Stiff Pen Shell
Atrina rigida
Markings and exact colorations may vary.
A big, brittle, fan-shaped shell that stands point-down in the sand and shatters in the surf.
- Typical size
- 5–10 in
- How often it turns up
- Common as fragments, uncommon whole
- Collecting
- Restricted
- Handling
- Sharp edges
Florida allows no live shelling in many counties and parks. If the animal is still inside, photograph it and put it back where you found it.
How to tell it apart
- Large triangular fan shape
- Thin, brittle, often with short spines
- Iridescent nacre inside the pointed end
Where to find these in Florida
Beaches rated very good or excellent for shells. Each page shows today’s score, the best window and access details.
- Anclote Key Preserve State Park · Tarpon Springs
- Bean Point · Anna Maria
- Beer Can Island (Greer Island) · Longboat Key
- Boca Grande Public Beach · Boca Grande
- Bowman's Beach · Sanibel
- Captiva Beach · Captiva
- Cayo Costa State Park · Cayo Costa
- Delnor-Wiggins Pass State Park · Naples
- Don Pedro Island State Park · Cape Haze
- Dr. Julian G. Bruce St. George Island State Park · St. George Island
- Gasparilla Island State Park · Boca Grande
- Gulfside City Park (Algiers Beach) · Sanibel
Found one?
Photograph it and BeachNut ranks the likely matches with a confidence read, then logs it to your collection with the beach and date.
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More shells in the field guide
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