Classification: State Threatened
NOTE: Hover over the bold words for definitions or see the Glossary.
The shell of the rainbow is roughly elliptical in shape. There is slight sexual dimorphism in shell shape with males becoming more pointed posteriorly; while, females have a broader and rounder posterior end to accommodate the marsupium. The periostracum is golden brown with both broad and narrow green rays over the entire surface of the shell. Nacre color is variable including white with a salmon wash in the beak cavity to pink, salmon, or purple. The nacre of the posterior end is often iridescent. There are two triangular pseudocardinal teeth and two blade-like lateral teeth in the left valve. The right valve has only one pseudocardinal tooth and one lateral tooth. (Parmalee and Bogan 1998)
General Life History For Mussels