denise
05-02-2009, 06:30 PM
Sea snails are characterized by a single, spiral shell into which they can withdraw when threatened or frightened. The operculum is a hard plate that seals the opening after the snail draws its body inside. Sea snails are part of the Mollusk group, closely related to octopii (http://www.scubadiver.cc/forums/showthread.php?t=433), slugs, cuttlefish, nudibranches. There are more than 40,000 species worldwide.
Sea snails have two pairs of tentacles on their head, with light sensitive eyespots at the base of the longer set of tentacles. The smaller pair of tentacles is used to smell and touch objects. All sea snails have gills in front of their heart which they use to exchange oxygen and carbon dioxide in the water. Sea snails range in size from 0.02 inches to more than 30 inches long (the marine Australian Trumpet snail). Most sea snails move about slowly by creeping and dragging themselves along using a muscular “foot”.
Sea snails are extremely diverse in habitat choice. They occupy the widest range of ecological niches in the ocean, from the sea shore, to shallow reefs, to the deepest of ocean trenches. Land snails have done the same on land, they live in every conceivable habitat from lakes, streams, ponds, springs, salt lakes, high mountains, deserts and rainforests!
Most sea snails eat living algae and seaweed, but some are scavengers and some are even active carnivores! They feed using their radula, a rough tongue-like organ that has thousands of tiny denticles (teeth) on it. This is used to “rasp” their prey before swallowing it. In turn, sea snails are eaten by fish.
http://www.dayo.com/fishid/gastropodscott_2.jpg
Photo by Scott LaPointe
The flamingo tongue snail, Cyphoma gibbosum, is a small (< 1 inch) brightly colored species of sea snail. The flamingo tongue feed by browsing on the tissues of various soft corals and sea fans.
http://www.scubadiver.cc/fishid/gastropod_11.jpg
Photo by Robert Palmer
The shell of this species is actually plain white, with a yellow tinge on the sides. The orange and black dots seen above is actually a layer of living tissue connected to the snail's foot that the snail pushes out to cover its shell. This tissue (called a mantle) works like a fish's gills, exchanging oxygen and carbon dioxide with the water so the snail can breathe. The mantle flaps can be retracted, exposing the shell, when the sea snail is threatened.
Flamingo tongue snails are usually very common in Florida, the Bahamas and the Caribeen, but have become scarce in some areas due to over-collecting by snorkelers and scuba divers, who make the mistake of thinking that the color is in the shell of the animal.
http://www.scubadiver.cc/fishid/seashellrobert_11.jpg
Atlantic Triton's Trumpet, Charonia variegata, Boynton Beach
Photo by Robert Palmer
Atlantic triton's trumpets are active predators that feed on other mollusks and starfish.
http://www.divetraining.net/pictures/2011_may_29_tortugas/P1010127.jpg
Atlantic Deer Cowrie Cypraea cervus spotted on a night dive in the Dry Tortugas
Sea snails have two pairs of tentacles on their head, with light sensitive eyespots at the base of the longer set of tentacles. The smaller pair of tentacles is used to smell and touch objects. All sea snails have gills in front of their heart which they use to exchange oxygen and carbon dioxide in the water. Sea snails range in size from 0.02 inches to more than 30 inches long (the marine Australian Trumpet snail). Most sea snails move about slowly by creeping and dragging themselves along using a muscular “foot”.
Sea snails are extremely diverse in habitat choice. They occupy the widest range of ecological niches in the ocean, from the sea shore, to shallow reefs, to the deepest of ocean trenches. Land snails have done the same on land, they live in every conceivable habitat from lakes, streams, ponds, springs, salt lakes, high mountains, deserts and rainforests!
Most sea snails eat living algae and seaweed, but some are scavengers and some are even active carnivores! They feed using their radula, a rough tongue-like organ that has thousands of tiny denticles (teeth) on it. This is used to “rasp” their prey before swallowing it. In turn, sea snails are eaten by fish.
http://www.dayo.com/fishid/gastropodscott_2.jpg
Photo by Scott LaPointe
The flamingo tongue snail, Cyphoma gibbosum, is a small (< 1 inch) brightly colored species of sea snail. The flamingo tongue feed by browsing on the tissues of various soft corals and sea fans.
http://www.scubadiver.cc/fishid/gastropod_11.jpg
Photo by Robert Palmer
The shell of this species is actually plain white, with a yellow tinge on the sides. The orange and black dots seen above is actually a layer of living tissue connected to the snail's foot that the snail pushes out to cover its shell. This tissue (called a mantle) works like a fish's gills, exchanging oxygen and carbon dioxide with the water so the snail can breathe. The mantle flaps can be retracted, exposing the shell, when the sea snail is threatened.
Flamingo tongue snails are usually very common in Florida, the Bahamas and the Caribeen, but have become scarce in some areas due to over-collecting by snorkelers and scuba divers, who make the mistake of thinking that the color is in the shell of the animal.
http://www.scubadiver.cc/fishid/seashellrobert_11.jpg
Atlantic Triton's Trumpet, Charonia variegata, Boynton Beach
Photo by Robert Palmer
Atlantic triton's trumpets are active predators that feed on other mollusks and starfish.
http://www.divetraining.net/pictures/2011_may_29_tortugas/P1010127.jpg
Atlantic Deer Cowrie Cypraea cervus spotted on a night dive in the Dry Tortugas