Medionidus acutissimus (Lea, 1831)
5 synonyms | 1 specimen
Range: Mobile and Choctawhatchee basins, eastern Gulf Coastal Plain, USA. [North America]
Genbank sequences: 16S, 5.8S, COI, ITS1, ND1.
IUCN Red List: Endangered.
Nature Serve: G2 Threatened.
Other web sites: ITIS MolluscaBase.

Medionidus conradicus (Lea, 1834)
6 synonyms | 1 specimen
Range: Tennessee and Cumberland rivers, USA. [North America]
Genbank sequences: 16S, 28S, 5.8S, COI, ITS1, ND1.
IUCN Red List: Lower Risk/near threatened.
Nature Serve: G3 Proposed endangered.
Other web sites: ITIS MolluscaBase.

Medionidus parvulus (Lea, 1860)
1 synonym | 1 specimen
Range: Coosa River, Alabama, Georgia, and Tennessee, USA. [North America]
IUCN Red List: Endangered.
Nature Serve: G1? Endangered.
Other web sites: ITIS MolluscaBase.

Medionidus penicillatus (Lea, 1857)
2 synonyms | 2 specimens
Range: Apalachicola and adjacent rivers, Alabama, Georgia, and Florida, USA. [North America]
Genbank sequences: COI, ND1.
IUCN Red List: Critically Endangered.
Nature Serve: G2 Endangered.
Other web sites: ITIS MolluscaBase.

Medionidus simpsonianus Walker, 1905
1 synonym | 1 specimen
Range: Endemic to the Ochlockonee Basin, eastern Gulf Coastal Plain, Florida and Georgia. [North America]
IUCN Red List: Critically Endangered.
Nature Serve: G1 Endangered.
Other web sites: ITIS MolluscaBase.

Medionidus walkeri (B.H. Wright, 1897)
1 synonym | 2 specimens
Range: Suwannee and Hillsborough rivers, Florida. [North America]
IUCN Red List: Critically Endangered.
Nature Serve: G1 Threatened.
Other web sites: ITIS MolluscaBase.

Medionidus senectus (White, 1877) (Cretaceous)
1 synonym | 0 specimens
Range: Cretaceous, North America.
Other web site: MolluscaBase.