Cardium hybridum (FOSSIL) G.P. Deshayes, 1829 † France, Paris Basin64 mm
Vasticardium hyllebergi N.N. Thach, 2014 Thailand, Phuket Island65,6 mm
Cardium hystericus (FOSSIL) von Schlotheim, 1820 †
Patagonicardium iheringi (FOSSIL) D. Frassinetti& Covacevich, 1999 † Chile, Puerto Guadal
Loxocardium impeditum (FOSSIL) (G.P. Deshayes, 1858 †) France, Paris Basin23 mm
Laevifulvia imperfecta E. Vidal & L. Kirkendale,2007 Philippines, Dinagat Island15,1 mm
Acrosterigma impolitum (G.B. II Sowerby, 1841) Australia, Port Hedland39 mm
Corculum impressum (J. Lightfoot, 1786) Philippines, Cebu48 mm
Cardium inaequalis (FOSSIL) Bell, 1893 † UK, England, East Sussex
Cardium inaequiconvexum (FOSSIL) A.E.M. Cossmann& G. Pissarro, 1927 † Pakistan, N.W.F.P., Kohat
Vepricardium incarnatum (L.A. Reeve, 1844) Philippines, Sulu Sea56 mm
Cardium incomptum E. Forbes, 1846
Cardium indicum J.B.P.A. Lamarck, 1818 Senegal, Dakar86,9 mm
Afrocardium infimum (FOSSIL) Gilbert, 1936 † Belgium
Lunulicardia insulare (FOSSIL) Reed, 1927 † UK, England, Herefordshire
Vasticardium insulare E. Vidal, 1997 Mozambique, Bazaruto Island72,8 mm
Cardium interruptum (FOSSIL) Woods, 1850 † UK, England, Norfolk
Cardium intersectum E. Forbes, 1846
Frigidocardium iris M. Huber& J.J. Ter Poorten, 2007 Philippines, Balicasag Island23,9 mm
Plagiocardium ishigakensis (FOSSIL) F.S. MacNeil, 1964 † Japan, Ishigaki
Microcardium islahispaniolae (FOSSIL) (C.J. Maury, 1917 †) Dominican Republic
Trachycardium isocardia (C. Linnaeus, 1758) South Australia60 mm
Nemocardium iwakiense (FOSSIL) J. Makiyama, 1934 † Western Kamchatka
Clinocardium iwasiroense (FOSSIL) S. Nomura, 1943 † Japan, Akita
Ciliatocardium iwatense (FOSSIL) (K. Chinzei, 1959 †) Japan, Iwate
Adacna jalpugensis (I. Borcea, 1926)
Microcardium jamaicense (FOSSIL) (W.H. Dall, 1903 †) Jamaica, Saint Thomas
Serripes japonica (FOSSIL) H. Noda, 1962 † Russia, Sakhalin
Schedocardia juncea (FOSSIL) A.A. Olsson, 1930 † Peru, Paita
Keenocardium kakertense (FOSSIL) (V.N. Sinelnikova,1990 †) Western Kamchatka
Hedecardium kanlenum (FOSSIL) (Cotter, 1923 †)
Integricardium keenae (FOSSIL) Marincovich Jr., 1993 † France, Aquitaine
Nemocardium keenae (FOSSIL) Renard, 1994 † France, Paris Basin35 mm
Vasticardium kenyanum (L.R. Cox, 1930) Thailand, Phuket77,3 mm
Acrosterigma kerslakae J.M. Healy& K.L. Lamprell, 1992 Australia, Broome34,7 mm