Eastern Pondmussel
Scientific Name: Ligumia nasuta
Classification: State Threatened
Photo Credit: NCWRC
Shells of the eastern pondmussel are elongate and look somewhat like the yellow lance (Elliptio lanceolata); however, the eastern pondmussel appears to have more height relative to length than the yellow lance. The periostracum is dark brown with fine rays visible on the posterior half of the shell. The posterior ridge is distinct and angular. The posterior slope is concave toward the umbos and tends to become convex toward the posterior end of the shell. The umbos are low and extend only slightly above the hinge line. The nacre is an iridescent blue to salmon color. Two pseudocardinal teeth are located in each valve. The left valve has two long, straight lateral teeth and the right valve has one lateral tooth. Papillae are located along the posterior half of the mantle.
Distribution
Cape Fear River Basin north to the St. Lawrence River Basin, Canada and westward through the northern parts of the Interior Basin. In North Carolina, this species is known from the Chowan, Roanoke, and Cape Fear river basins. The species has been recently extirpated from the Pamlico River Basin.
Distribution by County: Chowan River Basin: Hertford Co. (Meherrin River, Chowan River); Gates Co. (Chowan River). Roanoke River Basin: Washington Co. (Roanoke River). Cape Fear River Basin: Brunswick Co. (Rices Creek Subbasin). NOTE: All headwater areas that flow into these occupied habitats should receive special management.
Habitat Preferences
This species is found in silts and sands in areas with limited currents such as in lakes, ponds, and protected areas of rivers and creeks (Johnson 1970). Bill Adams and Andy Gerberich (personal communication) found this species in a course sand substrate with significant amounts of fine organic matter. Also in the area were occasional patches of fragrant waterlily (Nympaea odorata) and spatterdock (Nuphar luteum).
Life History
Ortmann (1919) considers the eastern pondmussel to be a bradytictic species with the breeding season extending from August until the following June. Gravid females are found in North Carolina during the cooler months of the year.
General Life History for Mussels
Shell Anatomy
