Size

Shell length: Shell width: 2.5-4cm (1-1.5")

Recognition Characters

Shell is irregularly shaped but usually oval to circular in shape. Left valve (lower valve) forms a deep cup while the right valve (upper valve) forms a lid. Exterior of outer part of shell is rough and ornamented with scaly radial ridges that bear long spines or projections.

Color

Color varies, most often white or red-purple. Interior is tinged with purple.

Habitat & Depth

Attach to rocks, wrecks, and other hard substrates. Found in shallow water to 30m deep.

Distribution at GRNMS

Common at GRNMS. Can be found on variety of substrates and animals.

Geographic Range

North Carolina south to Brazil. Gulf coast to Texas, West Indies, and Bermuda

Behavior & Notes

Synonyms

References

Ruppert and Fox 1988, Abbott 2001