| Ostrea equestris | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Ostreida |
| Family: | Ostreidae |
| Genus: | Ostrea |
| Species: | O. equestris |
| Binomial name | |
| Ostrea equestris Say, 1834 | |
Ostrea equestris, commonly known as the crested oyster or horse oyster, [1] is a species of bivalve mollusc in the family Ostreidae. It can be found along the Atlantic coast of North and South America, ranging from Virginia to Patagonia.
The crested oyster is a rather irregular triangular or oval shape and grows to a length of about 5 cm (2 in). The two valves are quite different; the left one is deeply concave, has a raised margin and is fixed to the substrate while the right one is flattish and fits inside the other. The valves are thick with variable surface sculpturing, the whitish colour being obscured by mud, algal growth and encrusting organisms. The inside of the valves is pearly grey or greenish, and the muscle scar is colourless, a fact that distinguishes this species from the much larger eastern oyster (Crassostrea virginica) which has a purple muscle scar. [1]
The species is found in shallow water on the Atlantic coast of North, Central and South America. Its range extends from Virginia in the United States southwards to San Matías Gulf in Patagonia. It grows on rocks, shells, jetties, oil platforms and other hard substrates in the subtidal zone. [2] [3] [4]
The crested oyster has been eaten by humans for at least 6,000 years; the empty shells have been found in shell middens dating to that period on the coast of the Santa Lucía River basin where there were lagoons beside the estuary. [3] Other mollusc remains found in these middens include the bivalves Mytilus edulis and Plicatula gibbosa , which grow on hard surfaces, and Erodona mactroides , Tagelus plebeius , Mactra sp., Anomalocardia flexuosa , and the gastropods Buccinanops deformis and Heleobia sp., all of which are found on soft sediment in the intertidal and shallow subtidal zones; this suggests that they were gathered locally from the estuarine environment. [3]
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. 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. 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. The shipworms bore into wood, clay, or stone and live inside these substances.
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.
Ostrea lurida, common name the Olympia oyster, after Olympia, Washington in the Puget Sound area, is a species of edible oyster, a marine bivalve mollusk in the family Ostreidae. This species occurs on the northern Pacific coast of North America. Over the years the role of this edible species of oyster has been partly displaced by the cultivation of non-native edible oyster species.
Modiolus modiolus, common name northern horsemussel, is a species of marine bivalve mollusk in the family Mytilidae.
Isognomon alatus, the flat tree oyster, is a species of bivalve mollusc in the family Isognomonidae. It can be found along the Atlantic coast of North America, ranging from southern Florida to Brazil and Bermuda.
Isognomon radiatus, the radial purse oyster or Lister's tree oyster, is a species of bivalve mollusc in the family Isognomonidae. It can be found along the Atlantic coast of North America, ranging from southern Florida to Brazil and Bermuda.
Pteria colymbus, the Atlantic winged oyster, is a species of bivalve mollusc in the family Pteriidae. It can be found along the Atlantic coast of North America, ranging from North Carolina to Bermuda and Brazil.
Spondylus americanus, the Atlantic thorny oyster, is a species of bivalve mollusc. It can be found along the Atlantic coast of North America, ranging from North Carolina to Brazil.
Ostrea permollis, the sponge oyster, is a species of bivalve mollusc in the family Ostreidae. It can be found along the Atlantic Coast of North America, ranging from North Carolina to the West Indies.
Anomia simplex, the common jingle shell, is a typical species of bivalve mollusc in the family of Anomiidae, sharing attributes to blue mussels, American oysters, and bay scallops. Species related to the family of Anomiidae are often noted for their extremely thin, often translucent, paper-like shells. Anomia simplex can be found in shallow waters, typically estuaries, mainly along the Atlantic Coast of North America; however, they can range from as far north as the coast of Nova Scotia, and as far south as the coast of Brazil.
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.
Anodontia philippiana, or the chalky buttercup, is a species of bivalve mollusc in the family Lucinidae. It can be found burrowing in soft substrate in shallow waters along the Atlantic coast of North America, its range extending from North Carolina in the United States to the West Indies and Bermuda.
Pododesmus patelliformis, the ribbed saddle-oyster, is a species of bivalve mollusc in the family Anomiidae. It is found in the north east Atlantic Ocean.
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.
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.
Crassadoma is a genus of rock scallops, marine bivalve molluscs in the family Pectinidae. It is monotypic, the only species being Crassadoma gigantea, the rock scallop, giant rock scallop or purple-hinge rock scallop. Although the small juveniles are free-swimming, they soon become sessile, and are cemented to the substrate. These scallops occur in the eastern Pacific Ocean.
Saccostrea cucullata, the hooded oyster or Natal rock oyster, is a species of rock oyster found mainly in the Indo-Pacific Ocean.
Lopha cristagalli, the cockscomb oyster, is a species of marine bivalve molluscs in the family Ostreidae.
Octopus tehuelchus, commonly known as the Patagonian octopus, is a species of octopus, a marine cephalopod mollusc of the order Octopoda. It is native to shallow waters in the subtropical southwestern Atlantic Ocean. It was first described in 1834 by the French naturalist Alcide d'Orbigny.