Please Note: Red text is defined in the Glossary

Description
The shell is elliptical in shape. The posterior ridge is rounded. Umbos are swollen and extend above the hinge line. Both the posterior and anterior ends of the shell are rounded. In general, the surface of the periostracum is roughened on the outer half of the shell. The periostracum is brown with dark greenish black rays over most of the shell. The nacre is usually pinkish or salmon with some iridescent blue showing through the pink toward the posterior end of the shell. The lateral teeth are long—two on the left valve and one on the right valve. Two pseudocardinal teeth are found on the left and right valves.

Distribution (see map)
The eastern lampmussel has a discontinuous range from the Pee-Dee Drainage Basin north to the St. Lawrence Drainage Basin. In North Carolina, it has been documented from the Cape Fear, Neuse, Tar-Pamilico, Roanoke, and Chowan River basins.

Distribution by County: Waccamaw River Basin: Columbus Co. (Waccamaw River Basin, including Lake Waccamaw canals). Black River Basin: Pender Co. (Black River); Bladen Co. (Black River); Sampson Co. (Six Runs Creek Subbasin). Neuse River Basin: Wake Co. (Middle and Swift creek subbasins); Johnston Co. (Middle and Swift creek subbasins); Jones Co. (Trent River). Tar-Pamlico River Basin: Edgecombe Co. (Tar River, Swift Creek Subbasin); Nash Co. (Tar River, Swift Creek Subbasin); Franklin Co. (Sandy Creek Subbasin); Halifax Co. (Fishing Creek Subbasin); Warren Co. (Fishing Creek Subbasin). Chowan River Basin: Gates Co. (Chowan River); Chowan Co. (Chowan River). NOTE: All headwater areas that flow into these occupied habitats should receive special management.

Habitat Preferences
The eastern lampmussel is usually found in medium to coarse sands.

Life History
The eastern lampmussel is a bradytictic breeder. Ortmann (1919) found that the breeding season extends from August to the following August. Fish hosts are unknown.