<I>Holoptychius</I> Lower Jaw Fossil (IMAGE) Drexel University Caption Dr. Ted Daeschler handles a lower jaw fossil from Holoptychius bergmanni, a lobe-finned fish species from the Devonian Period that he co-discovered and described. Credit Drexel University Usage Restrictions None License Licensed content 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.