Prehistoric and Pre-Impoundment Populations of Freshwater Mussels (Bivalvia: Unionidaue) in the South Fork Holston River, Tennessee.

The South Fork Holston River is one of three major tributaries of the Holston River, originating in Smyth County in southwestern Virginia and flowing southwesterly and then northwesterly to where it enters the Holston River at Kingsport, TN. Three dams constructed in the 1950s. Fort Patrick Henry. Boone and South Holston, impounded the entire stretch of river flowing through Tennessee. Identification of shell recovered from two prehistoric aboriginal sites. Eastman Rocksbelter (40SL34) and Site 40SL330. and from two collections of relic shells plus species recorded from four localities by Ortmann (1918). provide evidence for a diverse and abundant naiad fauna prior to impoundment. Thirty-five species of mussels historically inhabited stretches of the South Fork Holston River flowing through Tennessee; all have been extirpated. Populations of Aetinonaias pectorosa. Lampsillis fasciola, Fusconaia subrotunda, and Ptychobranchus subtentum appear to have been four of the most abundant naiads inhabiting the river. In addition to the Asian clam. Corbiculafluminea. the giant floater (Pyganodon grandis) and paper pondshell (Utterbuckia imbecillis) are invader species now common throughout the reservoirs. [ABSTRACT FROM AUTHOR]