Pyrgula annulata
Introduction '''''Pyrgula annulata''''' is a species of freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae. ''Pyrgula annulata'' is the type species of the genus ''Pyrgula''.
Distribution This species occurs in Switzerland, Italy, Croatia, and Albania.
References
External links *  AnimalBase info* black and white drawings of shell:** Adams H. & Adams A. 1858. ''The genera of recent Mollusca: arranged according to their organization''. plate 32 figure 7. ** Call R. E. & Pilsbry H. A. 1886. ''On Pyrgulopsis, a new genus of rissoid mollusk, with description of two new forms''. Proceeding Davenport Academy of Natural Sciences, volume V., page  9-14.Plate II., figures 11-12.