be found in the Panthalassa Ocean and along the coasts of the Western Hemisphere, revealing that close relatives of these crocodiles were present in coastal environments worldwide during the Middle Triassic.
Interestingly, these coastal species do not all belong to the same evolutionary group, suggesting that Pseudobranchia (and Archosaurs more broadly) were uniquely adapted to life along the coast.
“Essentially, it seems like a very different group of archosaurs came together in the Middle Triassic and decided to dip their toes in the water,” Dr Smith said.
“What’s interesting is that many of these ‘independent experiments’ don’t seem to have led to a wider spread of semi-aquatic groups.”
Archosaurs appeared in the Triassic Period and split into two groups, with two representative species surviving: birds, which were descendants of dinosaurs, and pseudo-crocodile archosaurs such as crocodiles (alligators, crocodiles, and gharials). Bengwigiwishingasucus Elemical Minis.
Today’s crocodiles are similar enough to mistake them for other reptiles, but ancient species of crocodiles differed greatly in size and lifestyle.
Evolutionary relationships Bengwigiwishingasucus Elemical Minis and its relatives suggest that pseudobranchs gained great diversity very rapidly after the end-Permian mass extinction, but the extent of this remains to be elucidated in the fossil record.
“The recent and growing number of discoveries of Middle Triassic pseudobranchs suggests that there was underappreciated morphological and ecological diversity and experimentation taking place early in the group’s history,” Dr Smith said.
“Much of the public interest in the Triassic has been focused on the origin of the dinosaurs, but it was the pseudobranchs at the beginning of the Mesozoic that were actually doing interesting things.”
Discovery Bengwigiwishingasucus Elemical Minis It has been reported paper In the journal Biology Letters.
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Nathan D. Smith others2024. A new pseudobranch discovered in Nevada’s Fabre Formation indicates that archosaurs inhabited coastal regions around the world during the Middle Triassic. violet 20(7); Source: http://www.doi.gov/doi/2020240136 Source: 10.1098/rsbl.2024.0136
This article is based on a press release from the Natural History Museum of Los Angeles County.
Source: www.sci.news
