Bivalvia (/ b aɪ ˈ v æ l v i ə /) or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed by a calcified exoskeleton consisting of a hinged pair of half-shells known as valves.

Jan 5, 2023 · Bivalves (also called pelecypods) are clam and clam-like, shelled invertebrate (lacking a backbone) animals. Bivalves are a class of mollusk with two valves, which is where they get their name (“bi” means two in Latin). They are the second-most common seashells in the world today behind their cousins, the gastropods (snails).

bivalve, (class Bivalvia), any of more than 15,000 species of clams, oysters, mussels, scallops, and other members of the phylum Mollusca characterized by a shell that is divided from front to back into left and right valves. The valves are connected to one another at a hinge.

It is the second largest class of molluscs after the gastropods (snails & slugs). Unfortunately, most are cryptic, buried in sand or nestled in rocky crevices. The few listed here are ones most often encountered in the field by divers, but are only a tiny fraction …

The pelecypods are a type of mollusk that has two shells, hence the common name of bivalves. The shells are hinged together by a ligament that continually forces the shells open. Only special muscles, called adductor muscles, can close the shells together. Upon death, the shell springs open since the adductor muscle fails to work.

bivalve, Any member of the mollusk class Bivalvia, or Pelecypoda, characterized by having a two-halved (valved) shell. Clams , cockles, mussels, oysters , scallops, and shipworms are bivalves. Most are completely enclosed by the shell, the two valves of which are joined by an elastic ligament, and by two sheets of tissue called the mantle.

Nov 25, 2016 · Pelecypods evolved from the Early Cambrian (Tommotian) molluscan class Rostroconchia (Pojeta et al. in Science 177 (4045): 264–267, 1972; though this hypothesis is debatable). Rostroconchia are a group of Palaeozoic bivalved molluscs that now belong to a distinct class of their own (Pojeta and Runnegar 1976).

Learn about clams and bivalves (Pelecypoda spp.) benthic macroinvertebrates by exploring the life cycle, feeding habitats, interesting facts and their role in the food chain. Watch videos of the live benthics to see how they move and view pictures of their different life stages.

The Pelecypoda, Bivalva or Lamellibranchia (Latin for leaf-gill) (the only class with three names!!) is comprised of molluscs known more commonly as just u001cbivalves u001d, because they have two separate halves to their shells. They all have two-part shells, hinged dorsally.

A. CLASS BIVALVIA [or PELECYPODA] (clams, oysters, scallops, mussels, rudists) Name: Bivalvia means "two" (bi) + "shells" (valvia). Chief characteristics: Skeleton consists of two calcareous valves connected by a hinge.