Fat Pocketbook

This species is characterized by very inflated or globose valves, thin and relatively fragile in structure when compared to other species. The anterior end is broadly rounded and angular near the hinge; posterior margin is narrow and rounded. Beaks are full, rounded, and high. Beak cavity is very deep and large. Periostracum is smooth, yellow to brown in color, sometimes with narrow yellow bands parallel to growth lines. Valves do not close perfectly on each other, but gape anteriorly and posteriorly. Nacre color is bluish-white, occasionally light pink inside the pallial line. Nacre often iridescent with bluish border. The approximate length of the fat pocketbook is to 5 inches.

The fat pocketbook prefers sand, mud, and fine gravel bottoms of large rivers.  It buries itself in these substrates in water up to eight inches deep. This mussel requires a stable, undisturbed habitat and sufficient population of fish hosts to complete the  mussels larval development.  

Today the fat pocketbook mussel is found only in the lower Wabash and Ohio rivers, and the lower Cumberland river.  Much of the mussels habitat is altered or destroyed by impoundments and dredging for irrigation, navigation, and flood control.  Other threats are caused by agricultural and industrial runoff.

Most of this information is provided by the U.S. Fish and Wildlife Service