Tropidophora sericea R.J. Griffiths& D.G. Herbert, 2013
Parachondria sericina (C.B. Adams, 1851)
Parachondria sericina retreatensis (H.B. Baker, 1934)
Parachondria sheppardiana (C.B. Adams, 1850)
Chondrothyretes shuttleworthi (L. Pfeiffer, 1851)
Chondrothyretes shuttleworthi portica (C. de la Torre& P. Bartsch, 1938)
Bermudezia sifontesi (C. de la Torre& P. Bartsch, 1941)
Parachondria silvatica G.T. Watters, 2016
Tudora similis J.E. Gray in G.B. Sowerby,1850
Chondropomorus simplex L. Pfeiffer
Opisthosiphon simpsoni P. Bartsch, 1946
Opisthosiphon simpsoni williamsae G.T. Watters & G. Duffy,2010
Torrellisca simpsoni J. Henderson & P. Bartsch,1920
Opisthocoelicum simulans C. de la Torre & P. Bartsch,1941
Turrithyra sinuosa (B.H. Wrightin L. Pfeiffer, 1862)
Turrithyra sinuosa hutia (C. de la Torre& P. Bartsch, 1938)
Turrithyra sinuosa rhachitica (C. de la Torre& P. Bartsch, 1938)
Turrithyra sinuosa vicina C. de la Torre & P. Bartsch,1938
Tropidophora socotrana (H.H. Godwin-Austen,1881)
Tropidophora socotrana serrulata E. Neubert, 2009
Chondropoma solidulum (J. Gundlachin L. Pfeiffer, 1860)
Chondropoma solidulum vitaense C. de la Torre & P. Bartsch,1938
Chondropoma solum P. Bartsch, 1946
Leiabbottella soluta (L. Pfeiffer, 1852)
Cyclostoma sordidum (J. Gundlach, 1857)
Opisthosiphon sosai C. de la Torre & P. Bartsch,1941
Abbottella sosuaensis (P. Bartsch, 1946)
Tropidophora soulaiana E. Fischer-Piette& A.M. Testud, 1973
Lithidion souleyetianum (S.A.A. Petit De La Saussaye, 1850)
Tropidophora sowerbyi L. Pfeiffer
Licina spencei G.T. Watters & G. Duffy,2010
Xenopoma spinosissimum C. de la Torre & P. Bartsch,1941
Annularia spinulosa C.B. Adams, 1849
Cyclotopsis spurca (J.P.S. Grateloup, 1839)
Cyclostoma squamosum (FOSSIL) M.A. Peyrot, 1933 †