Triassic Period, c.250 million years BP. Aplete fossil Keichoaur hui in a veined rectangular matrix. 2.8 kg, 29cm wide (11 1/2"). From Xingyi, Guizhou, China. Acquired 1970s-1980s. Old Lincoln palaeontological collection. Keichoaur was a late-Triassic marine reptile, and a member of the Pleurosaur family, and became extinct 250 million years ago during the Triassic-Jurassic extinction event. They were specialised fish eaters, and were highly unual amongst marine reptiles in that they gave birth to live young rather than laying eggs.