Classification: Federal and State Endangered
NOTE: Hover over the bold words for definitions or see the Glossary.
In 1830, Isaac Lea (see Conrad illustration) described the dwarf wedgemussel. The name is appropriate as shells rarely exceed 45 mm in length. Clean young shells are usually greenish-brown with green rays. As the animal ages, the shell color becomes obscured by diatoms or mineral deposits and appears black or brown. The shell is thin but does thicken somewhat with age, especially toward the anterior end. The anterior end is rounded while the posterior end is angular forming a point near the posterio-ventral margin. The ventral margin is only slightly curved. The nacre is bluish-white, appearing whiter in the thickened anterior end. The most distinctive shell character of the dwarf wedgemussel is the arrangement of the lateral teeth. There are two lateral teeth in the right valve and one in the left valve. The typical arrangement for most freshwater mussel species consists of two lateral teeth in the left valve and one in the right valve. The incurrent and excurrent apertures and their associated papillae are usually white. The foot and other organs are also white.
Conrad Mussell Illustration
General Life History For Mussels
Conservation Plan for Five Rare Aquatic Species Restricted to the Neuse and Tar-Pamlico River Basins in North Carolina - 2020 (~6 MB PDF)