Labyrinthodonts (image) Samara Polytech (Samara State Technical University) Share Print E-Mail Caption Labyrinthodonts are an extinct subclass of amphibians, the majority of which lived on the Earth in the Paleozoic and Mesozoic eras (390-150 million years ago). These are the ancestors of all modern mammals, from mice to elephants. Credit @SamaraPolytech Usage Restrictions This image may only be used with the credit @SamaraPolytech. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.