 Chaetopterus pugaporcinus

Chaetopterus pugaporcinus, commonly known as the pigbutt worm or flying buttocks, is a species of worm first described by scientists at the Monterey Bay Aquarium Research Institute in 2007.The worm is round in shape, approximately 10 to 20 millimeters in length (roughly the size of a hazelnut), and bears a strong resemblance to a disembodied pair of buttocks.