Gyraulus rotundistomus (Sauerzopf, 1953 )
Gyraulus rotundostomus A. Nützel & K. Bandel,1993
Anisus rousianus (FOSSIL) (Noulet, 1854 †)
Hippeutis rouxi (FOSSIL) (Noulet, 1863 †)
Planorbarius royoi (FOSSIL) (P. Jodot, 1958 †)
Ferrissia ruandensis K.H.J. Thiele, 1911 Rwanda
Hebetancylus rugosa A.H. Clarke, 1980
Gyraulus rumanus W.A. Wenz in Krejci-Graf& W.A. Wenz, 1932
Gyraulus sabljari (Š. Brusina, 1892 )
Gyraulus sachsenhoferi (FOSSIL) M. Harzhauser & al.,2012 † Austria, Steiermark
Gyraulus saigonensis (J.C.H. Crosse& P.H. Fischer, 1863) Vietnam, Hanoi3,5 mm
Biomphalaria salinarum (P.M.A. Morelet, 1868) Angola
Ancylus sallei O. Böttger, 1857 Cuba
Laevapex sallei (J.R. Bourguignat, 1857) Veracruz, Mexico
Gyraulus saltensis J. Germain, 1922 India, Cuddalore
Menetus sampsoni C.M.F. Ancey, 1885 Illinois
Planorbarius sansaniensis (FOSSIL) (Noulet, 1854 †)
Anisus sarasinorum (Bohlinger, 1914) Indonesia
Ancylus saucatsensis (FOSSIL) M.A. Peyrot, 1932 (?) †
Gyraulus sauerzopfi T.A. Neubauer & al., 2015
Gundlachia saulcyana (J.R. Bourguignat, 1853) Venezuela
Ancylus scalariformis S. Stankovic& P. Radoman, 1953 Macedonia, Lake Ohrid
Bulinus scalaris R.W. Dunker, 1845 Central Africa
Planorbella scalaris (J.C. Jay, 1839) Florida25 mm
Gyraulus schamaricus Z.I. Izzatullaev, 1972 Tajikistan
Hippeutis schmackeri (S. Clessin, 1886) Korea, Pusan8 mm
Tropicorbis schmiererianus W.A. Biese, 1951 Chile, Coquimbo17 mm
Biomphalaria schrammi (J.C.H. Crosse, 1864) Costa Rica5 mm
Choanomphalus schrencki W. Dybowski, 1875 Lake Baikal, Russia
Choanomphalus schrenkii W. Dybowski, 1875
Drepanotrema schubarti (F. Haas, 1938) Brazil, Pernambuco4 mm
Steklovidiscus schulgae (FOSSIL) (Gozhik& Prysjazhnjuk, 1978 †)
Gyraulus scottianus G. Johnston, 1879 New South Wales
Gyraulus seibersdorfensis (Sauerzopf, 1953 )
Polypylis semiglobosa I.M. Moskvicheva in Dworiadkin, 1980 Russia, Sakhalin