The Blue Dragon (Glaucus atlanticus) is one of the world’s rarest and most beautiful mollusks. The normal size of this species is up to about 3 cm, depending on the animal's age. It is silvery grey on its dorsal side and dark and pale blue ventrally. It has dark blue stripes on its face. It has a tapering body which is flattened and has six appendages which branch out into rayed cerata. Its radula bears serrated teeth on their blades.The Blue Dragon is distributed throughout the world's oceans, in temperate and tropical waters. Regions where this slug is found include the East and South Coast of South Africa, European waters, the east coast of Australia and Mozambique. This species floats upside down on the surface tension of the ocean.
Atlanticus preys on other, larger pelagic organisms: the dangerously venomous Portuguese Man o' War Physalia physalis; the by-the-wind-sailor Velella velella; the blue button Porpita porpita; and the violet snail, Janthina janthina. Occasionally, individual Glaucus become cannibals given the opportunity.
