Delaware Shells

Razor clams, shark eyes, knobby conchs … do you know your Delaware shells? Take a look at some local examples from the Museum’s collection of more than two million shells. Use this guide to identify shells for your own collection! Many hobbyists enjoy picking up nature’s curios on the beach for home displays or creative shell art. Serious collectors note the date and location where each shell was found, instantly making the shell scientifically valuable to researchers. Grab a bucket, hit the beach, and happy hunting!

Source: MAS Bulletin/University of Delaware Sea Grant College Program, A Guide to Field Identification: Seashells of North America by R. Tucker Abbott, DMNH collection.

Channeled Whelk
Busycotypus canalicutatus
Similar to the knobby conch, but with grooves instead of knobs along the whorl. Egg cases are found in 12–30 inch chains along the beach in spring.

Knobbed Whelk
Busycon carica
One of the largest shells found on Delaware beaches. White, violet, and brown shells grow up to nine inches long. Eats other mollusks on the bottom of the ocean by wrapping its foot around bivalves and using its own shell to pry open prey and insert its mouth parts.

Oyster
Crassostrea virginica
Rough, white shells have a large purplish spot on the inside that marks where the muscle that held the two valves together was. Their shape depends on what they were attached to and how crowded the environment was. Females can produce up to 100 million eggs at one spawning.

Bay Scallop
Argopecten irradians
Popular fan-shaped shells in a palette of colors like white, orange, pink, and brown. They swim by opening and closing shells and have many eyes that sense light to detect the shadows of predators.

Blood Ark
Anadara ovalis
Small teeth stick out from a ridge on the inside near the hinge of this bivalve. Grows to lengths of one to three inches.

Blue Mussel
Mytilus edulis
Triangular shape with fine circles on surface. Holds onto objects with strong threads called “byssal fibers.” Moves by releasing threads, drifting, and then making new fibers

Common Slipper Shell
Crepidula fornicata
Aptly named shells look like tiny slippers. White with brown or purple spots. Live attached to hard objects including other shells, and clump together.

Jingle Shell
Anomia simplex
Popular in jewelry. Translucent shells come in white, orange, yellow – and sometimes black when buried in dirt for a long time.

Common Periwinkle
Littorina littorea
Dark brown surface with fine grooves. May have crossed the Atlantic from Europe attached on the bottoms of ships.

False Angel Wing
Petricolaria pholadiformis
Similar to angel wings but smaller. Tell apart by ridges that fade at one end on false angel wing.

Ribbed Mussel
Geukensia demissa
Shaped like a footprint, this brownish or bluish green shell has rough texture and is found in marshy areas. Often attached to the base of marsh grass.

Shark Eye
Neverita duplicata
Lives in sand and has spherical shape with white, grey, or brown.

Soft Shell Clam
Mya arenaria
Imperfect oval-shaped, cannot completely close its shell. Burrows deep to escape most predators.

Angel Wing
Cyrtopleura costata
Dainty, wing-shaped shells with bumps on outer surface that make up ridges. Usually white, somewhat rare in Delaware. Live about a foot deep in mud.

False Angel Wing
Petricolaria pholadiformis
Similar to angel wings but smaller. Tell apart by ridges that fade at one end on false angel wing.

Atlantic Jackknife Clam
Ensis directus
Shaped like straight razor, up to six inches long. Live vertically in mud and can burrow quickly.

Oyster Drill
Urosalpinx cinerea
Emits a chemical that softens oyster shells, then scrapes a hole through with a ribbon of teeth to eat the oyster’s soft body.

Atlantic Surf Clam
Spisula solidissima
Two to five inches long. Teeth help shell align properly when it closes.