BBC NEWS | Science/Nature | Ancient fossil penis discovered The ostracode's appendages suggest that it swam and scavenged for food along the ocean floor. It was also definitely male as it has the oldest known example of a penis. The scientists say that the five-millimetre-long fossil is remarkably similar to some modern ostracodes, suggesting an extremely low rate of evolutionary change over the last 425 million years. As the discoverer of a new species, David Siveter and his co-researchers provided the name for the ostracode. They have called it Colymbosathon ecplecticos, which means "amazing swimmer with a large penis".