Two nearly complete fossil skeletons of Gerrothorax maritimus, described as the first known fully marine stem amphibian, were discovered in Guizhou Province, China.
Lived about 237 million years ago during the Late Triassic period of the Mesozoic Era.
It belonged to Temnospondyli, an extinct group of early four-limbed vertebrates related to the amphibian evolutionary lineage.
The species was named Gerrothorax maritimus; “maritimus” refers to its marine habitat.