Violet Sea-snail Shell, Janthina janthina

Violet Sea-snail Shell, Janthina janthina. Shell collected at sea off the surface in the greater Los Cabos area, May 2018. Size: 2.0 cm (0.8 inches) x 1.5 cm (0.6 inches).

Violet Sea-snail Shell, Janthina janthina. Shells collected off the beach in the greater Los Barilles area, Baja California Sur, January 2024. Size: 1.8 cm (0.7 inches) to 2.0 cm (0.8 inches). Collections, photograph and identifications courtesy of Brad Murakami, Surrey, British Columbia.

Violet Sea-snail Shell, Janthina janthina. Shells collected off the beach in the greater Los Barilles area, Baja California Sur, January 2024. Size: 1.8 cm (0.7 inches) to 2.0 cm (0.8 inches). Collections, photograph and identifications courtesy of Lisa Alex, Sandy, Oregon.

The Violet Sea Snail, Janthina janthina (Linnaeus, 1758), is a gastropod mollusk that is a member of the Janthinidae Family of Purple Sea Snails. They are also known as the Common Purple Sea Snail, Common Janthina, and Large Violet Shell and in Mexico as lantana morada. The shells have a globular shape with six whorls, a fairly low spire (when compared to other Purple Sea Snails in the region) and a smooth exterior surface. The top exterior surface of the shell is purple to violet in color and the bottom is lavender to white. Violet Sea Shells reach a maximum diameter of 4.0 cm (1.6 inches).

Violet Sea Snails are found floating on the surface of the open sea in the warmer portions of the Pacific and Atlantic Oceans. They have been recorded in the central and southern Sea of Cortez, from, Santa Rosalia to the Cabo San Lucas, Baja California Sur.

There are more than thirty synonyms for this species, probably due, in part, to its widespread range.