Tag Archives: plesiosaur

Discovery of a new species of plesiosaur in Germany

Posted on by
Reply

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.

rebuilding the life of Franconiasaurus brevispinus. Image credit: Joschua Knüppe.

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.

_____

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

Confirmation of a new species of plesiosaur found in the United States

Posted on by
Reply

Paleontologists have described a new genus and species of small polycotyledonous plesiosaur from two specimens discovered in the US states of Wyoming and South Dakota.

rebuilding the life of Untahira Specta The proposed habitat is a sunlit body of water just below the earth's surface, and the eyes are covered by bulges above the orbits.Image credit: Clark other., doi: 10.1016/j.cretres.2023.105812.

Untahira Specta lived in the waters of Western Inland Sea Route Late Cretaceous period, approximately 80.5 million years ago.

This marine reptile is polycotyledonous plantsa family of plesiosaurs that evolved in the Early Cretaceous and radiated into multiple genera in the Late Cretaceous.

“Polycotyledons were a marine herpeta superfamily of the Cretaceous period. plesiosaurinae” said the lead author. Dr. Robert Clark and colleagues at Marshall University.

“The earliest polysperms are known from the Aptians of Australia, but they reached North America by the Albians and achieved an international distribution before dying out along with the rest of the polysperms. plesiosaur At the end of the Maastrichtian. ”

“Polysosaurs had short tails, limbs transformed into large paddles, and plesiosaur-like bowplans of broad, hydrodynamic bodies with extended pectoral and pelvic girdle, but short It also had a derivative condition: a large head with a neck and an elongated snout.”

“It has converged, but Pliosauridae In these traits, the small clefts and teeth of most polycots indicate that they occupied different ecological niches. ”

holotype of Untahira Specta.Image credit: Clark other., doi: 10.1016/j.cretres.2023.105812.

Two fossilized skulls (holotype and paratype) Untahira Specta Recovered from the Baculites obtusus zone of the Sharon Springs Formation in the United States.

“The holotype is a skull and mandible with an almost complete cervical, sacral, caudal series, partial dorsal series, ribs, part of the pelvic and pectoral girdle, both iliac bones, both anterior paddles, both It has a rear paddle,” the paleontologists said. Said.

“The paratype is a complete cranium, a three-part lower jaw, and five small, fragmentary, unidentified postcranial elements.”

Untahira Specta It was a small polycotyledonous plant, 2.3–2.6 m (7.5–8.5 ft) long, with a broad skull and distinctive paddle.

The large eyes had flat protuberances that probably blocked sunlight. It is possible that they were visually chasing prey just below the water surface.

“Comparisons with extant quadrupeds suggest several characteristics of quadrupeds. Untahira Specta “This may be an adaptation to predation by visual tracking in sunny environments, an interpretation with ecological implications for other aquatic reptiles,” the researchers said.

their findings It was published in the magazine Cretaceous research.

_____

Robert O. Clark other.Elucidation of a new genus of small polycotyledonous plesiosaurs that lived in the Upper Cretaceous of the Western Interior Seaway and its genus doricorinchops. Cretaceous research, published online on December 24, 2023. doi: 10.1016/j.cretres.2023.105812

Source: www.sci.news