Vitrinella anomala (A.V.M.D. D'Orbigny,1842)
Tornus anselmoi E. Rolán & F. Rubio, 2002
Circulus anthera (FOSSIL) Gardner, 1947 †
Solariorbis antillensis D. De Jong & H.E. Coomans,1988
Cyclostremiscus anxius (C. Hedley, 1910)
Discopsis apertus E. Rolán & F. Rubio, 2002
Tornus aquitanicus (FOSSIL) P. Lozouet, 1998 †
Vitrinorbis arabscripta E. Rolán & F. Rubio, 1996
Anticlimax arifca (P. Bartsch, 1915)
Vitrinella aristata F. Rubio, R. Fernández-Garcés& E. Rolán, 2011
Solariorbis arnoldi P. Bartsch, 1927
Vitrinella assimilis K.H.J. Thiele, 1925
Pseudoliotia asteriscus (A.A. Gould, 1859)
Anticlimax athleenae (H.A. Pilsbry& J.T.L. McGinty, 1946)
Teinostoma atomaria (C.B. Adams, 1861)
Tornus attenuatus E. Rolán & F. Rubio, 2002
Tornus aupouria (A.W.B. Powell, 1937)
Circulus aurelius (FOSSIL) (Orbigny, 1850 †)
Teinostoma austinense (FOSSIL) Stanton, 1947 †
Teinostoma avunculus (FOSSIL) H.A. Pilsbry, 1953 †
Pseudoliotia axialis C.F. Laseron, 1958
Tornus axiotimus (J.C. Melvill & R. Standen,1895)
Teinostoma azoricum (P. Dautzenberg& H. Fischer, 1896)
Cyclostremiscus azuerensis H.A. Pilsbry & A.A. Olsson,1952
Panastoma azulense H.A. Pilsbry & A.A. Olsson,1945
Solariorbis bailyanus H.A. Pilsbry & A.A. Olsson,1952
Cyclostremiscus bailyi (L.G. Hertlein& A.M. Strong, 1951)
Solariorbis bakeri (A.M. Strong& L.G. Hertlein, 1939)
Cyclostremiscus balboa H.A. Pilsbry & A.A. Olsson,1945
Teinostoma baldingeri F. Rubio, R. Fernández-Garcés& E. Rolán, 2011
Cyclostremiscus baldridgae (P. Bartsch, 1911)
Pleuromalaxis balesi (H.A. Pilsbry& J.T.L. McGinty, 1945)
Idioraphe barryi (FOSSIL) LeBlanc, 1942 †
Cyclostremiscus bartschi (W.C. Mansfield, 1936)
Cyclostremiscus basicostatus (FOSSIL) B.M. Landau, F. Da Silva& S.M. Heitz, 2016 †