The snail's shell is reverse countershaded, because of its upside-down position in the water column. In addition to the bubble raft, only the veliger, or larval stage, has an operculum, and the shell is paper-thin to allow the animal to float upside down at the surface.įive views of a shell of Janthina janthina janthina is a member of the family Janthinidae, snails that trap air bubbles with a layer of clear chitin to maintain their positions at the surface of the ocean where they are predators on hydrozoans. These snails are pelagic, drifting on the surface of the ocean, where they feed upon pelagic hydrozoans, especially the by-the-wind sailor Velella velella and the Portuguese man o' war Physalia physalis.
#Violet storm snails free#
They have veliger or free swimming larvae, but the adults do not swim and cannot create their rafts except at the surface where air bubbles are available. These snails are a unique part of the pleuston, organisms living on or at the very surface of the water, because of their relatively large size. They are often found in large groups and sometimes become stranded on beaches when they are blown ashore by strong winds. This information was obtained through an academic study of the differences between the different species within this genus. More specifically, this species is located in the tropical and subtropical Atlantic, Indian and Pacific oceans. This species is found worldwide in the warm waters of tropical and temperate seas, floating at the surface. Image of Janthina Janthina, also known as the Violet Sea-Snail, in Manchester Museum Janthina janthina, common name the violet sea-snail or common violet snail, is a species of holoplanktonic sea snail, a marine gastropod mollusk in the family Epitoniidae, the violet snails or purple storm snails. Janthina planispirata Adams & Reeve, 1848 Janthina fragilis Lamarck, 1799 (junior synonym) Janthina britannica Forbes & Hanley, 1853 This is the normal view from above: the spire of the shell is held pointing down like this when the animal is floating on the surface of the ocean water. The violet color is apparant on the underside:Ī live Janthina janthina (with bubble raft) that has been swept up onto a beach in Maui, Hawaii. Beachcomber's Guide to Gulf Coast Marine Life: Texas, Louisiana, Mississippi, Alabama and Florida. "Complex fluids in animal survival strategies". Bergfreund, Jotam Bertsch, Pascal Gstöhl, Stefan J. "Females floated first in bubble-rafting snails". B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1. Pelagic Snails: The Biology of Holoplanktonic Gastropod Mollusks. "Molecular and Morphological Systematics of Neustonic Nudibranchs (Mollusca: Gastropoda: Glaucidae: Glaucus), with Descriptions of Three New Cryptic Species". ^ Churchill, Celia Valdes, Angel Foighil, Diarmaid (2014).Wonders of Western Waters: The Marine Life of South-Western Australia. ^ a b c d e Morrison, Sue Storrie, Ann (1999).World Register of Marine Species (WoRMS). ^ "Janthina janthina (Linnaeus, 1758)".Accessed through: World Register of Marine Species at on Its common names include violet sea-snail, common violet snail, large violet snail and purple storm snail. Janthina janthina is a species of holoplanktonic sea snail, a marine gastropod mollusk in the family Epitoniidae. Janthina planispirata Adams & Reeve, 1848.
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