Scotch Bonnet
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Cassidae, Genus: Semicassis, Species: Semicassis granulata · Cassidae (Helmet and Bonnet family) · Gastropod, whole shell, spiral shape
Species
Semicassis granulata
Shell Type
Gastropod, whole shell, spiral shape
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
Creamy white base color decorated with distinctive brownish-orange or reddish-brown square or rectangular spots arranged in spiral bands. The colors appear generally natural with slight weathering.
Rarity
Common
Habitat
Shallow subtidal waters down to moderate depths, typically found on sandy bottoms, sand flats, and near seagrass beds in marine environments.
Geographic Range
Western Atlantic Ocean, ranging from North Carolina through the Gulf of Mexico, the Caribbean, and down to Brazil.
Description
An attractive, sturdy rounded shell featuring distinct spiral ridges and rows of beaded granules, with a short spire and a large body whorl characteristic of the bonnet family.
Key Features
Rounded body whorl, granular spiral cords, short spire, and a relatively thin outer lip compared to its close helmet shell relatives.
Collector Value
Moderately popular among beachcombers and regional shell collectors; typically valued as an affordable and attractive display piece worth a few dollars depending on exact size and condition.
Condition Notes
Good condition with minor wear on the apex and surface, retaining most of its original pattern; overall collectibility grade is Good.
Interesting Facts
Scotch Bonnet snails are active nocturnal predators that specialize in feeding on sea urchins and sand dollars, using their acidic secretions and radula to bore into prey.
Ecological Role
Acts as an important carnivorous predator controlling sea urchin and echinoderm populations in benthic marine communities.
Similar Species
Other bonnet species such as the Banded Bonnet (Semicassis cicatrosa), which can be distinguished by different banding patterns and geographic distributions.
Beach Finding Tips
Best found by beachcombing after heavy storms or rough wave action along sandy Atlantic and Gulf coastlines, particularly in the morning during low tide.