78 
Rowland M. Shelley 
Lampsilis cariosa (Say 1817) Fig. 9-10. 
Diagnosis : Valves subovoid in outline, sexually dimorphic, periostra- 
cum smooth and yellow; post-basal mantle margin with ribbon-like flap. 
Localities : 14, 15. 
Remarks : Lampsilis cariosa is widely distributed along the eastern sea- 
board from Nova Scotia to Georgia (Johnson 1970, Burch 1975), but 
only five North Carolina records are cited — one each in the Tar and 
Cape Fear rivers, and three in the Neuse River. In the Tar, Clarke 
(1983) found living individuals and empty valves at five and six stations, 
respectively, from Franklin County in the Piedmont Plateau to Edge- 
combe County in the Coastal Plain. The present study records L. cari- 
osa from both the Haw and Deep river sub-basins, and as in the Tar, L. 
cariosa occurs in both physiographic provinces in the Cape Fear drain- 
age. 
Tribe Anodontini 
Andonta cataract a Say 1817 [= A. hallenbeckii Lea and A. doliaris Lea 
(Dawley 1965); and A. ( Pyganodon ) cataracta cataracta Say 
(Johnson 1970, 1984)]— Fig. 11-14. 
Diagnosis’. Valves moderately thick and heavy, without lateral or pseu- 
docardinal teeth, umbos extending beyond hinge line. 
Localities : 1, 2, 3, 4, 5, 6, 11, 13, 14, 17, 19, 26, C, M. 
Remarks: Anondonta cataracta, the most common anondontine mussel 
in North Carolina, is a variable species sometimes reaching large size, 
especially in impoundments. Figures 11 through 14 show four forms 
encountered in the Cape Fear basin. The species occurs from the St. 
Lawrence to the Alabama-Coosa river systems (Johnson 1970, Burch 
1975). In North Carolina, Johnson (1970, 1984) reported specific locali- 
ties in the Roanoke, Neuse, Cape Fear, Waccamaw, Yadkin, and 
Catawba drainages. Although A. cataracta is not known from the Tar 
watershed and was not encountered by Clarke (1983), it should be 
expected there and in any North Carolina drainage in headwater 
streams, farm ponds, and small impoundments. Both Walter (1956) and 
Johnson (1970) cite only one collection from the Piedmont portion of 
the Neuse basin, but A. cataracta was common in the adjacent part of 
the Cape Fear. As explained by Shelley 1983, it was erroneously 
reported from the Rocky River as A. implicata Say by Fuller (1977). 
Anodonta imbecilis Say 1829 — Fig. 15-16. 
Diagnosis’. Valves relatively thin and fragile, without lateral or pseudo- 
cardinal teeth, umbos flat, not protruding above hinge line. 
Localities’. 26, N. 
Remarks: Anodonta imbecilis occurs sporadically from the St. Law- 
rence to the Rio Grande river systems (Burch 1975). Walter (1956) 
