Cavellia serpentinula (H.H. Suter, 1891)
Therasiella serrata R.A. Cumber, 1967
Setomedea seticostata (C. Hedley, 1924)
Helenoconcha sexdentata unknown
Ptychodon skottsberg N.H. Odhner, 1921
Rotadiscus smithae (R.K. Dell, 1954)
Allodiscus smithi H.H. Suter, 1894
Coenocharopa sordidus J. Stanisic, 1990
Penescosta sororcula (H.B. Preston, 1913)
Allodiscus southlandicus B.A. Marshall & G.M. Barker,2008
Mocella spelaeus (F.M. Climo, 1971)
Roblinella speranda T. Iredale, 1937
Allodiscus spiritus A.W.B. Powell, 1952
Pseudohelenoconcha spurca (G.B. Sowerby, 1844)
Reticulapex stanisici K.C. Emberton& R.J. Griffiths, 2009
Cavellia sterkiana (H.H. Suter, 1891)
Flammoconcha stewartensis R.K. Dell, 1952
Phacussa stewartensis (P. David, 1934)
Aeschrodomus stipulatus (L.A. Reeve, 1852)
Cralopa stroudensis (J.C. Cox, 1864)
Charopinesta suavis T. Iredale, 1944
Reticulapex subangulatus K.C. Emberton & T.A. Pearce,2000
Cavellioropa subantialba (H.H. Suter, 1890)
Chaureopa subdepressa F.M. Climo, 1985
Thermia subincarnata (H.H. Suter, 1894)
Cavellia subinfecta (H.H. Suter, 1899)
Luinodiscus sublesta (W.H. Benson, 1853)
Dentherona subrugosa (C.M.D.E. Legrand, 1871)
Mitodon suteri (R. Murdoch & H.J. Finlay,1923)
Cavellia sylvia (F.W. Hutton, 1883)
Trachycystis sylvicola A.C. van Bruggen& B. Verdcourt, 1965
Sinployea taipara F.J. Brook, 2010
Rotadiscus takakaensis (F.M. Climo, 1981)
Pilula talatai K.C. Emberton, 1994
Pernagera tamarensis (W.F. Petterd, 1879)