A new genus and species of plesiosaur that lived near the beginning of the Epoch Epoch. Early to mid-Jurassic sales It was identified from two elaborate three-dimensionally preserved skeletons discovered in Bavaria, Germany.
Franconiasaurus brevispinus It lived in the early Jurassic seas about 175 million years ago.
The ancient reptile was a member of plesiosaurinaea group of plesiosaurs known from the Jurassic and Cretaceous periods.
“Plesiosaurs are Mesozoic reptiles perfectly adapted to aquatic life.” sven sachs From the Bielefeld Nature Museum and colleagues.
“Throughout an evolutionary history of more than 140 million years, plesiosaurs have dispersed throughout the world, acquired substantial diversity, occupied a variety of ecological niches, and experienced multiple faunal shifts. did.”
“Of these, the Early/Middle Jurassic transition event (175 to 171 million years ago) has received increased interest recently, as it apparently had a profound impact on all three major lineages of plesiosaurs. I am. Romareosauridae, Pliosauridae and plesiosaurinae. ”
“This event clearly had a significant impact on several clades of marine tetrapods, including the 'fish-like' ichthyosaurs, which are relatives of marine crocodiles.Taratoskian), as well as all three major lineages of plesiosaurs. ”
“The predatory plesiosaur clade Romareosauridae, which was dominant in the Early Jurassic seas, began to disappear and reached its final demise around 161.5 million years ago (late Middle Jurassic), while the pliosaurids and chief… The dragon family has become more diverse.”
“Pliosaurs established a successful clade of large predators that controlled the upper layers of marine ecosystems from 171 million years ago to 90 million years ago, making them one of the largest aquatic predators to ever live. It consisted of a predatory quadrupedal animal that was over 10 meters long.
“Plesiosaurs were then derived from the rich assemblages of microclades common in the European euoceanic waters of Toarchia to the cryptocliids, which represented the globally dominant plesiosaur component of the Middle and Late Jurassic. Switched to fauna. Leptocraidian and elasmosaurids Close to the transition period from the Jurassic to the Cretaceous. ”
Diagnostic skeletal elements of type specimens Franconiasaurus brevispinus.Image credit: Sax other., doi: 10.3389/feart.2024.1341470.
two fossilized skeletons Franconiasaurus brevispinus It was discovered in a now abandoned clay pit in a part of the eurensis melgel layerlocated in Mistelgau, Bavaria, Germany.
“Franconiasaurus brevispinus has been established on the basis of two exquisite three-dimensionally preserved specimens,” said the paleontologist.
“The holotype contains a nearly complete skeleton, but a large portion of the skull is missing.”
“The specimen mentioned represents a larger individual and consists of vertebrae, ribs, and some girdle and limb elements.”
Franconiasaurus brevispinus shows a mixture of characters that combines features that are almost uniformly distributed in early plesiosaurs with features that are typically observed in later members of the clade.
“Through systematic analysis, we can reliably Franconiasaurus brevispinus as a sister taxon of Cryptocridiabridging the evolutionary gap between early plesiosaurs such as plesiosaurus“They are representative forms of later-divergent clades such as cryptocliids, leptochleidians, elasmosaurids, and microclades,” the researchers concluded.
their paper Published in an online journal Frontiers of Earth Science.
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sven sachs other. 2024. Elaborate skeleton of new transitional plesiosaur fills a gap in plesiosaur evolutionary history. front.earth science 12; doi: 10.3389/feart.2024.1341470
Source: www.sci.news
