Chinese fossil may be earliest amphibian known to have lived fully at sea

A newly studied fossil named Gerrothorax maritimus suggests some ancient amphibians spent their entire lives in ocean environments. The creature lived roughly 237 million years ago and had a flattened body protected by bony armour. Its remains were recovered from deep-sea sediments, pointing to a habitat far from any landmass. Geochemical analysis of strontium isotopes in the fossil matched seawater from the Late Triassic period, supporting a marine origin.