• Aclisina striatula (de Koninck, 1843) †
• Acremodonta crassicosta (A. W. B. Powell, 1937)
• Acremodontina alazon (Hedley, 1905)
• Acremodontina atypica (A. W. B. Powell, 1937)
• Acremodontina balcombiana B. A. Marshall, 1995 †
• Acremodontina boucheti B. A. Marshall, 1995
• Acremodontina carinata (A. W. B. Powell, 1940)
• Acremodontina kermadecensis B. A. Marshall, 1995
• Acremodontina magna B. A. Marshall, 1995
• Acremodontina maxwelli B. A. Marshall, 1995 †
• Acremodontina poutama (E. C. Smith, 1962)
• Acremodontina simplex (A. W. B. Powell, 1937)
• Acremodontina translucida (May, 1915)
• Acremodontina varicosa B. A. Marshall, 1995
• Addisonia brophyi J. H. McLean, 1985
• Addisonia enodis Simone, 1996
• Addisonia excentrica (Tiberi, 1855)
• Adeuomphalus ammoniformis G. Seguenza, 1876
• Adeuomphalus axistriatus Hoffman, Gofas & Freiwald, 2020
• Adeuomphalus bandeli (Schröder, 1995) †
• Adeuomphalus collinsi Kano, Chikyu & Warén, 2009
• Adeuomphalus crenulatus (A. W. B. Powell, 1937)
• Adeuomphalus curvistriatus Hoffman, Gofas & Freiwald, 2020
• Adeuomphalus densicostatus (Jeffreys, 1884)
• Adeuomphalus diegoalejandroi Fernández-Garcés, Rubio & Rolán, 2019
• Adeuomphalus elegans Kano, Chikyu & Warén, 2009
• Adeuomphalus guillei Kano, Chikyu & Warén, 2009
• Adeuomphalus misaeli Fernández-Garcés, Rubio & Rolán, 2019
• Adeuomphalus orientalis (Thiele, 1925)
• Adeuomphalus sinuosus (Sykes, 1925)
• Adeuomphalus trochanter Warén & Bouchet, 2001
• Adeuomphalus valentinae Fernández-Garcés, Rubio & Rolán, 2019
• Adeuomphalus xerente Absalão, 2009
• Aechmospira norma X.-D. Qiao, 1983 †
• Aenigmabonus kurilokamtschaticus Moskalev, 1978
• Aequispirella bifurcata (P. A. Maxwell, 1992) †
• Aequispirella corula (F. W. Hutton, 1885)
• Aequispirella enderbyensis (A. W. B. Powell, 1931)
• Aequispirella finlayi (A. W. B. Powell, 1933)
• Aequispirella iredalei (H. J. Finlay, 1924) †
• Aequispirella kaawaensis (Laws, 1940) †
• Aequispirella tenuilirata (H. J. Finlay, 1924) †
• Afrollonia vilcassina Pacaud, 2017 †
• Agagus agagus Jousseaume, 1894
• Agagus stellamaris D. G. Herbert, 1991
• Agariste compressa (Cantraine, 1835) †
• Agariste juliencilisi Landau, Marquet & Grigis, 2003 †
• Agariste phrygium (D. G. Herbert & Kilburn, 1986)
• Agathistoma antiqua S. N. Nielsen, Frassinetti & Bandel, 2004 †
• Agathistoma fasciatum (Born, 1778)
• Agathistoma hotessierianum (d'Orbigny, 1842)
• Agathistoma lividomaculatum (C. B. Adams, 1845)
• Agathistoma nordestinum Dornellas, Graboski, Hellberg & Lotufo, 2021
• Agathistoma viridulum (Gmelin, 1791)
• Agathodonta africana (Rennie, 1930) †
• Agathodonta dentigera (A. d'Orbigny, 1842) †
• Agathodonta elegans (Deshayes, 1842) † accepted as Agathodonta dentigera (A. d'Orbigny, 1842) †
• Akoya akoya (Kuroda, 1942)
• Akoya platinum (Dall, 1890)
• Akritogyra conspicua (Monterosato, 1880)
• Akritogyra curvilineata Warén, 1992
• Akritogyra helicella Warén, 1993
• Akritogyra similis (Jeffreys, 1883)
• Alaionema kyrgyzensis Gubanov, Blodgett & Lytochkin, 1995 †
• Alcyna acia Cotton, 1948
• Alcyna australis Hedley, 1907
• Alcyna exigua (A. Gould, 1861)
• Alcyna kingensis (Gabriel, 1956)
• Alcyna lifuensis Melvill & Standen, 1896
• Alcyna lucida (H. Adams, 1868)
• Alcyna ocellata A. Adams, 1860
• Alcyna subangulata Pease, 1861
• Altotomaria reticulata Ketwetsuriya, Karapunar, Charoentitirat & Nützel, 2020 †
• Altrix altior (O. Meyer & Aldrich, 1886) †
• Altrix caminata (Darragh, 1997) †
• Altrix leesi (Sohl, 1992) †
• Altrix trifolium (Dall, 1881)
• Amberleya (Eucyclus) acuminata (A. d'Orbigny, 1842) † accepted as Eucyclus acuminatus (A. d'Orbigny, 1842) †
• Amberleya (Eucyclus) chassyana (A. d'Orbigny, 1842) † accepted as Eucyclus chassyanus (A. d'Orbigny, 1842) †
• Amberleya (Eucyclus) desvoidyi (A. d'Orbigny, 1842) † accepted as Eucyclus desvoidyi (A. d'Orbigny, 1842) †
• Amberleya (Eucyclus) marollina (A. d'Orbigny, 1842) † accepted as Eucyclus marollinus (A. d'Orbigny, 1842) †
• Amberleya (Eucyclus) royana (A. d'Orbigny, 1842) † accepted as Eucyclus royanus (A. d'Orbigny, 1842) †
• Amberleya angusta Cossmann, 1885 † (uncertain > unassessed)
• Amberleya armigera Lycett, 1863 † (uncertain > unassessed)
• Amberleya bathonica L. R. Cox & Arkell, 1950 †
• Amberleya bezanconi Cossmann, 1888 † accepted as Eucyclus bezanconi (Cossmann, 1888) †
• Amberleya cretacea Beisel, 1983 †
• Amberleya torosa Marwick, 1953 †
• Amberleya zealandica Trechmann, 1923 †
• Amblychilepas acra (Cotton, 1947) †
• Amblychilepas compressa (Thiele, 1930)
• Amblychilepas crucis (C. E. Beddome, 1883)
• Amblychilepas javanicensis (Lamarck, 1822)
• Amblychilepas nigrita (G. B. Sowerby I, 1835)
• Amblychilepas oblonga (Menke, 1843)
• Amblychilepas omicron (Crosse & P. Fischer, 1864)
• Amblychilepas platyactis J. H. McLean & Kilburn, 1986
• Amonilea crescens (T. Fuchs, 1870) †
• Amonilea mitis (Deshayes, 1863) †
• Amonilea parnensis (Bayan, 1870) †