Scotch Bonnet
Phylum: Mollusca, Class: Gastropoda, Order: Littorinimorpha, Family: Cassidae, Genus: Semicassis, Species: S. granulata · Cassidae (Helmet and Bonnet shells) · Gastropod (univalve); whole shell with a globose, spiral shape.
Species
Semicassis granulata (with 95% confidence based on typical morphology)
Shell Type
Gastropod (univalve); whole shell with a globose, spiral shape.
Family
Cassidae (Helmet and Bonnet shells)
Size
Approximately 1.5 to 2 inches in length. This is an average juvenile to sub-adult size for this species, which can reach up to 4 inches.
Color & Pattern
Pale cream to off-white base with a distinctive pattern of orange to light-brown squared spots arranged in axial rows along the spiral ridges. The outer lip features brown manchas or squares. The shell appears naturally slightly matte due to beach wear.
Rarity
Common to Uncommon. While widely distributed, finding a fully intact specimen on the beach is a treat for casual collectors.
Habitat
Found in marine environments, specifically shallow subtidal zones and deep water on sandy substrates. They occur from depths of a few feet to over 300 feet.
Geographic Range
Western Atlantic, ranging from North Carolina through the Gulf of Mexico and the Caribbean down to Brazil.
Description
A classic globose shell characterized by a short spire and a large body whorl. The surface is decorated with numerous flat, spiral grooves (cords) that give it a textured, 'bonnet-like' appearance. It features a thickened outer lip and a polished columellar shield.
Key Features
Distinguished by its distinct square-dotted pattern, the presence of spiral grooves (striae), a wide aperture, and the reflected outer lip which usually bears rhythmic teeth or brown spots.
Collector Value
Modest value ($2-$10) for beach-found specimens depending on size and lip integrity. Highly desirable for thematic collections (e.g., State Shells) or those focused on the Cassidae family.
Condition Notes
The specimen shows light beach wear with some blurring of the fine spiral ridges near the apex; the apex is slightly eroded. Overall condition is 'Fine' - it is a high-quality beach find but not a 'Gem' live-taken specimen.
Interesting Facts
The Scotch Bonnet is the official state shell of North Carolina (the first state to designate one). In life, these snails are predators that hunt sea urchins and sand dollars, using sulfuric acid to bore through their prey's skeletons.
Ecological Role
Active predator of echinoderms. They help regulate populations of sea biscuits and sand dollars. They are not currently considered endangered, but local collection laws should always be checked.
Similar Species
Semicassis cicatricosa (Mediterranean Bonnet) which has more fine reticulation, and Phalium glaucum, which is larger with different spine arrangements.
Beach Finding Tips
Best found after storms or during extreme low tides on Atlantic and Gulf beaches. Look for them in shell piles just above the surf line where they may be partially buried in sand.