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.
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.
Panopea is a genus of large marine bivalve molluscs or clams in the family Hiatellidae. There are 10 described species in Panopea. Many of them are known under the common name "geoduck".
Ostrea conchaphila is a species of oyster, a marine bivalve mollusk which lives on the Pacific coast of Mexico south of Baja California. Until recently there was some confusion as to whether this more southern oyster species might in fact be the same species as Ostrea lurida, the well-known but more northerly "Olympia oyster", which it resembles in shell size and color. Because of this confusion, the name O. conchaphila was sometimes applied to various populations of what is now known to be O. lurida.
Mulinia modesta is a species of clam belonging to the family Mactridae.
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.
Pitar is a genus of saltwater clams, marine bivalve molluscs in the subfamily Callocardiinae of the family Veneridae, the Venus clams. The genus contains over 60 species.
Arca zebra, or the turkey wing ark clam, is a bivalve mollusc in the family Arcidae, the ark clams.
Periglypta is a genus of bivalves in the subfamily Venerinae of the family Veneridae.
Hysteroconcha dione or the elegant Venus clam, formerly known as Venus dione, is a species of bivalve mollusc in the family Veneridae, the Venus clams.
Hysteroconcha lupanaria is a species of marine bivalve mollusc in the family Veneridae, the Venus clams.
Dosinia dunkeri is a species of saltwater clam, a marine bivalve mollusc in the family Veneridae.
Pinctada mazatlanica is a species of tropical marine bivalve mollusc in the family Pteriidae, the pearl oysters. It is known by the English common names pearl oyster, Mazatlan pearl oyster, and Panama pearl oyster. Spanish common names include madre perla, and ostra perlifera panameña. This mollusc was first described to science in 1856 by conchologist Sylvannus Charles Thorp Hanley. Pinctada mazatlanica produces gem-quality pearls and was the basis of a pearling industry in the Gulf of California for centuries.
Larkinia grandis is a genus of saltwater clams in the family Arcidae, the ark clams.
Modiolus capax, common name fat horsemussel, is a species of "horse mussel", a marine bivalve mollusc in the family Mytilidae, the mussels. It was first described to science by American malacologist Timothy Abbott Conrad in 1837. The type specimen was collected in San Diego by Thomas Nuttall.
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.
Saccostrea echinata, commonly known as the tropical black-lip rock oyster, blacklip rock oyster, blacklip oyster, and spiny rock oyster, is one of several tropical rock oyster species, occurring in tropical seas across the Indo-Pacific, including coastal waters across northern Australia to Noumea.
Anadara tuberculosa is a species of bivalves belonging to the family Arcidae.
Glycymeris longior is a species of living marine clam of the genus Glycymeris. It was common in the Quaternary on the Atlantic coast of South America. The shells of this species is frequently found on beaches from Patagonia to Brazil.
Hysteroconcha is a genus of saltwater clams, marine bivalve molluscs in the subfamily Callocardiinae of the family Veneridae, the Venus clams.
