''Anodonta californiensis'', the California floater, is a species of freshwater

mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...

, an aquatic

bivalve Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bival ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the family

Unionidae The Unionidae are a family of freshwater mussels, the largest in the order Unionida, the bivalve molluscs sometimes known as river mussels, or simply as unionids. The range of distribution for this family is world-wide. It is at its most diverse ...

, the river mussels.

Description

''Anodonta californiensis'' have thin, elliptical shells and can reach a size of . They are very similar to ''A. nuttalliana'', and recent studies believe the two may actually be part of the same

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

. The two were thought to be distinguishable by the prominent dorsel wing which was lacking in the California floater.

Distribution

The range of the California floater may include Idaho, California, Utah, Washington, Arizona, Wyoming, Nevada, and Mexico. The exact range is unclear and may overlap with ''A. nuttalliana''.

References

californiensis Bivalves described in 1852 {{bivalve-stub