Pyrgulopsis archimedis
Pyrgulopsis archimedis, commonly known as the archimedes pyrg, is a species of small freshwater snails with an operculum, aquatic gastropod molluscs or micromolluscs in the family Hydrobiidae.
This species' natural habitat is rivers and lakes. It is endemic to the Upper Klamath Lake and the uppermost portion of the Link River near Algoma, Oregon, United States.