Paleontologists have described Gerrothorax maritimus from two nearly complete skeletons in marine sediment in China. The animal lived about 237 million years ago, was roughly 75 centimeters long and had a broad, armored, flattened body.
Its anatomy suggests a seafloor ambush predator that could suction-feed on passing animals. The intriguing hypothesis is that armor evolved for defense may also have helped its permeable amphibian skin cope with seawater. Chemical signals in the fossils support a genuinely marine life rather than a freshwater animal washed into ocean sediment.
This is an enjoyable science detour: the story illustrates how an evolutionary feature can be repurposed. Read the reporting and follow its study reference if the anatomy catches your interest.
Go to Source — [www.reuters.com](https://www.reuters.com/business/environment/ancient-armored-bottom-feeder-is-first-seagoing-amphibian-2026-10-27/) https://www.reuters.com/business/environment/ancient-armored-bottom-feeder-is-first-seagoing-amphibian-2026-10-27/