Oyster mussel
Encyclopedia
The oyster mussel is a rare species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of freshwater mussel in the family Unionidae
Unionidae
Unionidae is a family of freshwater mussels, the largest in the order Unionoida, the bivalve mollusks sometimes known as river mussels, naiads, or simply as unionids.The range of distribution for this family is world-wide...

. This aquatic
Aquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...

 bivalve mollusk is native to Kentucky
Kentucky
The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth...

, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

, Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

, and Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...

 in the United States. It has been extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...

 from the states of Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...

 and North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...

. It is a federally listed endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

 of the United States.

This mussel was once widely distributed and common in the Cumberland
Cumberland River
The Cumberland River is a waterway in the Southern United States. It is long. It starts in Harlan County in far southeastern Kentucky between Pine and Cumberland mountains, flows through southern Kentucky, crosses into northern Tennessee, and then curves back up into western Kentucky before...

 and Tennessee River
Tennessee River
The Tennessee River is the largest tributary of the Ohio River. It is approximately 652 miles long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names...

 drainages, including many tributaries
Tributary
A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

. It has declined 80% from its historical abundance. It is now extirpated from the Cumberland River system and the main artery of the Tennessee River. It remains in the Nolichucky River
Nolichucky River
The Nolichucky River is a major stream draining the Blue Ridge Mountains of western North Carolina and east Tennessee. The river is long.-Hydrography:...

 of Tennessee and the Clinch River
Clinch River
The Clinch River rises in Southwest Virginia near Tazewell, Virginia and flows southwest through the Great Appalachian Valley, gathering various tributaries including the Powell River before joining the Tennessee River in East Tennessee.-Course:...

 in Tennessee and Virginia. Specimens remaining in the Duck River
Duck River (Tennessee)
The Duck River, long, is the longest river located entirely within the U.S. state of Tennessee. Free flowing for most of its length, the Duck River is home to over 50 species of freshwater mussels and 151 species of fish, making it one of the most biologically diverse rivers in North America.The...

 in Tennessee are likely members of a different species.

Like other freshwater mussels, this species reproduces by releasing its larvae, termed glochidia
Glochidium
The glochidium is a special microscopic larval stage of larger freshwater mussels, aquatic bivalve mollusks in the families Unionidae and Margaritiferidae, the river mussels and European freshwater pearl mussels....

, which lodge in the gills of fish to develop into juvenile mussels. Host fish species for this mussel include wounded darter
Etheostoma vulneratum
The common name of Etheostoma vulneratum is the wounded darter. It is one of the 324 fish species found in Tennessee....

 (Etheostoma vulneratum), redline darter
Etheostoma rufilineatum
The common name of Etheostoma rufilineatum is the redline darter. It is one of the 324 fish species found in Tennessee....

 (E. rufilineatum), bluebreast darter (Etheostoma camarum), dusky darter (Percina sciera), banded sculpin
Cottus carolinae
Introduction=Cottus carolinae, or the Banded Sculpin, is a freshwater fish dwelling mostly in small to moderate sized streams in areas of swift current. Young and juvenile C. carolinae fish can mainly be found in pools, riffles, and other shallow habitats while adult Cottus carolinae tend to prefer...

 (Cottus carolinae), black sculpin (Cottus baileyi), and mottled sculpin (Cottus bairdi).

The main threat to this species is habitat alteration such as channelization and impoundments
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

 of waterways, increased silt
Silt
Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...

, and pollution.

This mussel is propagated in captivity. Many juveniles have been released into appropriate habitat.
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