common periwinkle hides inside its shell, have a broadly ovate thick and sharply pointed shell, and contain whorls. fine threads

housing protect seashells beige invertebrate colorful marine aquatic murex snails fresh nourishment spiral shore life littorea seashell crawl animal gastropod littorina seafood mollusk creature whorl sea snail ovate periwinkle common beachcombing close up pointed coast seaside mollusc seashore edible coastal ocean beach sand small brown shell closeup nature