The appearance of distinct stripes on the zebra mussel shell is often used as a character for identification. However, there is considerable variation in the coloration pattern of zebra mussels, and hence its species name polymorpha. Color variation can range from being almost completely black to fairly uniform light brown in coloration.
This photograph shows the various stripe and coloration patterns that can be present on the shell of the zebra mussel.
Adult Identification Information
Zebra Mussel Identification