Fossil Holotype (Retrophyllum oxyphyllum, comb. nov.) (IMAGE) Pensoft Publishers Caption The holotype of the species Retrophyllum oxyphyllum (comb. nov.), previously thought to be the oldest known bamboo. Credit Peter Wilf Usage Restrictions CC-BY 4.0 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.