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Note: Red text
is defined in the Glossary
Description
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
(see map)
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.
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