Produced by the Population Genetics and Evolution class, Furman University

The Carboniferous: Anthracosaurs
Anthracosaurs were one of the first groups of tetrapods to colonize the land. They were descended from aquatic tetrapods that walked at the bottom of rivers and swamps. These tetrapods split into the aquatic or semi-aquatic ancestor of modern amphibians and the terrestrial anthracosaurs (Cofrin Center for Biodiversity 2004). The anthracosaurs were a group of labyrinthodont amphibians with a long, eel-like body and a deep skull. The less sprawling body plan gave them increased agility (Hoe et al. 1996).
The adaptation of having an amniotic shell is very important for terrestrial life and it seems that anthracosaurs might be an early ancestor of the amniotes because of structural similarities with later amniotes (Carroll 2001). However, the lack of evidence makes classification of anthracosaurs difficult and impedes our ability to understand the relationship between antracosaurs and amniotes (Carroll 2001).

Page by Laura Snyder
Proterogyrinus, an Anthracosaur. From: Wikipedia

Hoe A, Jusay A, Mayberry R, Yu C. 1996. Life of the carboniferous. University of California Museum of Paleontology. Accessed March 4, 2010. Available from:

Carroll RL. 2001. The origin and early radiation of terrestrial vertebrates. J Paleontol. 75:1202-1213.

Cofrin Center for Biodiversity. 2004. Amphibians and Reptiles. University of Wisconsin-Greenbay. Accessed March 4, 2010.