A new hydrobiid from subterranean waters of the Timavo River (Friuli-Venetia Julia, NE. Italy) (Gastropoda Prosobranchia: Hydrobiidae)

A new hydrobiid species, “ Plagigeyeria” stochi, is described from subterranean waters of the Timavo River (Trieste, Italy). Because the new species is only known from shells, no definitive taxonomie statement can be made. Moreover, the two genera ( Lanzaia and Plagigeyeria) which have species with shells recalling that of the new species, are not well defined, due to the lack of anatomical data on most of the species assigned to them, particularly their type species.