Chthamalus fragilis

Chthamalus fragilis is a small gray barnacle found in the upper intertidal zone of the northwestern Atlantic Ocean, from approximately Cape Cod southward to Florida and into the Caribbean and Gulf of Mexico. The species is believed to have been distributed only as far northward as South Carolina or Virginia as recently as the late 1800s, when it was noticed along the Massachusetts coast. The species may have expanded its range naturally or been introduced to New England through anthropogenic activities.