Florida Horse Conch (also known as the Giant Horse Conch)
Phylum: Mollusca, Class: Gastropoda, Order: Neogastropoda, Family: Fasciolariidae, Genus: Triplofusus, Species: T. giganteus · Fasciolariidae (Tulip and Horse Conch family) · Gastropod (univalve); Spiral-fusiform shape with a long siphonal canal.
Species
Triplofusus giganteus (formerly Pleuroploca gigantea)
Shell Type
Gastropod (univalve); Spiral-fusiform shape with a long siphonal canal.
Family
Fasciolariidae (Tulip and Horse Conch family)
Size
Estimated at 8–10 inches based on the image perspective; it is a sub-adult. This species can grow up to 24 inches, making it one of the largest gastropods in the world.
Color & Pattern
Exterior is a pale apricot to dirty white (sun-bleached coral/tan). The interior aperture displays a vibrant, characteristic deep salmon-orange. The thick brown periostracum (outer skin) is absent on this specimen, likely worn away by surf and sun.
Rarity
Common (found regularly on beaches, though large, intact specimens with original color and periostracum are harder to find).
Habitat
Found in shallow marine waters, particularly on sand or mud flats and around seagrass beds. It ranges from the intertidal zone to depths of 20 fathoms (120 feet).
Geographic Range
Western Atlantic: from North Carolina, USA, south to the Gulf of Mexico and the Caribbean to Brazil.
Description
A massive, robust shell with a heavy, spindle-shaped structure. It features about 10 whorls with prominent, rounded knobs on the shoulder. The aperture is large and oval, terminating in a long, relatively straight siphonal canal. The surface is sculpted with numerous fine spiral cords.
Key Features
Huge size potential, bright orange aperture, long siphonal canal, and large nodules (bumps) on the shoulders of the whorls.
Collector Value
Varies by size. Beach-worn specimens like this are worth $10–$30. Gem-quality specimens exceeding 18 inches with a dark brown periostracum can fetch $100–$300+ due to their impressiveness in a display.
Condition Notes
Fair condition for a beach find. The apical tip (spire) appears slightly worn, and the outer lip shows some chipping. The specimen is sun-bleached on the exterior, but the interior still retains its desirable orange hue. Collectibility Grade: Good.
Interesting Facts
It is the State Shell of Florida. Despite its name, it is not a true conch (Strombidae) but a member of the Tulip shell family. It is a carnivorous predator that eats other large mollusks, including the Lightning Whelk and King’s Crown.
Ecological Role
Apex predator of the sandy bottom community. It controls the populations of other large gastropods. It is currently a species of concern in some areas due to over-harvesting and slow growth rates.
Similar Species
True Tulips (Fasciolaria tulipa) are smoother with distinct dark spiral lines. Banded Tulips (Cinctura hunteria) are much smaller with widely spaced dark lines.
Beach Finding Tips
Look in the wrack line after a strong storm or low tide on Gulf Coast beaches. Their large size makes them easy to spot, but they are often partially buried in sand or snagged in seagrass clumps.