Florida horse conch - Triplofusus giganteus

Florida horse conch - Triplofusus giganteus
is a species of extremely large predatory subtropical and tropical sea snail.
This species is the largest gastropod in the American waters, and one of the largest univalves in the world.

This species shell length can reach 24 inches (600 mm).
The outline of the shell is somewhat fusiform, with a long siphonal canal, and having up to 10 whorls. Its sculpture present several spiral cords and axial ribs, some of which can form knobs on the whorls shoulders.
The shell color is bright orange in very young individuals. The shell often becomes greyish white to salmon-orange when adult, with a light tan or dark brown periostracum.

Know more:
http://en.wikipedia.org/wiki/Triplofusus_giganteus
http://www.jaxshells.org/pleuropl.htm
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