Ciliatocardium carlsbergianum (FOSSIL) A.I. Kafanov, 2002 †
Acanthocardia carolimartini (FOSSIL) C. Beets, 1985 † Indonesia, Junghuhn
Trigoniocardia carolinae (FOSSIL) C.J. Maury, 1912 † Trinidad and Tobago, Siparia
Granocardium carolinum (FOSSIL) (A.V.M.D. D'Orbigny,1843 †) Egypt, Sinai Peninsula
Trachycardium carpati (M. Nicklés, 1955) Senegal, Dakar48 mm
Parvicardium carrozzai J.J. Van Aartsen& J. Goud, 2001 Turkey, Bozcaada Island6 mm
Nemocardium carteri (FOSSIL) P.A. Maxwell, 1992 † New Zealand
Monodacna caspia (K.E.I. von Eichwald,1829) Black Sea17,6 mm
Laevicardium castanea E. Vidal, 2005 Italy, Livorno29,6 mm
Pratulum catinus (FOSSIL) (P.A. Maxwell, 1992 †) New Zealand
Neodidacnomya caucasica (FOSSIL) (Andrussov, 1923 †)
Dinocardium cedrelarum (FOSSIL) (L.R. Cox, 1941 †) Costa Rica, Puntarenas120 mm
Keenaea centifilosum (Carpenter, 1864) Oregon9,2 mm
Frigidocardium centumliratum (J.C. Melvill, 1907) La Reunion Island24,6 mm
Phlogocardia cestum (FOSSIL) (W.H. Dall, 1903 †) Florida14 mm
Keenocardium chejsliensis (FOSSIL) (V.N. Sinelnikova,1990 †) Russia, Sakhalin
Acanthocardia cheribonense (FOSSIL) C.H. Oostingh, 1935 † Indonesia
Cerastoderma chipolanum (FOSSIL) W.H. Dall, 1900 † Florida50 mm
Cerastoderma chipolanum alumen (FOSSIL) J. Gardner, 1928 † Florida43 mm
Ciliatocardium ciliatum (O. Fabricius, 1780) Taiwan Strait70 mm
Agnocardia cinderellae (FOSSIL) (C.J. Maury, 1917 †) Dominican Republic58 mm
Cardium citrinoideum (FOSSIL) B. Phillips, 1829 † UK, England, North Yorkshire
Agnocardia claibornense (FOSSIL) (T.H. Aldrich, 1911 †) Florida
Laevicardium clarionense (L.G. Hertlein& A.M. Strong, 1947) Panama, Chiriqui Bay
Cardium cloacinum (FOSSIL) F.A. von Quenstedt,1856 †
Cardium cognatum (FOSSIL) Phillips, 1829 † UK, England, North Yorkshire
Cardium coislinense (FOSSIL) A.E.M. Cossmann, 1905 † France, Brittany6 mm
Hedecardium collinsi (FOSSIL) J. Marwick, 1960 † New Zealand, Canterbury, Waimate
Fulvia colorata E. Vidal & L. Kirkendale,2007 Philippines, Masbate Island17,1 mm
Monodacna colorata (K.E.I. von Eichwald,1829) Black Sea19,3 mm
Monodacna colorata acuticostata B.M. Logvinenko& Y.I. Starobogatov Caspian Sea13 mm
Americardia columba (A. Heilprin, 1886) Florida33 mm
Americardia columbella Y.C. Lee & M. Huber, 2012 Florida, Sanibel Island
Laevicardium compressum (FOSSIL) W.H. Dall, 1900 † Florida23 mm
Vasticardium compunctum T. Kira, 1959 Okinawa48 mm