| Abra alba | |
|---|---|
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Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Cardiida |
| Superfamily: | Tellinoidea |
| Family: | Semelidae |
| Genus: | Abra |
| Species: | A. alba |
| Binomial name | |
| Abra alba (W.Wood, 1802) | |
| Synonyms | |
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Abra alba, or the white furrow shell, is a species of bivalve mollusc in the family Semelidae. It occurs in the northeastern Atlantic Ocean and the Mediterranean Sea, where it lives on the floor in shallow areas buried in soft sediments. [1]
Abra alba can grow to up to 2.5 cm (1 in) long but a more usual size is 1.5 centimetres. It has a pair of thin brittle valves that are translucent, semi-shiny and a dirty white colour with a pale brown periostracum. The shape is roughly oval and the posterior and anterior dorsal margins are almost straight and slope to rounded ends. Both margins are smooth and the anterior margin is a little longer than the posterior one. The valves have a sculpture of fine concentric lines and the growth stages of the animal are visible. The interior of the valves is somewhat glossy and the adductor muscle scars may be visible. The small brown ligament that holds the valves together is exterior. [2]
Abra alba is found on the coasts of northwest Europe and the Mediterranean Sea at depths down to 200 m (656 ft). It is common around the British Isles and in the North Sea. It prefers fine, silty sand, but is also found in mud or gravel. [2]
Abra alba feeds by means of a pair of separate long, extensible siphons, elongations of the mantle. It is mostly a deposit feeder but is also able to feed on suspended particles as does the tellin Tellina fabula , a species with which it is often associated. [1] The inhalant siphon gropes around widely over the surface of the substrate, actively drawing in detritus. [3] In studies of Liverpool Bay, a community that includes A. alba, Phaxas pellucidus (the transparent razor shell) and Lagis koreni (the trumpet worm) is likely associated with more than one habitat. [4]
A large number of very small eggs are produced from May to August. The larvae probably have a lengthy period as part of the zooplankton before settling out. Juveniles grow fast during the summer but the ones that settle in autumn seem to delay their further development until the following spring. The lifespan is usually one year but can extend to two. [1]
A siphon is an anatomical structure which is part of the body of aquatic molluscs in three classes: Gastropoda, Bivalvia and Cephalopoda.
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.
Mya truncata, common name the blunt gaper or truncate softshell, is a species of edible saltwater clam, a marine bivalve mollusk in the family Myidae.
Anodontia alba, or the buttercup lucine, is a species of bivalve mollusc in the family Lucinidae. It can be found along the Atlantic coast of North America, its range extending from North Carolina in the United States to the West Indies.
Ensis ensis, or the sword razor, is a razor clam, a marine bivalve mollusc in the family Pharidae. It lives buried in the sand and is found off the coasts of northwest Europe.
Fabulina fabula, the bean-like tellin, is a species of marine bivalve mollusc in the family Tellinidae. It is found off the coasts of northwest Europe, where it lives buried in sandy sediments.
Tellina tenuis, the thin tellin, is a species of marine bivalve mollusc in the family Tellinidae. It is found off the coasts of northwest Europe and in the Mediterranean Sea, where it lives buried in sandy sediments.
Tellimya ferruginosa is a species of small marine bivalve mollusc in the family Lasaeidae. It is found on the eastern side of the Atlantic Ocean.
Phaxas pellucidus, the transparent razor shell, is a species of marine bivalve mollusc in the family Pharidae. It is found buried in the seabed in coastal waters of northwest Europe, often in great numbers.
Lagis koreni, commonly known as the trumpet worm, is a species of marine polychaete worm found in European waters. It lives within a narrow conical tube made of grains of sand and shell fragments.
Venerupis decussata is a marine bivalve mollusc in the family Veneridae, commonly known as the cross-cut carpet shell.
Cyrtopleura costata, or the angel wing clam, is a bivalve mollusc in the family Pholadidae. It is found in shallow parts of the northwest Atlantic and also in the North Sea of Scotland coastline and west coast of the Adriatic Sea by a remote area in the Marche region in central Italy, living in the seabed, where it digs its burrows on a very slow revolving movement for years through soft sand and mud always to a max depth of 8ft but always below 3 feet (0.91 m) at the lowest tide.
Thracia convexa is a bivalve mollusc in the family Thraciidae.
Donax vittatus, or the banded wedge shell, is a species of bivalve mollusc in the order Cardiida. It is found on beaches in northwest Europe buried in the sand on the lower shore.
Poromya granulata, or the granular poromya, is a species of marine bivalve mollusc in the family Poromyidae. It is unusual among bivalves in being carnivorous. It is found in more northerly parts of the Atlantic Ocean.
Mulinia lateralis, the dwarf surf clam or coot clam, is a species of small saltwater clam, a bivalve mollusc in the family Mactridae. It occurs in the western Atlantic Ocean and the Caribbean Sea.
Venerupis corrugata, the pullet carpet shell, is a species of bivalve mollusc in the family Veneridae. It is found buried in the sediment on the sea bed in shallow parts of the eastern Atlantic Ocean. It is harvested for human consumption in Spain and other parts of Western Europe.
Theora mesopotamica is a species of saltwater and brackish water clam, a bivalve mollusk in the family Semelidae. This species is known from the northwestern end of the Persian Gulf, and from subfossil remains in brackish deposits in the lower Tigris–Euphrates basin of Iraq.
Solecurtus strigilatus, also known as the rosy razor clam, is a species of saltwater clam, a marine bivalve mollusc in the family Solecurtidae. This mollusc is a suspension feeder and can burrow with great rapidity to escape predators. It is an unusual bivalve in that its shell valves are too small to contain all the soft tissue, and the animal is unable to retreat into its shell.
Abra prismatica is a species of bivalve mollusc in the family Semelidae. It occurs in the northeastern Atlantic Ocean, the North Sea and the Mediterranean Sea, where it lives on the seabed, in shallow areas buried in soft sediment.
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