A sensational smooth swimmer. This is Enypniastes eximia, a species of sea cucumber. It is the only one in its genus, making them unique among sea stars and urchins, their squishy-bodied relatives. While most of these creatures spend the majority of their lives scooping and pooping sediment on the seafloor, Enypniastes can swim. With webbed structures at the front and back of their bodies that act like fins, they can lift off the seafloor and swim up to 1,000 meters into the water column, accord