DistributionRead full entry
Range DescriptionHistorically, this species was widespread in the upper Tennessee River system (Tennessee, Elk, Duck, Holston, north and south fork Holston, Nolichucky, French Broad, Tellico, Clinch, Powell Rivers) (Simpson 1914, Ortmann 1918) in Tennessee, Alabama, and Virginia, and possibly in the Cumberland River system (Cumberland, Big South Fork Cumberland, Caney Fork) where its former occurrence remains uncertain because the closely related Quadrula tuberosa was also reported there (USFWS 1984). It is likely that Ortmann's 1918-1925 records for the Cumberland River system were probably Quadrula tuberosa, here recognised as a synonym of Quadrula intermedia (USFWS 1984). Since 1960, it has been found in large tributaries of the Tennessee River including the Duck, Clinch, Elk and Powell Rivers. Since 1970, it has been found only in the Clinch, Powell and Tellico Rivers (USFWS 1984). It was recently found alive in the Duck River in Tennessee (L. Levine pers. comm. 1997). It appears to be extirpated from Alabama, although reintroduction efforts are underway (Mirarchi et al. 2004).
The extent of occurrence (EOO) is estimated at around 2,000-5,000 km2, with an area of occupancy (AOO) of around 500-2,000 km2.