Triassic Period, 250-200 million years BP. A complete fossil Keichousaurus hui from Xingyi, Guizhou, China on matrix. 717 grams, 27.5cm (10 3/4"). From an old Bristol paleontological collection; acquired 1950s-1960s. Keichousaurus was a late-Triassic marine reptile, and a member of the Pleurosaur family, which went extinct 250 million years ago during the Triassic-Jurassic extinction event. They were specialised fish eaters, and were highly unusual amongst marine reptiles in that they gave birth to live young rather than laying eggs. Fine condition.