Museum-quality cast of Mesosaur Fossil Species: Mesosaurus brazialiensis Permian Period Approx. 260 million years Irati Formation Sao Paulo, Brazil This high quality cast replica was carefully produced from a mold of a beautifully preserved prehistoric reptile called a mesosaur. Although superficially resembling small plesiosaurs, mesosaurs were a separate group of aquatic reptiles that lived during the Permian period--before dinosaurs appeared on earth. They were probably fast swimming, fresh-water predators which preyed on small fish and aquatic invertebrates. This cast is composed of high-strength gypsum cement and was meticulously hand-painted to faithfully reproduce the colors and finest details of the original specimen.