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. Bivalves as a group have no head and they lack some usual molluscan organs like the radula and the odontophore. They include 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. The shipworms bore into wood, clay, or stone and live inside these substances.
A cockle is an edible, marine bivalve mollusc. Although many small edible bivalves are loosely called cockles, true cockles are species in the family Cardiidae.
Anadara trapezia, the Sydney cockle (NSW), or ark cockle (Queensland), is an estuarine filter-feeding bivalve. Its calcareous, heavily ribbed shell can grow to approximately 7 to 8 cm across. Its current range is along the east coast of Australia, from Queensland to Victoria. It has previously existed in Western Australia, South Australia, and the coast of New Zealand during the Middle Holocene. It has been used as a bioindicator/indicator species to study levels of the metals selenium, copper and cadmium.
The common cockle is a species of edible saltwater clam, a marine bivalve mollusc in the family Cardiidae, the cockles. It is found in waters off Europe, from Iceland in the north, south into waters off western Africa as far south as Senegal. The ribbed oval shells can reach 6 centimetres (2.4 in) across and are white, yellowish or brown in colour. The common cockle is harvested commercially and eaten in much of its range.
A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk. In life, the shell of this class of mollusks is composed of two hinged parts or valves. Bivalves are very common in essentially all aquatic locales, including saltwater, brackish water, and freshwater. The shells of bivalves commonly wash up on beaches and along the edges of lakes, rivers, and streams. Bivalves by definition possess two shells or valves, a "right valve" and a "left valve", that are joined by a ligament. The two valves usually articulate with one another using structures known as "teeth" which are situated along the hinge line. In many bivalve shells, the two valves are symmetrical along the hinge line—when truly symmetrical, such an animal is said to be equivalved; if the valves vary from each other in size or shape, inequivalved. If symmetrical front-to-back, the valves are said to be equilateral, and are otherwise considered inequilateral.
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.
Babelomurex cariniferus, common name Babel's latiaxis, is a species of sea snail, a marine gastropod mollusc in the family Muricidae, the murex snails or rock snails.
Americardia media, the Atlantic strawberry cockle, is a species of saltwater clam, a marine bivalve mollusc in the family Cardiidae, the cockles. This species can be found along the Atlantic coast of North America, from Cape Hatteras to the West Indies.
Acanthocardia is a genus of saltwater clams, marine bivalve molluscs in the family Cardiidae. Like most other bivalves, these mollusks are suspension feeders. This genus is present from the Upper Oligocene to the Recent.
Dinocardium is a genus of large saltwater clams or cockles, marine bivalve molluscs in the family Cardiidae, the cockles. There is only one species in the genus, Dinocardium robustum, or the Atlantic giant cockle.
Acanthocardia spinosa, the sand cockle, is a species of saltwater clams, marine bivalve molluscs in the family Cardiidae. The genus Acanthocardia is present from the Upper Oligocene to the Recent.
Acanthocardia aculeata, the spiny cockle, is a species of saltwater clams, marine bivalve molluscs in the family Cardiidae. The genus Acanthocardia is present from the Upper Oligocene to the Recent.
Barbatia barbata is a species of ark clam, a marine bivalve mollusk in the family Arcidae, the ark clams.
Dosinia exoleta, common name the rayed artemis, is a saltwater clam, a marine bivalve mollusc in the family Veneridae, the venus clams.
Panopea glycimeris is a species of large marine bivalve mollusc in the family Hiatellidae.
Laevicardium crassum, the Norwegian egg cockle, is a species of saltwater clam, a cockle, a marine bivalve mollusc in the family Cardiidae, the cockles.
Acanthocardia echinata, the prickly cockle or European prickly cockle, is a species of saltwater clam, marine bivalve molluscs in the family Cardiidae. The genus Acanthocardia is present from the Upper Oligocene to the Recent.
