Pagodula occidua B.A. Marshall & R. Houart,2011
Ocenebra occitanica (FOSSIL) A.E.M. Cossmann& M.A. Peyrot, 1923 †
Typhinellus occlusus (T.A. Garrard, 1963)
Pascula ochrostoma (H.M.D. de Blainville,1832)
Xanthochorus ochuroma (FOSSIL) DeVries, 2005 †
Murexsul octagonus (J.R.C. Quoy& J.P. Gaimard, 1834)
Muricopsis octogonatus (FOSSIL) (J.R.C. Quoy& J.P. Gaimard, 1833 †)
Murexsul octogonus (J.R.C. Quoy& J.P. Gaimard, 1833)
Phyllonotus oculatus (L.A. Reeve, 1845)
Abyssotrophon odisseyi (A.N. Golikov& B.I. Sirenko, 1992)
Daphnellopsis ogormani (FOSSIL) (A.E.M. Cossmann †)
Trophon ohlini H. Strebel, 1904
Coralliophila ohmurai S. Kosuge, 1985
Boreotrophon okhotensis R.V. Egorov, 1993
Reishia okutanii Thach, 2016
Babelomurex oldroydi (I.M. Oldroyd, 1929)
Vaughtia olivemeyerae M. Lussi, 2012
Paziella oliverai (S. Kosuge, 1984)
Dermomurex olssoni E.H. Vokes, 1989
Vokesimurex olssoni (E.H. Vokes, 1967)
Eupleura olssoni (FOSSIL) E.H. Vokes, 1989 †
Typhina olssoni (FOSSIL) A.M. Keen, 1943 †
Aspella omanensis Houart,Gori & Rosado, 2017
Muricopsis omanensis K.R. Smythe & P.G. Oliver,1986
Morula oparensis (J.C. Melvill, 1912)
Dicathais orbita (J.F. Gmelin, 1791)
Dicathais orbita aegrota (L.A. Reeve, 1846)
Dicathais orbita textilosa (J.B.P.A. Lamarck, 1822)
Chicoreus orchidiflorus (T. Shikama, 1973)
Coralliophila orcuttiana W.H. Dall, 1919
Paziella oregonia H.R. Bullis, 1964
Orania ornamentata R. Houart, 1995
Trophonopsis orpheus (A.A. Gould, 1849)
Attiliosa orri (W.O. Cernohorsky, 1976)
Calotrophon ostrearum (T.A. Conrad, 1846)