7.2K views · 297 reactions | Meet the Glaucus atlanticus This is a species of small, blue sea slug, a pelagic aeolid nudibranch, a shell-less gastropod mollusk in the family Glaucidae. These sea slugs are pelagic; they float upside down by using the surface tension of the water to stay up, where they are carried along by the winds and ocean currents Aloha! www.oceandefenderadventures.com | OCEAN DEFENDER - Hawaii | Facebook