English: greererpeton burkemorani 01 - Cleveland Museum of Natural History - 2014-12-26

Greererpeton burckemorani is an extinct amphibian that lived about 335 to 331 million years ago.

It's a tetrapod, a four-limbed animal. Fishes were the first animals to evolve on Earth, and the lobe-finned fishes evolved into tetrapods. Tetrapods today involve everything from birds to dogs to frogs to lizards. Even human beings.

This fossil was the first ever unearthed. It was discovered by William E. Moran and Cleveland Museum of Natural History paleontologists John J. Burke in 1969 in the Greer Quarry at Greer, West Virginia.

Greererpeton was just under 5 feet in length, and had an elongated, eel-like body which gave it exceptionally good swimming abilities. Its skull, just 7 inches long, was flat and full of teeth for eating fish. The tail was long and upright, like a paddle. Marks on the skull indicate it had a "lateral line", an organ common in fish which allowed it sense vibration in the water and hunt prey.

Indications are that Greererpeton was a primitive amphibian which lived in rivers and swamps. Its small, relatively undeveloped limbs indicate it rarely, if ever, ventured on land.