Unionid Mollusks from the Upper Cape Fear River 
Basin, North Carolina, with a Comparison of the 
Faunas of the Neuse, Tar, and Cape Fear Drainages 
(Bivalvia: Unionacea) 
Rowland M. Shelley 
North Carolina State Museum of Natural Sciences, 
P.O. Box 27647, Raleigh, North Carolina 27611 
ABSTRACT . — The unionid molluscan fauna of the piedmont portion 
of the Cape Fear River System consists of 10 genera and 15 species. 
Six additional species in the Coastal Plain part of the basin are known 
from literature records, and the reported occurrence of Alasmidonta 
heterodon (Lea 1830) cannot be verified. Elliptio complanata (Light- 
foot 1786), Uniomerus tetralasmas (Say 1831), Anodonta cataracta 
Say 1817, and Villosa delumbis (Conrad 1834) are numerical domi- 
nants, while Fusconaia masoni (Conrad 1834), Carunculina pulla 
(Conrad 1838), Lampsilis cariosa (Say 1817), Anodonta imbecilis Say 
1829, and Lasmigona subviridis (Conrad 1835) are least abundant. 
Photographic plates and diagnostic comments are provided to facili- 
tate identifications of unionids in the Atlantic drainages of North 
Carolina. 
Thirty years have elapsed since Walter (1956) surveyed the mol- 
lusks, of the upper Neuse River basin and provided the first detailed 
study on these invertebrates in a North Carolina drainage. Nine years 
later Dawley (1965) published an uncritical listing of freshwater mol- 
lusks for the entire state, based in part on Walter’s paper, the author’s 
personal collection, and materials at the Academy of Natural Sciences, 
Philadelphia, and the Museum of Zoology at the University of Michi- 
gan. Clarke (1983) published a comprehensive report on the mollusks of 
the Tar River system as part of an assessment of the status of the 
endemic spiny mussel, Elliptio ( Canthyria ) steinstansana Johnson and 
Clarke 1983. This study also included less intensive sampling in parts of 
the Roanoke (Roanoke and Cashie rivers) and Neuse (Neuse, Little, and 
Trent rivers) watersheds. Porter (1985) conducted a detailed sampling of 
the mollusks of Lake Waccamaw and the Waccamaw River system. 
These four works are the major ones dealing exclusively with aquatic 
mollusks of North Carolina, and additional records are available in 
Johnson (1967, 1970, 1984), Johnson and Clarke (1983), Fuller (1972, 
1973, 1977), Burch (1975), Porter and Horn (1980, 1983, 1984), Horn 
and Porter (1981), Clarke (1981, 1983, 1985), and Shelley (1983). Earlier 
literature pertinent to the state is summarized by Walter (1956). 
From 1971 to 1978 I sampled unionids non-quantitatively in the 
Piedmont Plateau section of the Cape Fear River basin, mostly in lower 
Brimleyana No. 13:67-89, July 1987 
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