Their minute shell is often colored. They are characterized by a calcareous operculum, a lobe on the upper surface of the neck. The ctenidium, the respiratory gill-comb, is very broad. They have a ciliary feeding habit. The kidney has a large extension towards the mantle.[3]
^Lilly, M.M. (1953). "The mode of life and the structure and functioning of the reproductive ducts of Bithynia tentaculata (L.)". Proceedings of the Malacological Society of London. 30 (4–5): 87–110.
^ abGlöer P. (2002). Die Süßwassergastropoden Nord- und Mitteleuropas. Die Tierwelt Deutschlands, ConchBooks, Hackenheim, 326 pp., ISBN3-925919-60-0. Reference for subgenera of genus Bithynia.
^(in Russian) Lazutkina E. A., Andreyeva S. I. & Andreyev N. I. (2010). " [Boreoelona sibirica (Westerlund, 1886) (Gastropoda, Pectinibranchia, Bithynidae) in the waterbodies of Western Siberia and Middle Urals]". Ruthenica20(2): 103-108. PDFArchived 2020-07-13 at the Wayback Machine
^Glöer P. & Pešić V. (2006). "On the identity of Bithynia graeca Westerlund, 1879 with the description of three new Pseudobithynia n. gen. species from Iran and Greece (Gastropoda: Bithyniidae)". Malakologische Abhandlungen24: 29-36. Dresden. PDF.