84 Paul W. Parmalee, Walter E. Klippel, Arthur E. Bogan 



valves comprised 8% of the total. Although Scruggs (1960) reported A. 

 ligamentina as still present in Chickamauga and Kentucky reservoirs, 

 Pardue (1981) failed to recover it during mussel surveys of Watts Bar, 

 Chickamauga, and Nickajack reservoirs. With the possible exception of 

 a few relic individuals, this species appears to have been extirpated from 

 all stretches of the middle and upper Tennessee River. 



At least four and possibly five species (or forms, depending upon 

 the taxonomic approach) of Pleurobema were represented in the mid- 

 dens, and combined their valves comprised nearly 16% of the total. Of 

 the Pleurobema complex, valves of P. cor datum and P. plenum (Lea 

 1840), both of which today are usually found inhabiting large rivers at 

 depths of 3 to 6 m, were the most numerous. Pleurobema pyramidatum 

 (Lea 1834), another medium-to-large river deep water species, ranked 

 third in abundance within this complex. Of interest is the fact that com- 

 bined, all species of Pleurobema comprised approximately 24% of the 

 shells recovered at the two Mississippian sites, 16% of those at the Late 

 Woodland sites, and 23% of those at the Middle Woodland site. At 

 Widows Creek, valves of Pleurobema amounted to about 13% of the 

 total (Warren 1975). Continued harvesting of these species by the Indian 

 over a long period of time attests to their former abundance and proba- 

 ble habitation of the more shallow shoal areas of the river. Pleurobema 

 cordatum appears to be the only species of this complex still inhabiting 

 the upper Tennessee River. 



Ortmann (1918, 1925) considered Pleurobema clava (Lamarck 

 1819) a species of the Ohio River drainage, replaced in the upper Ten- 

 nessee River system by the form or species Pleurobema oviforme (Con- 

 rad 1834). The relationship between these two is still not clear, but they 

 do not appear to intergrade; Warren (1975) recorded both from the 

 Widows Creek site. Although specimens from the Chickamauga Reser- 

 voir middens should theoretically tend more toward P. oviforme, and 

 admittedly some were questionable, shells of this complex more closely 

 approached in appearance those of P. clava than those of P. oviforme 

 from the Duck River and tributary streams of the Tennessee River in 

 the northeastern part of the state. In any case, P. clava appears to have 

 been a part of the upper Tennessee River mussel assemblage since at 

 least Middle Woodland times, but it evidently was uncommon (valves 

 amounted to < 1% of the total). Lexingtonia dolabelloides (Lea 1840), a 

 "Cumberlandian" species once locally common in the middle and upper 

 Tennessee River and its tributaries, has been extirpated throughout 

 most of its range. Although valves of this species amounted to < 1% of 

 the total, they occurred in all middens examined. 



Shells of four species of Quadrula occurred in the middens, but 

 combined they totaled only 388, less than 2% of all specimens collected. 

 Valves of Q. metanevra (Raf. 1820) were the most numerous, followed 



