Triassic Period, 250 million years BP. A complete fossil Keichousaurus hui skeleton in a rectangular matrix. 1.9 kg, 33.5cm (13 1/4"). From an old Bristol paleontological collection; acquired in the 1950s-60s; from Xingyi, Guizhou, China. Keichousaurus was a late-Triassic marine reptile, and a member of the Pleurosaur family, and 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.