Cyrtopleura costata
| Cyrtopleura costata | |
|---|---|
 |
|
| Cyrtopleura costata | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Myoida |
| Family: | Pholadidae |
| Genus: | Cyrtopleura |
| Species: | C. costata |
| Binomial name | |
|
Cyrtopleura costata Linnaeus, 1758 |
|
| Synonyms | |
|
|
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, living in the seabed, where it burrows through sand and mud to a depth of up to 3 feet (0.91 m).
Cyrtopleura costata has a pair of brittle, asymmetric white valves and can grow to about 7 inches (180 mm) in length. The anterior end is elongated and has a rounded point which is used for digging through the substrate. The posterior end is truncated and rounded and near the beak has an apophysis, a wing-like flange, which helps provide an attachment for the foot muscles. On the anterior side of the beak, the margin is smooth and bent slightly upwards. The whole valve has finely sculptured radial ribs which intercept with a series of concentric growth rings parallel with the margin. In the living animal, the valves are covered by the periostracum, a thin grey protective layer. This coating has usually been abraded when the empty shells are washed up on the beach, and the valves are usually found singly because the muscles that hold them together are weak. Internally, the live mollusc has a powerful muscular foot and a pair of long, fused siphons. These siphons are unable to retract back into the shell and as a result, the two valves permanently gape apart.
Cyrtopleura costata is found in shallow seas in the north west Atlantic Ocean between Cape Cod and the Gulf of Mexico. It is also found in the West Indies, Central America and as far south as Brazil. It is commonest in the intertidal zone and just below low water mark.
Cyrtopleura costata lives beneath the surface of the sea bed. It is able to bore through sand, mud, wood, clay and even soft rock using a twisting motion of its pointed, anterior end assisted by jets of water ejected from the mantle cavity. It is a filter feeder. The siphons extend to the surface of the substrate and water is drawn in through one and expelled through the other with microalgae and zooplankton being filtered out as the water passes through the gills. Respiration takes place at the same time. Cilia then waft the food particles to the mouth.
...
Wikipedia