Mollusca · mollusks
Eastern oyster
Crassostrea virginica
Ostreidae · true oystersIUCN: Not evaluated
A reef-building oyster of Atlantic estuaries from Canada to the Gulf.
Fun factOne adult can filter up to 190 liters of water a day.
- Waters
- Northeast US, Northwest Atlantic, Tropical Atlantic & Caribbean
- Depth zone
- Coastal shallows & estuaries, Intertidal shore
- Diet
- Plankton (filter feeder)
- Size
- Shell up to 20 cm
Classification
Mollusca › Bivalvia › Ostreidae
- Kingdom Animalia animals
- Many-celled organisms that eat other living things for energy (heterotrophs)
- Cells have no cell walls
- Most can move at some stage of life
- Clade Bilateria bilateral animals
- Body has a left and right side that mirror each other (bilateral symmetry)
- Head end with concentrated nerves; three tissue layers
- Includes about 99% of all living animal species
- Clade Protostomia protostomes
- In the embryo, the first opening usually becomes the mouth
- Main nerve cord runs along the belly (ventral)
- Includes mollusks, worms, and arthropods
- Clade Spiralia mollusks, worms & kin
- Embryos usually divide in a spiral pattern (spiral cleavage)
- Many have a swimming larva with a band of cilia (trochophore)
- Includes mollusks and segmented worms
- Phylum Mollusca mollusks
- Soft body with a muscular foot and a fold of tissue (mantle) that makes the shell
- Most have a rasping, tongue-like ribbon of teeth (radula)
- Includes snails, clams, octopuses, and chitons
- Class Bivalvia clams, oysters & kin
- Body enclosed in two hinged shells (valves)
- No head and no radula
- Most filter food from water with large gills
- Subclass Pteriomorphia oysters, scallops & mussels
- Often attach to surfaces with threads (byssus) or cement
- Includes oysters, scallops, mussels, and pearl oysters
- Family Ostreidae true oysters
- Oysters: one shell cemented to a hard surface
- Build reefs that filter water and shelter other animals
- Genus Crassostrea
- Species in the same genus are very close relatives and often look alike.
- Species Crassostrea virginica Eastern oyster
Closest relatives in the guide
- Atlantic jackknife clam Ensis leei same class
- Atlantic sea scallop Placopecten magellanicus same class
- Atlantic surfclam Spisula solidissima same class
- Bay scallop Argopecten irradians same class
- Blue mussel Mytilus edulis same class
- Giant clam Tridacna gigas same class
- Hard clam Mercenaria mercenaria same class
- Ocean quahog Arctica islandica same class