From their mesmerizing violet hue to their impressive bubble-making abilities, violet sea snails are truly a wonder of the ocean. These tiny creatures have a big impact, both in terms of their ecological importance and their unique adaptations for survival. So come dive into the depths and explore the facts of these purple mystery snails.
Phylum: Chordata
Class: Gastropoda
Family: Epitoniidae
Genus: Janthina
1. They’re purple from inside to outside
While walking along the seashore, you may find a distinctive purple shell among the assortment of debris, seaweed, and shells. Despite resembling a garden snail, this shell stands out due to its exquisite violet hue and delicate structure.
This particular shell belongs to the violet sea snail, also known as the bubble raft shell, which is a type of marine gastropod mollusk. Unlike the garden snails, the violet snail’s conical-shaped shell is thinner and more fragile, helping the species live in the ocean. These small snails usually grow to be about the size of a dime.
As the name suggests, this snail is purple, from the inside to the outside. Its shell is composed of various shades of purple while its soft and fleshy body has a deep violet color.
Violet sea snails feature a lengthy, cylindrical snout as part of their head structure and no visible eyes. The adults don’t have the operculum and their body can reach a size of 4 cm. This body is covered by a delicate, see-through layer known as a mantle, which safeguards and hydrate their skin constantly.
Similar to other snails, the purple snail also features a set of tentacles on their head that it uses to detect its surroundings and locate prey.
2. Habitat
These purple sea snails live in both tropical and temperate oceans, including the Pacific, Atlantic, and Indian Oceans, as well as coastal waters worldwide.
These tiny creatures, measuring only 3 or 4cm in length, belong to the ‘Pleuston’ category of organisms that reside on the ocean’s surface. Despite their diminutive size, they’re one of the largest inhabitants of this thin yet vast habitat and play a significant role in it.
3. They use bubbles to move
As a snail, this creature has its own special method to live in the ocean. It creates a raft with self-made materials. The violet snail produces mucous from its foot gland. This mucous adhere to a chain of air bubbles formed when the snail agitates the water with its foot.
As this mixture hardens, it becomes a floating raft. The snail will attach itself to the raft and spend the rest of its life there, floating in the wide ocean. Being afloat on the surface of the ocean makes the species dependent on the influence of ocean currents and prevailing winds. This is why it can often be found washed up on the beach along with the Man O’ Wars.
One violet sea snail only creates a floating raft in its whole life. This means that if its raft breaks, it’ll die. The snail will sink into the seafloor and can’t generate another raft because it cannot create a string of bubbles here. Once stuck on the ocean bottom, violet sea snails will die quickly since they are not equipped to survive in the environment here.
4. Violet sea snails have great camouflage
To float in the ocean, violet sea snails will attach themselves to the bubble raft in the upside-down position. They don’t do this do fun! This gives them an excellent camouflage (known as countershading) to survive in the ocean full of dangers. The blue dragon sea slugs also apply this technique.
The snail’s upper side is a lighter violet, while its underside is dark violet. By hanging upside down, the violet globe snails create an illusion for their predators in the water that they are looking at the light-colored sky above. For predators in the air, they are fooled into thinking they’re looking at the deep blue sea below.
5. Diet
Violet sea snail Janthina feeds on organisms found in the neuston, such as the Portuguese man of war, blue button, and by-the-wind sailor. They also consume algae and other plant matter.
So, how can they eat these prey? When they come into contact with their victim, they use their radula (a file-like structure) to scrape away the soft tissue of the prey.
However, the Janthina is not exempt from becoming prey themselves. Their predators include fish, turtles, birds, mollusks, and nudibranchs. They can have little barnacles adhering to them from drifting in the sea.
6. Reproduction
One of the fascinating things about violet sea snails is their mating habits. These species are protandric hermaphrodites. They begin their life cycle as males and gradually transform into females as getting older.
These creatures are not capable of internal fertilization. The male’s penis is not developed enough for them to mate directly. Instead, they deposit their sperm into capsules that float to the female, enabling fertilization to take place within the females.
After fertilization, the female violet sea snails attach long, slender strands of eggs to floating objects. The females nurture their free-swimming larvae upon hatching before releasing them into the water.
The juvenile sea snails instantly start secreting mucus and creating bubbles to stay afloat in the water.
7. Threats
The survival of this sea snail is threatened by several factors, such as habitat loss, the impacts of climate change, and ocean acidification. These violet sea snails are also endangered by overfishing. Their shells are frequently harvested and utilized for decorative intentions.
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