Saccostrea glomerata (A.A. Gould, 1850)
Saccostrea glomerata commercialis (T. Iredale& T.C. Roughley, 1933)
Cubitostrea glucumarides (FOSSIL) C.J. Maury, 1924 †
Ostrea golfotristensis (FOSSIL) C.J. Maury, 1912 †
Ostrea grandicardinalis (FOSSIL) Vredenburg 1928 †
Conradostrea greeni (FOSSIL) Ward, 1992 †
Crassostrea gryphoides (FOSSIL) (Schlotheim, 1813 †)
Cubitostrea gudexi (FOSSIL) H.H. Suter, 1917 †
Lopha guppyi (FOSSIL) W.P. Woodring, 1925 †
Crassostrea guyanensis G. Ranson, 1967
Ostrea haleyi (FOSSIL) L.G. Hertlein, 1933 †
Crassostrea hatcheri (FOSSIL) H.F.A. von Ihering,1899 †
Flemingostrea haydeni (FOSSIL) A.E.M. Cossmann& G. Pissarro, 1927 †
Liostrea hebridica (FOSSIL) (E. Forbes, 1851 †)
Liostrea heteroclita (FOSSIL) (J.L.M. Defrancein G.P. Deshayes, 1832 †)
Ostrea hippopodium (FOSSIL) (S. Nilsson, 1827 †)
Ostrea hippopus (FOSSIL) R. Tate, 1886 †
Crassostrea hongkongensis D. Lam & B.S. Morton,2003
Ostrea hyotidoidea (FOSSIL) R. Tate, 1899 †
Lopha hyotiformis (FOSSIL) R.A. Philippi, 1901 †
Lopha imbricata J.B.P.A. Lamarck, 1810
Ostrea imputata H.E. Anton, 1838
Ostrea incisa (FOSSIL) Martin, 1883 †
Ostrea incurva (FOSSIL) Nilsson †
Crassostrea ingens (FOSSIL) (C.A. von Zittel, 1865 †)
Ostrea intermedoides (FOSSIL) T.H. Aldrich, 1921 †
Ostrea invalida (FOSSIL) White, 1887 †
Ostrea iridescens Gray, 1854
Ostrea jogjacartensis (FOSSIL) K. Martin, 1914 †
Lopha johnsoni (FOSSIL) (Aldrich 1886) †
Ostrea kansasensis (FOSSIL) Logan, 1899 †
Crassostrea kawauchidensis (FOSSIL) Tamura, 1977 †
Saccostrea kegaki K. Torigoe & A. Inaba,1981
Ostrea khamirensis (FOSSIL) Cox, 1936 †
Crassostrea lamellosa (FOSSIL) Azzaroli, 1958 †