Nothosaurus giganteus is one of the largest species of Nothosaurus, a genus of semi-aquatic reptile in the family Nothosauridae. This genus originally lived during the Triassic period, between 240 and 210 million years ago, and fossil remains are widespread in Africa and Eurasia. The species N. giganteus in particular is known to have inhabited what is now Osnabrück, Germany.
