Geltena meyeri (FOSSIL) R. Casey, 1961 †
Scissodesma micronitida (R. von Cosel, 1995)
Anatina millepunctata (FOSSIL) E.F. de Vogel, 1895 †
Mactra mississippiensis (FOSSIL) T.A. Conrad, 1848 †
Mactra mitis L.A. Reeve, 1854
Eastonia mitis (FOSSIL) C. Mayer, 1867 †
Mulinia modesta (P.P. Carpenter, 1864)
Mactromeris montereyana (FOSSIL) R. Arnold, 1908 †
Mactra mula (FOSSIL) J. Marwick, 1948 †
Mactromeris muliniaformis (FOSSIL) Wagner & Schilling,1923 †
Spisula murchisoni (L.A. Reeve, 1854)
Standella mystrosura (FOSSIL) J.D. Stilwell& Zinsmeister, 1992 †
Mactra nadali (FOSSIL) A.E.M. Cossmann& M.A. Peyrot, 1909 †
Mactromeris nagakoensis (FOSSIL) K.M. Hatai & S. Nisiyama,1949 †
Mactrotoma nasuta (Gould, 1851)
Meropesta nicobarica (J.F. Gmelin, 1791)
Crepispisula nigeriensis (FOSSIL) (Adegoke 1977) †
Mactra nipponica J.T. Kuroda& T. Habe in J.T. Kuroda & al., 1971
Scissodesma nitida (J.F. Gmelin, 1791)
Leptospisula nivea (J.F. Gmelin, 1791)
Mactra nucleiformis (FOSSIL) C. Mayer, †
Mactra nucleiformis duvergieri (FOSSIL) A.E.M. Cossmann& M.A. Peyrot, 1909 †
Tresus nuttallii (T.A. Conrad, 1837)
Lutraria oblonga (J.F. Gmelin, 1791)
Lutraria oblonga expansa (FOSSIL) G.F. Dollfus, Cotter& R. dos Santos Gomes, 1904 †
Mactra oblonga (FOSSIL) R.A. Philippi, 1887 †
Spisula obtruncata (FOSSIL) Woods, 1850 †
Mactra ochracea E.C. Von Martens, 1880
Cymbophora okadakensis (FOSSIL) Tamura, 1977 †
Mactra olorina R.A. Philippi, 1846
Mactra opposita L.A. Reeve, 1854
Mactra ordinaria (E.A. Smith, 1898)
Mactra orthogonalis (FOSSIL) Dufour, 1881 †
Pseudocardium orthomorpha (FOSSIL) Grant & H.R. Gale, 1931 †
Mulinia orthria (FOSSIL) Gardner 1928 †