This Armored Amphibian Turned the Triassic Seafloor Into a Living Nightmare

Key Points:

• Researchers have described Gerrothorax maritimus, an ancient amphibian from the Late Triassic period (about 237 million years ago), notable for being the first known amphibian fully adapted to life in salty ocean water.
• The nearly complete skeletons, found in southwestern China, suggest the amphibian was about 30 inches long and likely used suction feeding to capture prey on the seafloor, similar to modern suction-feeding sharks.
• Evidence supporting its marine lifestyle includes well-preserved fingers and strontium isotope ratios in the bones and sediments, indicating the animal lived and grew in the sea rather than being transported post-mortem.
• Unlike modern amphibians with permeable skin that limits saltwater tolerance, G. maritimus had bony armor protecting its skin and retained gills into adulthood, allowing it to breathe underwater and thrive in a marine environment.
• Further research aims to uncover additional specimens to better understand its physiology, ecology, and reproductive adaptations to saltwater life.