Bostryx anomphalus H.A. Pilsbry, 1944
Vermiculatus anthisanensis (L. Pfeiffer, 1853)
Vermiculatus anthisanensis subfasciatus (L. Pfeiffer, 1853)
Bulimus antidiluvianus (FOSSIL) J.L.M. Poiret, 1801 †
Bulimulus antiguensis A. Catlow & L.A. Reeve,1845
Drymaeus apicepunctatus H.B. Preston, 1914
Bulimulus apodemetes (A.V.M.D. D'Orbigny,1835)
Naesiotus approximatus W.H. Dall, 1900
Vermiculatus aquilus (L.A. Reeve, 1848)
Neopetraeus arboriferus (H.A. Pilsbry, 1898)
Neopetraeus arboriferus latistrigatus H.A. Pilsbry, 1898
Neopetraeus arboriferus obesus W.K. Weyrauch, 1967
Neopetraeus arboriferus paucistrigatus W.K. Weyrauch, 1967
Neopetraeus arboriferus rectistrigatus H.A. Pilsbry, 1898
Drymaeus arcuatostriatus (L. Pfeiffer, 1855)
Bostryx arcuatus A.S.H. Breure, 1978
Naesiotus arnaldoi (P.D. Lanzieri& H.E.B. Rezende, 1971)
Plicolumna artemisia (W.G. Binney, 1861)
Naesiotus asperatus J.A. Albers, 1857
Peronaeus atacamensis (L. Pfeiffer, 1856)
Neopetraeus atahualpa (W.L.H. Dohrn, 1863)
Aposcutalus atlanticus (A.V.C. Dutra-Clarke& J.L.M. Leme, 1985)
Mesembrinus attenuatus L. Pfeiffer, 1853
Mesembrinus attenuatus varicosus (L. Pfeiffer, 1851)
Drymaeus aurantiostomus F.G. Thompson& J.E. Deisler, 1982
Drymaeus aureolus R.J.L. Guppy, 1866
Scutalus aureus A.S.H. Breure, 1978
Mesembrinus aurifluus L. Pfeiffer, 1857
Drymaeus auris L. Pfeiffer, 1866
Cochlorina aurisleporis (J.G. Bruguière, 1789)
Cochlorina aurisleporis intensior H.A. Pilsbry, 1898
Cochlorina aurismuris S. Moricand, 1833
Drymaeus aurisratti R.A. Philippi, 1867
Cochlorina aurita (J.B. von Spix, 1827)
Naesiotus avellana (H.H. Beck, 1837)