Cyprimeria alta (FOSSIL) T.A. Conrad, 1875 †
Dosinia alta (R.W. Dunker, 1849)
Gouldia alta (FOSSIL) W.H. Dall, 1903 †
Lamelliconcha alternata (W.J. Broderip, 1835)
Dosinia altior G.P. Deshayes, 1853
Pitar altoumbonatum (FOSSIL) (T. Nagao, 1928 †)
Placamen altum (G.B. II Sowerby, 1853)
Lirophora alveata (FOSSIL) (T.A. Conrad, 1831 †)
Paphia amabilis R.A. Philippi, 1847
Dosinia amamiensis (T.A. Okutani, 2005)
Chionopsis amathusia (R.A. Philippi, 1844)
Chionopsis amathusia jamaniana H.A. Pilsbry & A.A. Olsson,1941
Chione ambigua (FOSSIL) (G. Rovereto, 1900 †)
Transenpitar americana (M. Doello-Juradoin A. Carcelles, 1951)
Dorisca amica (E.A. Smith, 1885)
Dorisca amica nana (J.C. Melvill, 1898)
Dosinia amphidesmoideas (FOSSIL) (Reeve 1850) †
Dosinia amphidesmoides (L.A. Reeve, 1850)
Petricola amygdalina G.B. I Sowerby, 1834
Tivelina analoga (FOSSIL) (G.P. Deshayes, 1857 †)
Venus analoga E. Forbes, 1846
Venus anceps (FOSSIL) G.P. Deshayes, 1857 †
Callista ancisa (FOSSIL) J. Marwick 1938 †
Chionopsis angelana (FOSSIL) (E.M. Spieker, 1922 †)
Pitar angelinae (FOSSIL) G.F. Harris, 1919 †
Petricola angolensis R. von Cosel, 1995
Transennella angulifera (G.B. II Sowerby, 1851)
Dosinia anguloides (FOSSIL) S. Nomura, 1935 †
Dosinia angulosa (R.A. Philippi, 1847)
Katherinella angustifrons (FOSSIL) (T.A. Conrad †)
Lioconcha annettae K.L. Lamprell& T. Whitehead, 1990
Callista annexa (FOSSIL) T.A. Conrad, 1865 †
Venerupis anomala (J.B.P.A. Lamarck, 1818)
Lamelliconcha anona (FOSSIL) A.A. Olsson, 1942 †
Eurhomalea antarctica (FOSSIL) (Sharman & R.B. Newton,1897 †)