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.
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.
Zooxanthellae is a colloquial term for single-celled dinoflagellates that are able to live in symbiosis with diverse marine invertebrates including demosponges, corals, jellyfish, and nudibranchs. Most known zooxanthellae are in the genus Symbiodinium, but some are known from the genus Amphidinium, and other taxa, as yet unidentified, may have similar endosymbiont affinities. The true Zooxanthella K.brandt is a mutualist of the radiolarian Collozoum inerme and systematically placed in Peridiniales. Another group of unicellular eukaryotes that partake in similar endosymbiotic relationships in both marine and freshwater habitats are green algae zoochlorellae.
The giant clams are the members of the clam genus Tridacna that are the largest living bivalve mollusks. There are several species of "giant clams" in the genus Tridacna, which are often misidentified for Tridacna gigas, the most commonly intended species referred to as "the giant clam".
Tridacna is a genus of large saltwater clams, marine bivalve molluscs in the subfamily Tridacninae, the giant clams. They have heavy shells, fluted with 4 to 6 folds. The mantle is brightly coloured. They inhabit shallow waters of coral reefs in warm seas of the Indo-Pacific region. These clams are popular in marine aquaria, and in some areas, such as the Philippines, members of the genus are farmed for the marine aquarium trade. They live in symbiosis with photosynthetic algae (zooxanthellae). Some species are eaten by humans.
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.
Tridacna squamosa, known commonly as the fluted giant clam and scaly clam, is a species of bivalve in the family Cardiidae.
Hippopus hippopus, also known as the Horse Hoof clam and Strawberry clam, is a species of giant clam in the Subfamily Tridacninae and the genus Hippopus. Hippopus is a delicacy in many Southeast Asian countries due to its high quality meat.
Tridacna crocea, the boring clam, crocus clam, crocea clam or saffron-coloured clam, is a species of bivalve in the family Cardiidae. It is native to the Indo-Pacific region. It is occasionally found in the aquarium trade where it is often simply referred to as crocea.
Tridacna derasa, the southern giant clam or smooth giant clam, is a species of extremely large marine clam in the family Cardiidae.
Tridacna rosewateri is a species of marine bivalve in the family Cardiidae.
Freshwater bivalves are one kind of freshwater mollusc, along with freshwater snails. They are bivalves that live in fresh water as opposed to salt water, which is the main habitat type for bivalves.
Tridacninae, common name the giant clams, is a taxonomic subfamily of very large saltwater clams, marine bivalve molluscs in the family Cardiidae, the cockles.
Corculum is a genus of small saltwater clams, marine bivalve molluscs in the family Cardiidae, the cockles. They maintain Symbiodinium dinoflagellates as symbionts.
Corculum cardissa, the heart cockle, is a species of marine bivalve mollusc in the family Cardiidae. It is found in the Indo-Pacific region. It has a symbiotic relationship with dinoflagellates (zooxanthellae), which live within its tissues.
Fragum erugatum is a small species of cockle, a marine bivalve mollusc in the family Cardiidae. It is found in the shallow seas off the coast of Western Australia. It is commonly known as the Hamelin cockle, cardiid cockle or heart cockle.
Tridacna noae, also known as Noah’s giant clam or the Teardrop giant clam, is a species of giant clam. Up until recently, T. noae was confused with the small giant clam Tridacna maxima, but is now known to be its own independent species. It has a broad distribution in the Indo-Pacific.
Tridacna squamosina is a species of the Tridacna genus, the giant clams. These animals are bivalve mollusks belonging to the family Cardiidae identified by Sturany 1899.
Vepricardium is a genus of large saltwater clams, marine bivalve molluscs in the subfamily Cardiinae of the family Cardiidae, the giant clams.
