Coffee Bean Shell / Coffeebean Trivia
Phylum: Mollusca | Class: Gastropoda | Order: Littorinimorpha | Family: Triviidae | Genus: Trivia | Species: Trivia pediculus · Triviidae (Coffee Bean Shell family / Little Egg Cowries) · Gastropod (snail/univalve), whole shell, ovate to globose shape
Species
Trivia pediculus
Shell Type
Gastropod (snail/univalve), whole shell, ovate to globose shape
Family
Triviidae (Coffee Bean Shell family / Little Egg Cowries)
Size
Approximately 0.4 inches (10 mm), which is typical for an adult specimen of this species. Adults generally range from 8 to 15 mm.
Color & Pattern
Warm reddish-brown to pinkish-tan base color, featuring distinctive darker brownish spots or blotches across the dorsum, separated by prominent transverse ribs. The underside is paler, featuring a narrow aperture lined with distinct teeth along both lips.
Rarity
Common, frequently found by dedicated beachcombers and snorkelers in the Caribbean and southern Florida.
Habitat
Found in shallow subtidal waters and intertidal zones, typically inhabiting coral reefs, rocky areas, and under stones or gorgonians where they feed on tunicates.
Geographic Range
Western Atlantic Ocean, including the Caribbean Sea, the Gulf of Mexico, Florida, and south through the West Indies to Brazil.
Description
A charming, miniature marine gastropod that strongly resembles a roasted coffee bean due to its plump, oval shape and deep central dorsal furrow. The shell is sculpted with numerous sharp, continuous transverse ribs that run uninterrupted from the outer lip across the back to the inner margin. The aperture is long, narrow, and flanked by fine, distinct denticles on both sides, giving it a neat, highly tactile appearance.
Key Features
Ovate, bean-like shape, a distinct longitudinal groove (sulcus) running down the center of the back, and continuous transverse ribs that cross the entire dorsum.
Collector Value
Inexpensive and widely accessible, making them popular staples for miniature shell collections, shell crafts, and educational displays. Typically sold for a nominal price.
Condition Notes
The visible specimen appears to be an intact, whole shell with a warm natural coloration and well-preserved ribs, falling into the Good to Fine collectibility grade.
Interesting Facts
Despite their superficial resemblance to cowries (Cypraeidae) due to their smooth, glossy appearance and toothed aperture, Coffee Bean shells are actually more closely related to false limpets and wentletraps. They feed exclusively on colonial tunicates (sea squirts) using a specialized radula.
Ecological Role
Functions as a specialized micro-predator controlling tunicate populations on coral reefs. They serve as a food source for small carnivorous fish and invertebrates.
Similar Species
Atlantic Coffee Bean (Niveria quadripunctata), which is generally smaller with four distinct dark spots on the back, and the Gray Trivia (Trivia nix), which lacks the prominent reddish spots.
Beach Finding Tips
Best found by sifting through shell drift along high-tide lines in the Caribbean or by examining coral rubble and shell grit in shallow reef areas at low tide.