what lives in barnacles

Barnacles are small crustaceans that live in the ocean and attach themselves to hard surfaces like rocks, sea walls, boats, debris, and other marine animals. Although they were once thought to be related to snails, it turns out that barnacles are actually related to crabs and lobsters. They have a hard, white, cone-like shell that completely encases them. Barnacles are sessile, meaning they are non-mobile, and most are suspension feeders. They feed through feather-like appendages called cirri, which they use to comb the water for microscopic organisms. Barnacles have adapted their legs, called cirri, to sweep tiny food particles from the water column and pass them to their mouth parts inside their protective plates. Barnacles tend to live in shallow and tidal waters, typically in erosive settings, and are displaced by limpets and mussels, which compete for space. Some barnacles are internal parasites in other crustaceans, infiltrating and spreading within the body of their host and even altering its behavior and appearance.