Arctacellularia tetragonala (IMAGE) University of Liège Caption Microphotograph of the fossil Arctacellularia tetragonala, one of the first unambiguous fossils of photosynthetic eukaryotes. Credit @MC Sforna / University of Liège Usage Restrictions Credit mention License Original 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.