Triassic Period, 250 million years BP. A complete fossil Keichousaurus hui in a rectangular matrix. 1.5 kg, 33 x 22cm (13 x 8 1/2"). From an old Bristol palaeontological collection; acquired 1950s-1960s; 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.