Paradacna abichi (FOSSIL) Hornes †
Agnocardia acrocome (FOSSIL) (W.H. Dall, 1900 †)
Acanthocardia aculeata (C. Linnaeus, 1758)
Cardium acutangulum (FOSSIL) Phillips, 1829 †
Chesacardium acutilaqueatum (FOSSIL) (T.A. Conrad, 1839 †)
Lyrocardium aeolicum (I. von Born, 1778)
Microcardium aequiliratum J. Poutiers, 1981
Ciliatocardium ainuanum (FOSSIL) (Yokoyama, 1927 †)
Monodacna albida (B.M. Logvinenko& Y.I. Starobogatov, 1967)
Protocardia alcesiana (FOSSIL) McLearn, 1933 †
Trigoniocardia aliculum (FOSSIL) W.H. Dall, 1900 †
Cardium altavillense (FOSSIL) A.E.M. Cossmann & G. Pissarro †,
Agnocardia alternata (FOSSIL) (Hubbard, 1920 †)
Cardium altum E. Forbes, 1846
Iheringicardium ameghinoi (FOSSIL) (H.F.A. von Ihering,1907 †)
Trigoniocardia aminensis (FOSSIL) W.H. Dall, 1900 †
Acrosterigma amirante E. Vidal, 1999
Lyrocardium anaxium P.G. Oliver& H.C.G. Chesney, 1997
Nemocardium angelinae (FOSSIL) Garvie, 2013 †
Vasticardium angulatum (J.B.P.A. Lamarck, 1819)
Cardium angustatum (FOSSIL) J. de C. Sowerby, 1821 †
Lophocardium annettae (W.H. Dall, 1889)
Trigoniocardia antillarum (A.V.M.D. D'Orbigny,1853)
Vepricardium antiquum (FOSSIL) (N.H. Ludbrook, 1978 †)
Pratulum antisemigranulatum (FOSSIL) (McCoy, 1877 †)
Fulvia aperta (J.G. Bruguière, 1789)
Discors aquitanicus (FOSSIL) C. Mayer, 1858 †
Pseudofulvia arago E. Vidal & L. Kirkendale,2007
Keenocardium arakawae (FOSSIL) (Kamada 1962) †
Vasticardium arenicola (FOSSIL) (L.A. Reeve, 1845 †)
Clinocardium asagaiense (FOSSIL) (J. Makiyama, 1934 †)
Vepricardium asiaticum (J.G. Bruguière, 1789)
Papyridea aspersa (G.B. I Sowerby, 1833)
Vepricardium asperulum (FOSSIL) (J.B.P.A. Lamarck,1805 †)
Vasticardium assimile (L.A. Reeve, 1844)