What are examples and characteristics of bivalves?

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. Bivalves have no head.

What are two characteristics of bivalves?

Three of the main characteristics of bivalves are:
  • Two equally sized shells that close together for protection using muscles.
  • A large, muscular foot that is used to bury within the lake or ocean bottom. …
  • A straw-like siphon which protrudes out of the shell to take in and get rid of water and food.

What is the main characteristic of bivalve molluscs?

Bivalve mollusks (e.g., clams, oysters, mussels, scallops) have an external covering that is a two-part hinged shell that contains a soft-bodied invertebrate.

What makes Bivalvia unique?

Bivalves have two shells, connected by a flexible ligament, which encase and shield the soft vulnerable parts of the creature. All 15,000 known species of bivalves are aquatic in nature, with close to 80% being marine (saltwater environments).

Why are they called bivalves?

The animal. Bivalves, which belong to the phylum Mollusca and the class Bivalvia, have two hard, usually bowl-shaped, shells (called valves) enclosing the soft body.

What is mean by Bivalvia?

noun. : any of a class (Bivalvia synonym Pelecypoda) of typically marine mollusks (such as clams, oysters, or scallops) that have a 2-valved hinged shell, are usually filter feeders, and lack a distinct head.

How are bivalves different from other mollusks?

As a group, bivalves 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.

What type of symmetry do bivalves have?

Bivalves typically display bilateral symmetry both in shell and anatomy, but there are significant departures from this theme in taxa such as scallops and oysters.

What are bivalves classified?

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.

What are 3 characteristics of Polyplacophora?

The main characteristics of Polyplacophora include (1) elongate or oval, dorsoventrally flattened, bilaterally symmetrical, marine; (2) with dorsal shell of eight plates embedded in a tough mantle; (3) mantle-edge stiffened (called the girdle); (4) large, muscular, ventral foot (girdle and foot can act as suction cup); …

How are bivalves different from other mollusks?

As a group, bivalves 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.

What are bivalves classified?

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.

What are some examples of bivalves?

Bivalvia/Lower classifications

What type of symmetry do bivalves have?

Bivalves typically display bilateral symmetry both in shell and anatomy, but there are significant departures from this theme in taxa such as scallops and oysters.

What is the main difference between bivalves and gastropods?

Comparing Bivalves and Gastropods

Bivalve shells are made of two pieces connected at a hinge. So, if you find a shell with a hinge, it must be a bivalve. Gastropods are one piece and usually have a spiral on the end.

Do bivalves have gills?

In most bivalves, the gills are involved with both respiration and ciliary suspension feeding (filtering small particles out of the water which are then transferred to the mouth by a pair of labial palps). Recent bivalves show a number of different gill morphologies depending largely on the feeding process employed.

How do you identify bivalves?

The bivalve shell is composed of two valves (“bi-valves”). The valves are joined by a hinge composed of tiny “teeth” and usually also an elastic ligament. The number, size and shape of the teeth as well as the position of the ligament are important characters for the identification of bivalves.

Do bivalves have eyes?

In bivalves, eye type varies between taxa, including photoreceptive cells in the mantle, pit eyes, mirror eyes, and compound eyes. Some bivalves possess multiple types of eyes along the mantle, such as ark clams (family Arcidae), which have both pit eyes and compound eyes (Nilsson, 1994; Patten, 1887; Waller, 1980).