Scotch Bonnet (also known as the Banded Bonnet)
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Cassidae, Genus: Semicassis, Species: Semicassis granulata · Cassidae (Helmet and Bonnet family) · Gastropod (spiral, whole shell)
Species
Semicassis granulata
Shell Type
Gastropod (spiral, whole shell)
Family
Cassidae (Helmet and Bonnet family)
Size
Approximately 1.5 inches, which is on the smaller side for this species. Adults typically range from 2 to 4 inches.
Color & Pattern
Cream to off-white base color with distinct yellowish-orange rectangular or square markings forming horizontal bands across the rounded body whorl.
Rarity
Uncommon to Rare as a whole, undamaged beach find, though weathered specimens are occasionally found after storms.
Habitat
Shallow subtidal waters, sandy bottoms, and offshore sand bars, typically ranging from low tide mark down to about 150 feet.
Geographic Range
Western Atlantic Ocean, from North Carolina through the Gulf of Mexico, Caribbean Sea, and down to Brazil.
Description
A charming, globose shell featuring a low spire, distinct cancellate (grid-like) sculpting formed by intersecting axial ribs and spiral cords, and a flaring outer lip that is slightly toothed.
Key Features
Rounded, inflated body whorl, granular grid-like surface texture, distinct yellowish-brown or orange banding, and a thickened outer lip.
Collector Value
Moderately desirable among shell collectors due to its attractive pattern and pleasing shape. Values range from a few dollars for beach-worn specimens to $15-$30 for gem-quality live-collected shells.
Condition Notes
The specimen appears to be in good to fine condition with clear pattern retention, though showing signs of minor beach wear on the spire.
Interesting Facts
Live Scotch Bonnet snails feed almost exclusively on sea urchins, using their acidic secretions and radula to drill into or pry open their prey.
Ecological Role
Acts as a specialized carnivore controlling sea urchin populations in benthic marine environments, helping to maintain balance in nearby coral reef and seagrass ecosystems.
Similar Species
Can be confused with the Mediterranean Bonnet (Semicassis saburon) or other Cassidae species, which differ in regional distribution and exact nodule or rib patterns.
Beach Finding Tips
Best found by beachcombing along sandy shores in the southeastern United States and the Gulf of Mexico following heavy storms or offshore winds.