Purple Sea Snail, Violet Snail
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Epitoniidae (formerly Janthinidae), Genus: Janthina, Species: Janthina janthina · Epitoniidae (Wentletrap family) / Janthinidae (Violet snail group) · Gastropod (univalve); spiral, globose-conical shape.
Species
Janthina janthina
Shell Type
Gastropod (univalve); spiral, globose-conical shape.
Family
Epitoniidae (Wentletrap family) / Janthinidae (Violet snail group)
Size
Approximately 15-20mm (0.6-0.8 inches). Typical adult range is 10-40mm.
Color & Pattern
Striking bicolored appearance with deep violet on the base and lighter lavender-white on the spire. This is a form of counter-shading.
Rarity
Uncommon to Rare on beaches; usually found only after specific wind and current events ("blue fleet" wash-ups).
Habitat
Pelagic; lives floating at the ocean surface in tropical and warm temperate waters using a bubble raft.
Geographic Range
Worldwide in tropical and subtropical oceans; often wash ashore after storms in the Atlantic, Pacific, and Indian Oceans.
Description
A lightweight, fragile shell with a short spire and large body whorl. The shell is thin and translucent, lacking a heavy columella or operculum to facilitate buoyancy.
Key Features
Thin, paper-like shell wall; distinct purple gradient; lacks an operculum; reversed color pattern compared to bottom-dwelling snails.
Collector Value
Moderately high for beachcombers due to its fragility and pelagic nature. Larger, perfectly intact specimens can be prized additions to a collection.
Condition Notes
Good; shows solid color but has some slight beach-wear on the apex. Extremely fragile, making intact beach specimens highly desirable.
Interesting Facts
The snail creates a 'bubble raft' by trapping air in mucus with its foot. It is a specialized predator of siphonophores like the Portuguese Man o' War.
Ecological Role
Specialized surface predator that helps control populations of floating hydrozoans; highly sensitive to ocean temperature changes.
Similar Species
Janthina globosa (rounder with a shorter spire) and Janthina pallida (paler, more globose).
Beach Finding Tips
Look for them after strong onshore winds (blows) alongside other 'blue fleet' organisms like Velella velella or Man o' War.