marine mussel

Marine mussels are usually wedge-shaped or pear-shaped and range in size from about 5 to 15 centimetres (about 2 to 6 inches). They may be smooth or ribbed and often have a hairy covering. The shells of many species are dark blue or dark greenish…

…as the true mussels (family Mytilidae) of marine and estuarine shores and the family Dreissenidae of fresh and estuarine waters. Such a shell form and habit evolved first within sediments (endobyssate), where the byssus serves for anchorage and protection when formed into an enclosing nest. Other bivalves have used the…