The Reef Periwinkle is known for its bright blue color and the anemone that often grow on its shell. This creature is quite big in size and can reach up to 50 centimeters in length. Despite its unusually large size, they are incredibly friendly and only feed on algae.

There have been recent reports of Reef Periwinkles, among other types of Periwinkles, venturing in deeper waters than they are normally located. The inhabitants of local islands explain this by saying that they are searching for the Sunken Sea King, this is a big part of local folklore that describes sightings of an enormous crown near shipwrecks. A more scientific explanation for this mass migration is that much like ants, Periwinkles follow a pheromone trail left by other species of their kind, what is leaving this pheromone train remains unknown.