Common Jingle Shell, Mermaid's Toenail, Baby's Footprint
Phylum: Mollusca, Class: Bivalvia, Order: Pectinida, Family: Anomiidae, Genus: Anomia, Species: Anomia simplex · Anomiidae (Jingle shells) · Bivalve (upper valve); Shape is sub-circular or irregular/discoid.
Species
Anomia simplex (Confidence: 95%)
Shell Type
Bivalve (upper valve); Shape is sub-circular or irregular/discoid.
Family
Anomiidae (Jingle shells)
Size
Approximately 1-1.5 inches in diameter. This is a standard adult size; the species typically ranges from 0.5 to 3 inches.
Color & Pattern
Translucent silvery-grey to translucent tan with a subtle pearly iridescence. This specific specimen appears somewhat weathered or 'fossilized' in color, lacking the bright yellow or orange hues often seen in fresh beach finds. No distinct pattern, but visible concentric growth lines.
Rarity
Very Common. These are some of the most frequently found shells on North Carolina beaches, though finding thin, translucent specimens in perfect condition is rarer.
Habitat
Marine, intertidal to shallow subtidal. Found attached to hard substrates like rocks, oyster reefs, pilings, or other shells.
Geographic Range
Western Atlantic, ranging from Nova Scotia, Canada, to Brazil, including the Gulf of Mexico and Caribbean.
Description
A thin, translucent, and delicate bivalve shell. This is the upper (left) valve, which is convex and lacks the hole found in the lower valve. The texture is smooth but slightly scaly due to concentric growth layers. It has a characteristic 'waxy' appearance and a metallic or pearly luster that catches the light.
Key Features
Translucency, pearly luster, and irregular edges. Unlike most bivalves, it lacks a prominent hinge tooth. The most diagnostic trait of the family is the hole in the bottom valve (not present here as this is an upper valve).
Collector Value
Low monetary value ($0.25 - $1.00) due to abundance, but highly desired for crafts and jewelry-making. Collectors value specimens with high translucency or deep gold/orange hues.
Condition Notes
Fair to Good. The shell is intact but shows significant 'weathering' or thickening typical of older shells washed up in the surf. It lacks the high translucency of fresh specimens but retains a nice iridescent sheen. Grade: Fine (Commercial/Beach Grade).
Interesting Facts
They are called 'Jingle shells' because they make a glassy tinkling sound when several are shaken together in a bag or strung as a wind chime. The living animal attaches to surfaces using a calcified byssus (thread) that passes through a permanent hole in its lower valve.
Ecological Role
Filter feeders that help clear the water of plankton and organic detritus. They serve as a food source for boring gastropods (like oyster drills) and sea stars. They are not currently a species of conservation concern.
Similar Species
Pododesmus rudis (Atlantic False Jingle), which is typically thicker, more opaque, and has a more ribbed exterior.
Beach Finding Tips
Look along the wrack line (high tide line) after a storm. They are very light and often get pushed to the very top of the beach. Holden Beach is an excellent spot for them, especially near the West End.
Notes
Holden beach nc