Classification: State Extirpated
Female Interior
Female Exterior
Male Interior
Male Exterior
NOTE: Hover over the bold words for definitions or see the Glossary.
This species was described by Isaac Lea in 1834 from the Cumberland River in Tennessee. The oyster mussel is a small species (adults 50 - 70 mm) that exhibits pronounced sexual dimorphism (male and female shells differ in form). The periostracum is yellowish-green with numerous narrow green rays, and the nacre is bluish-white to creamy in color. Male shells are elliptical in shape; while, female shells have a swollen posterior end that is dark green in color. The species has two lateral teeth in the left valve and one lateral tooth in the right valve. Two small pseudocardinal teeth are present in each valve.
Shell Anatomy
Historic Distribution in North Carolina: French Broad River
This species is a bradytictic breeder. Spawning occurs in late summer, and gravid females have been observed in May through July. Females have been observed lying on top of the substrate while displaying soft parts. Identified fish host species include spotted, redline and dusky darters, and banded sculpin.
General Life History For Mussels