Eryops megacephalus was a large, semi-aquatic amphibian from the late Carboniferous to early Permian periods. It possessed a massive skull, sturdy limbs, and a sprawling gait, adapted for life both in water and on land. Its sharp teeth hinted at a carnivorous diet, preying on fish and smaller amphibians.

Eryops megacephalus is known from fossil records primarily in North America, specifically in what is now the southwestern United States. These fossils are predominantly found in the Permian strata of Texas and New Mexico.

During the Permian period, the regions where Eryops lived were characterized by a warm climate with seasonal variations. The environment likely included extensive floodplains, river systems, and swampy areas, which were conducive to the amphibious lifestyle of Eryops.

Eryops megacephalus inhabited freshwater environments, such as rivers and swamps, where it likely played the role of a top predator. Its robust body and large limbs suggest it was well-adapted for a semi-aquatic lifestyle, hunting fish and other aquatic organisms, as well as possibly venturing onto land to prey on smaller terrestrial animals.