Classification: Federal and State Endangered
NOTE: Hover over the bold words for definitions or see the Glossary.
This species was described by Isaac Lea in 1838 from the Stones River in Tennessee. The little-wing pearlymussel is one of the smallest freshwater mussel species: adults rarely exceed 35 mm in length. The species' name is descriptive of its wing-like appearance.
The periostracum is usually eroded, giving the shell a chalky or ashy white appearance. When the periostracum is present, the shell is light green or dark yellowish brown with dark rays of variable width along the shell's anterior surface. The nacre is whitish on the anterior border and salmon or flesh colored in the beak cavity. Lateral teeth are short, vestigial, or entirely absent. The left valve has an irregular triangular pseudocardinal tooth, sometimes with the vestige of another tooth in front of it, and the right valve has a single triangular pseudocardinal tooth. This species is sexually dimorphic.
photo by Dick Biggins
Gravid females of this species have been reported in September and October suggesting that the little-wing pearlymussel is bradytictic breeder, holding glochidia from mid-summer through the following spring. Fish reported as hosts for this species include greenside and emerald redline darters. Based on field observations, banded sculpin and redline darter also may serve as host species because they have been observed under large flat rocks and on gravel shoals where little-wing pearlymussels are known to occur.
General Life History For Mussels