Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two shells of equal size connected by two adductor muscles and have a powerful burrowing foot. They live in both freshwater and marine environments; in salt water they prefer to burrow down into the mud and the turbidity of the water required varies with species and location; the greatest diversity of these is in North America.
Bivalvia, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. The class includes the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. Shipworms bore into wood, clay, or stone and live inside these substances.
Donax is a genus of small, edible saltwater clams, marine bivalve molluscs. The genus is sometimes known as bean clams or wedge shells; however, Donax species have numerous different common names in different parts of the world. In the southeastern U.S. they are known as "coquina", a word that is also used for the hard limestone concretions of their shells and those of other marine organisms.
The razor shell, Ensis magnus, also called razor clam, razor fish or spoot (colloquially), is a bivalve of the family Pharidae. It is found on sandy beaches in Canada and northern Europe.
Lajonkairia lajonkairii is an edible species of saltwater clam in the family Veneridae, the Venus clams. Common names include Manila clam, Japanese littleneck clam, Japanese cockle, and Japanese carpet shell. In Japan, it is known as asari. In Korea, it is known as bajirak.
Leukoma staminea, commonly known as the Pacific littleneck clam, the littleneck clam, the rock cockle, the hardshell clam, the Tomales Bay cockle, the rock clam or the ribbed carpet shell, is a species of bivalve mollusc in the family Veneridae. This species of mollusc was exploited by early humans in North America; for example, the Chumash peoples of Central California harvested these clams in Morro Bay approximately 1,000 years ago, and the distinctive shells form middens near their settlements.
Donax variabilis, known by the common name coquina, is a species of small edible saltwater clam, a marine bivalve mollusc in the family Donacidae, the bean clams. It is a warm water species which occurs in shallow water on sandy beaches on the east coast of the United States.
The Mediterranean mussel is a species of bivalve, a marine mollusc in the family Mytilidae. It is an invasive species in many parts of the world, and also an object of aquaculture.
The truncate donax, abrupt wedge shell, wedge clam or coquina clam, is a bivalve species in the family Donacidae.
Donax hanleyanus, common name the wedge clam, is a marine bivalve mollusk species in the family Donacidae, the bean clams or wedge shells. It is widely distributed throughout the sandy beaches of the Atlantic coast of South America, from Brazil to Argentina.
Ensis ensis, or the sword razor, is a razor clam, a marine bivalve mollusc in the family Pharidae. It lives buried in the sand and is found off the coasts of northwest Europe.
Donax vittatus, or the banded wedge shell, is a species of bivalve mollusc in the order Cardiida. It is found on beaches in northwest Europe buried in the sand on the lower shore.
Saxidomus gigantea is a large, edible saltwater clam, a marine bivalve mollusk in the family Veneridae, the venus clams. It can be found along the western coast of North America, ranging from the Aleutian Islands to San Francisco Bay. Common names for this clam include butter clam, Washington clam, smooth Washington clam and money shell.
Nuttallia obscurata, the purple mahogany clam, dark mahogany clam, varnish clam or savory clam, is a species of saltwater clam, a marine bivalve mollusk in the family Psammobiidae. It was first described to science by Lovell Augustus Reeve, a British conchologist, in 1857.
Donax fossor is a species of small saltwater clam, a marine bivalve mollusc species in the family Donacidae. This species is native to the eastern coast of the US, as far north as New York State; in the past it was sometimes incorrectly considered to be a northern, less colorful form of Donax variabilis.
Codakia distinguenda, the elegant lucine, is a species of marine bivalve mollusc. It was first described to science in 1872 by George Washington Tryon Jr.
Rangia cuneata or Atlantic rangia, also known as wedge clam, gulf wedge clam, common rangia, and cocktail clam, is a mollusc native to the Gulf of Mexico. It is an oval clam with a body length of up to 5cm, living from the intertidal zone to depths of 124 meters. It is edible and is harvested for food in Mexico, and has been so since pre-Hispanic times.
Megapitaria squalida, the chocolate clam, is a species of bivalve mollusc in the family Veneridae. It was first described to science by George Brettingham Sowerby, a British conchologist, in 1835. The type specimen was collected by Hugh Cuming.
