The rabbitsfoot (''Theliderma cylindrica'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

freshwater mussel Freshwater bivalves are one kind of freshwater mollusc, along with freshwater snails. They are bivalves that live in fresh water as opposed to salt water, which is the main habitat type for bivalves. The majority of species of bivalve molluscs ...

. It is 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. This species is native to the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, where it is widespread in the drainages of the

Ohio River The Ohio River is a long river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing southwesterly from western Pennsylvania to its mouth on the Mississippi River at the southern tip of Illino ...

and the

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lakes ...

. It has disappeared from over half its historic range.

Subspecies

Two subspecies have been described. It is unclear whether they represent distinct evolutionary lineages, or are merely

ecophenotypic variation Ecophenotypic variation ("ecophenotype") refers to phenotypical variation as a function of life station. In wide-ranging species, the contributions of heredity and environment are not always certain, but their interplay can sometimes be determine ...

which would not warrant any taxonomic status. A 2007 genetic study has cast doubt upon the validity of the existence of two subspecies. * ''Theliderma cylindrica cylindrica'' (Say, 1817) — * ''Theliderma cylindrica strigillata'' (Wright, 1898) — Rough rabbitsfoot, found only in the headwaters of the

Tennessee River The Tennessee River is the largest tributary of the Ohio River. It is approximately long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names, ...

References

Endemic fauna of the United States cylindrica Bivalves described in 1817 {{Unionidae-stub

Subspecies

See also

References