Bostryx albicans (W.J. Broderip, 1832)
Bulimus albidus (FOSSIL) J.B.P.A. Lamarck, 1804 †
Drymaeus albolabiatus (E.A. Smith, 1877)
Mesembrinus albostriatus H. Strebel, 1882
Bostryx albus (G.B. I Sowerby, 1833)
Naesiotus alethorhytidus W.H. Dall, 1917
Drymaeus alsophilus R.A. Philippi, 1867
Drymaeus altenai A.S.H. Breure, 1976
Rabdotus alternatus (T. Say, 1830)
Rabdotus alternatus mariae J.A. Albers, 1850
Neopetraeus altoperuvianus (L.A. Reeve, 1849)
Neopetraeus altoperuvianus gracilior H.A. Pilsbry, 1898
Naesiotus altus (W.H. Dall, 1893)
Mesembrinus amandus (L. Pfeiffer, 1855)
Naesiotus amastroides C.M.F. Ancey, 1887
Drymaeus ambustus (L.A. Reeve, 1849)
Peronaeus ameghinoi H.F.A. von Ihering, 1908
Peronaeus ameghinoi madrynensis (A.V.M.D. D'Orbigny,1835)
Tocobaga americanus (FOSSIL) (A. Heilprin, 1886 †)
Drymaeus amoenus (L. Pfeiffer, 1847)
Peronaeus anachoreta L. Pfeiffer, 1856
Bostryx ancavilorum J.F. Araya, 2015
Drymaeus anceps J.A. Albers, 1854
Drymaeus andai F.P. Jousseaume, 1898
Mesembrinus andicola (L. Pfeiffer, 1847)
Naesiotus andivagus W.K. Weyrauch, 1956
Bostryx andoicus (P.M.A. Morelet, 1863)
Drymaeus angasi E.C. Von Martens, 1893
Bostryx angiportus H.A. Pilsbry, 1932
Newboldius angiportus W.K. Weyrauch, 1960
Scutalus angrandi P.M.A. Morelet, 1860
Drymaeus anguillensis L. Pfeiffer, 1865
Drymaeus angulobasis H.A. Pilsbry, 1944
Drymaeus angustus S.I. Da Costa, 1906
Drymaeus annulatus (L.A. Reeve, 1849)