California Floater Mussel

The California floater (Anodonta californiensis) is a freshwater mussel native to low-gradient, slow-moving water from Southern California and Arizona to British Columbia. The species is one of five freshwater mussels in North America and can be identified by an ellipsoidal to trapezoid-ovate shell shape with a yellow to brown-black outer surface, white inner shell, and blue-purple tinted flesh. These mussels prefer sandy and muddy bottoms where they filter feed on a variety of items, including plankton, bacteria, and algae. Compared to other western mussel species, the California floater is considered short-lived and fast-growing, reaching maturity around five years of age with a lifespan of up to 15 years. Like other native western North American mussels, the California floater is imperiled throughout much of its range due to pollution, habitat fragmentation, and the loss of their host fishes from their native range.

Fun Fact: Like many other mussel species, California floaters require a compatible fish host to complete their life cycle, during which their embryos parasitize the gills of the fish host.