Plesiosaurs were a type of carnivorous sea reptiles. First plesiosaurs appeared in Triassic and last died at the end of Cretaceous. Like pterosaurs and mosasaurs, plesiosaurs lived in same time with dinosaurs, but weren't dinosaurs although. The order Plesiosauria was represented by long-necked Plesiosauroidea and short-neck Pliosauroidea.
In PrimevalLiopleurodon, a huge Pliosaur came trough an anomaly in the Spaghetti Junction on Guns Island. It's attack trawler in the Atlantic Ocean. It's last encountered by ARC team and died from the cold conditions of the Atlantic winter.
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