Venericardia imbricata praeminenta (FOSSIL) Slodkevitch †
Cardiocardita inaequalis (FOSSIL) R.A. Philippi, 1887 †
Cyclocardia incisa (W.H. Dall, 1903)
Carditellopsis infans (E.A. Smith, 1885)
Pleuromeris inflatior (FOSSIL) †
Pleuromeris inflator (FOSSIL) †
Centrocardita inquinata (M. Nicklés, 1955)
Vimentum insignis (E.A. Smith, 1885)
Pleuromeris instata (FOSSIL) C.R. Laws, 1944 †
Goossensia irregularis (FOSSIL) (G.P. Deshayes, 1858 †)
Cyclocardia isaotakii (R. Tiba, 1972)
Venericardia isaurae (FOSSIL) C.J. Maury, 1924 †
Venericardia islahispaniolae (FOSSIL) C.J. Maury, 1917 †
Tutcheria itoi (FOSSIL) I. Hayami, 1969 †
Glans janjukiensis (FOSSIL) (A.C. Chapman& F.A. Singleton, 1927 †)
Megacardita japonica (FOSSIL) A. Mizuno, 1952 †
Cardita jenkinsi (FOSSIL) Smith, 1927 †
Venericor jewelli (FOSSIL) (Gardner, 1935 †)
Megacardita jouanneti (FOSSIL) (B. de Basterot, 1825 †)
Megacardita jouanneti bearnensis (FOSSIL) A.E.M. Cossmann& M.A. Peyrot, 1912 †
Megacardita jouanneti consobrina (FOSSIL) A.E.M. Cossmann& M.A. Peyrot, 1912 †
Coripia jozinae (J.J. Van Aartsen, 1985)
Cardita kalimnae (FOSSIL) G.B. Pritchard, 1903 †
Pleuromeris kapuaensis (FOSSIL) J. Marwick, 1931 †
Strophocardia karagiensis (FOSSIL) A.M. Popov, 1983 †
Cyclocardia kavranensis (FOSSIL) (Slodkewitsch, 1938 †)
Claibornicardia keenae (FOSSIL) (Verastegu, 1953 †)
Milneria kelseyi W.H. Dall, 1916
Ainicardita kevetscheveemensis (FOSSIL) (Slodkewitsch, 1936 †)
Cyclocardia kieli (FOSSIL) C. Nielsen, 2013 †
Venericor kilmacodes (FOSSIL) (Gardner & E. Bowles,1939 †)
Ainicardita kinkiliana (FOSSIL) (Slodkewitsch, 1936 †)
Cyclocardia kirkerensis (FOSSIL) Clark, 1918 †
Megacardita koreana T. Habe & K. Itô, 1965
Pleuromeris koruahinensis (FOSSIL) (J.A. Bartrum & Powell,1928 †)