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.
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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
