Pyrgulopsis olivacea (Pilsbry, 1895) Marstonia olivacea, common name the olive marstonia, was a species of very small freshwater snail, an aquatic gastropod mollusc in the family Hydrobiidae.

This species was endemic to Alabama, the United States.

[1] Its natural habitat was rivers.

[1] This species is now extinct.

This Hydrobiidae-related article is a stub.