The Ochlockonee moccasinshell (Medionidus simpsonianus) is a species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae, the river mussels.
This species is endemic to the United States. Its natural habitat is rivers.
Medionidus simpsonianus was described as a species by Bryant Walker in 1905 in The Nautilus journal:
This article incorporates public domain text - a public domain work by Bryant Walker (1856-1936, U.S.A.) from reference.