This skeleton was found in China in 2004. Scientist finally know what it is

Key Points:

• A new species of stem amphibian, Gerrothorax maritimus, discovered in Late Triassic rocks in China, challenges the belief that amphibians never adapted to fully marine lifestyles.
• Unlike modern amphibians, which are salt-intolerant due to their skin-based respiration, G. maritimus had internal gills and body armor that likely limited salt and water exchange, enabling it to live in seawater.
• Chemical analysis of the fossils and their location in marine deposits about 30 km from land indicate G. maritimus was well-adapted to a marine environment, making it the first amphibian found in a fully marine setting.
• The species' large mouth suggests it was a bottom suction feeder, similar to modern wobbegong sharks, though many physiological details remain unknown due to lack of soft tissue preservation.
• This discovery expands understanding of amphibian evolution, showing that some stem amphibians colonized the sea, a feat no modern amphibians have achieved.