Early croc and swamp signs.

name: proterogyrinus (pro-tuh-roe-gee-ree-nus) “early wanderer”
animal type: anthracosaur amphibian
size: 2.3 meters long
lived: Late Carboniferous 325 - 320 mya
diet: Carnivore
found: North America
fossil:

During the time period of the proterogyrinus, amphibians were an extremely diverse and exciting group of animals. They basically controlled the waterlogged forest areas and the proterogyrinus was one of the largest amphibians fully adapted for the life in the swamps. It could both hunt on land and in the water - it had powerful jaws and very sharp teeth that allowed to to hunt large animals both in and out of the water. It would have laid its eggs in water, but would have wandered into damp environments such as ponds and rivers to keep the eggs protected.

Most of the amphibians in the carboniferous period were really good swimmers and could move at great speeds through the waters but few actually made it onto the land. The proterogyrinus’ legs allowed it to catch food where its rivals couldn’t even dream of going. The biggest threats of the time were large water animals and sharks, thus its legs allowed it to seek refuge on shores and logs with ease where other amphibians couldn’t.

Proterogyrinus was an anthracosaur meaning that it belonged to a group of advanced amphibians known as reptilmorphs because it had reptilian characteristics. The amphibians that we have today would have evolved from the batrachomorphs who also lived in the carboniferous swamps. The largest amphibian on the fossil record was koolasuchus, by the start of the mezozoic era, 248 mya, the larger amphibian fossils were virtually unknown.