Keyhole Limpet
Phylum: Mollusca, Class: Gastropoda, Order: Vetigastropoda, Family: Fissurellidae, Genus: Fissurella, Species: Fissurella barbadensis · Fissurellidae (Keyhole limpet family) · Gastropod, whole shell, oval cone shape with an apical perforation
Species
Fissurella barbadensis
Shell Type
Gastropod, whole shell, oval cone shape with an apical perforation
Family
Fissurellidae (Keyhole limpet family)
Size
Approximately 1 inch in length, which is average for this species. Adults typically range from 0.75 to 1.5 inches.
Color & Pattern
Whitish or cream base color with distinct radial bands of reddish-brown or purple. The colors appear somewhat sun-bleached and worn due to beach exposure, revealing the underlying calcium carbonate structure in areas.
Rarity
Common, frequently found by beachcombers exploring rocky shorelines and tide pools in its native range.
Habitat
Intertidal and shallow subtidal zones, typically found firmly attached to rocky substrates, boulders, and coral reefs where wave action is moderate to high. Marine environment.
Geographic Range
Western Atlantic, including the Caribbean Sea, the Gulf of Mexico, southern Florida, Bermuda, and down to South America.
Description
A charming and sturdy limpet shell characterized by its distinct oval base and conical profile. The exterior features a prominent grid-like texture formed by radiating ribs crossed by fine concentric growth lines. The defining feature is the small, oval keyhole-like opening near the apex, which serves an excretory and respiratory function for the living animal.
Key Features
Distinctive keyhole (apical perforation) at or near the top of the shell, strong radial ribs creating a scalloped margin, and alternating reddish-white color banding.
Collector Value
Low to moderate value. While very popular for educational collections and beginner shell enthusiasts due to their unique morphology, common worn specimens hold little monetary value and are rarely sold for significant prices.
Condition Notes
Fair condition. The shell shows moderate wear and sun-bleaching with some dulling of the original color patterns. Several small predatory boring holes are visible near the apex. The margin is relatively intact. Collectibility grade: Fair.
Interesting Facts
Unlike typical snails whose shells grow in a spiral, keyhole limpets grow as a simple cone. The keyhole at the top allows water to flow over the gills and expelled waste to exit cleanly away from the animal's head.
Ecological Role
Keyhole limpets are important marine herbivores that graze on microalgae growing on rocks, helping to maintain the balance of benthic algae communities in intertidal ecosystems.
Similar Species
Other keyhole limpets such as the Lated Keyhole Limpet (Fissurella listeri), which can be distinguished by finer ribs and differences in the shape and position of the apical hole.
Beach Finding Tips
Search rocky beaches, limestone formations, and tide pools at low tide. Look closely among seaweed-covered rocks or inspect shell drift lines on high-energy shores.