Two skeletons in China reveal the first amphibian that lived its whole life in the sea

Amphibians breathe and drink through their skin — wonderful in a pond, ruinous in salt water, which is why no amphibian, living or extinct, was ever known to be fully marine. Until now. In rocks in China's Guizhou Province, researchers found two nearly complete skeletons of a creature that lived about 237 million years ago, before the dinosaurs: Gerrothorax maritimus, about 75 centimetres (30 inches) long, flat and armoured like a living shield, with a wide mouth built for ambushing prey by suction from the sea floor. Its bones carry the chemical signature of Triassic seawater, showing it grew up in the ocean alongside the great marine reptiles of its day. 'Very odd and charming in its own way,' said palaeobiologist Ryosuke Motani of the University of California, Davis, one of the study's leaders, in the paper published in Nature Ecology & Evolution.