Atlantic Kitten's Paw
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Plicatulidae, Genus: Plicatula, Species: gibbosa · Plicatulidae (Kitten's Paw family) · Bivalve (clams/two-shelled). This specimen is a single valve, characterized by a fan-like, folded shape.
Species
Plicatula gibbosa
Shell Type
Bivalve (clams/two-shelled). This specimen is a single valve, characterized by a fan-like, folded shape.
Family
Plicatulidae (Kitten's Paw family)
Size
Approximately 0.75 to 1 inch. This is a standard size for the species, which typically matures between 0.5 and 1.5 inches.
Color & Pattern
Creamy white to pale tan base with reddish-brown to purplish streaks along the ridges. The color appears somewhat faded due to wave action, which is common for beach-found specimens in NC.
Rarity
Common. They are very frequently found on North Carolina beaches, particularly after storms or high tides.
Habitat
Found in shallow marine waters, typically attached to hard substrates like rocks, dead shells, or coral rubble. They are common in the neritic zone.
Geographic Range
Western Atlantic, extending from North Carolina down through the Gulf of Mexico to the West Indies and Brazil.
Description
A thick, sturdy bivalve valve resembling a small feline paw. It features roughly 5 to 7 prominent, heavy radial ribs that create a distinctively zigzag or undulating margin. The texture is coarse and stony.
Key Features
Distinguished by its heavy, triangular or fan-like shape, deep radial folds (ribs), and a 'cat's paw' appearance created by the interlocking zigzag edge of the valves.
Collector Value
Low monetary value but high sentimental value for beachcombers. It is a 'must-have' for a complete collection of Carolinian province shells due to its unique morphology.
Condition Notes
Fair to Good. The shell shows signs of sea-wear with smoothed edges and some loss of vibrant color. There are visible 'sponge holes' or boring marks from Cliona sponge, which is typical for beach-drift shells in this region.
Interesting Facts
Unlike most clams, Kitten's Paws choose a spot and cement one valve permanently to a hard surface, much like an oyster. They are essentially 'sedentary' for their entire adult lives.
Ecological Role
Filter feeders that improve water quality by straining plankton. They provide micro-habitats for smaller organisms that live among their heavy ribs and are prey for sea stars and predatory snails.
Similar Species
Can be confused with juvenile Lion's Paw Scallops (Nodipecten nodosus), but Kitten's Paws lack the distinct 'ears' or auricles at the hinge and have a much thicker, stonier shell wall.
Beach Finding Tips
Look in the shell hash lines at low tide on Holden Beach. Because they are heavy and dense, they often settle in the 'heavier' pockets of shell debris near the water's edge.
Notes
Holden Beach, NC