A 425-Million-Year-Old Parasite (IMAGE) University of Leicester Caption A 425-million-year-old parasite: the pentastomid Invavita piratica (in orange) attached externally to the shell of its host (an ostracod). The ostracod is using its limbs to swim forward. Credit Image credit: Siveter, Briggs, Siveter and Sutton 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.