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A small blue snail with a firm bubble-like body. It was flushed up on the beach and seemed to be alive.
Beach of Indian Ocean
The violet snail is a marine gastropod that spends its whole life drifting on the ocean surface in warm seas, floating on a bubble raft of its own making. It feeds on jellyfish, such as the By-the-wind-sailor, Velalla velalla, or the Portuguese man-o-war, Physalia physalis. It starts life as a male and becomes female over time. The violet snail, Janthina janthina, also known as the violet shell snail and purple bubble raft snail, is holopelagic, meaning it spends its entire life cycle on the open sea. It secrets mucus from its foot which binds bubbles together in a raft, on which it floats freely on the ocean, in equatorial and temperate waters. Its shell is 3-4 cm in size, light and fragile, and is a dark purple at the widest part, fading to a light purple at the narrow top. Its body ranges from dark purple to black. Violet snails are protandric hermaphrodites, meaning they are born male and develop into females over time. Fertilization is internal, but males lack a penis, so there is no direct mating. Instead, the males release their sperm into a case that drifts to a female, where the sperm fertilizes the eggs. The eggs develop internally and are born live, with the tiny purple snails immediately able to build their own rafts. They use their feet to agitate the water, creating bubbles, which they bind together with mucus. If the bubble raft ever breaks apart, the snail will sink into the ocean and die. Violet snails are preyed upon by fish, birds, sea turtles, other molluscs and nudibranchs. The snails sometimes have pelagic barnacles attached to their shell as hitchhikers. Taxonomically, violet snails are classified as Phylum Mollusca, Class Gastropoda, Order Neotaenioglossa, Family Janthinidae, Genus Janthina, Species Janthina janthina.