• Abditodentrix pseudothalmanni (Boltovskoy & Guissani de Kahn, 1981): Pliocene
• Acanthinula clairi Schlickum & Truc, 1972 †: Piacenzian
• Acanthocardia bianconiana (Cocconi, 1873) †: Pliocene
• Acanthocardia perrugosa (Fontannes, 1882) †: Pliocene
• Acanthochitona flebilis (Laws, 1950) †: Pliocene
• Acanthotrophon striatus (Gabb, 1873) †: Pliocene
• Acar opuraensis (Bartrum & A. W. B. Powell, 1928) †: Pliocene
• Acar powelli Laws, 1950 †: Pliocene
• Acasta muricata Seguenza, 1876 †: Pliocene
• Acasta spongites (Poli, 1791): Pliocene
• Acasta undulata Darwin, 1854 †: Pliocene
• Acesta imitata (Suter, 1917) †: Pliocene
• Acesta plioiberica Brunetti & Della Bella, 2024 †: Piacenzian
• Acharax burica (Olsson, 1942) †: Pliocene
• Acicula kadolskyi Manganelli, Cianfanelli, Barbato & Benocci, 2014 †: Zanclean
• Acirsa cookiana (Dell, 1956): Pliocene
• Aclis aurisparva Bertolaso & Garilli, 2009 †: Pliocene
• Aclis bartolomeae Tabanelli, 1997 †: Piacenzian
• Aclis cellinii Chirli, 2009 †: Piacenzian
• Aclis minor (T. Brown, 1827): Piacenzian
• Aclis planostoma (F. W. Hutton, 1885) †: Pliocene
• Aclis scalaris G. Seguenza, 1876 †: Piacenzian
• Aclis talaverai Brunetti & Cresti, 2018: Piacenzian
• Acremodontina varicosa B. A. Marshall, 1995: Pliocene
• Acrilloscala geniculata (Brocchi, 1814) †: Pliocene
• Acrosterigma praecygnorum (Ludbrook, 1955) †: Pliocene
• Acteocina lajonkaireana (Basterot, 1825) †: Zanclean
• Acteocina puruha Pilsbry & Olsson, 1941 †: Pliocene
• Acteon semistriatus (Basterot, 1825) †: Zanclean
• Actinobalanus actinomorphus (Moroni, 1952) †: Pliocene
• Actinobalanus bisculcatus (Darwin, 1854): Pliocene
• Actinobalanus dolosus (Darwin, 1854) †: Pliocene
• Actinobalanus inclusus (Darwin, 1854): Pliocene
• Actinobalanus stellaris (Brocchi, 1814) †: Pliocene
• Acuticosta prolonga Zykin, 1980 †: Piacenzian
• Adamussium necopinatum Quilty, Darragh, Gallagher & Harding, 2016 †: Pliocene
• Adelphotectonica bieleri Ceulemans, Van Dingenen & Landau, 2018 †: Zanclean
• Ademitrella insolentior Ludbrook, 1941 †: Pliocene
• Admetula serrata (Bronn, 1831) †: Zanclean
• Aegopinella boeckeli Schlickum, 1977 †: Piacenzian
• Aegopinella lozeki Schlickum, 1975 †: Piacenzian
• Aegopinella reyi Schlickum, 1975 †: Piacenzian
• Aeneator problematicus C. A. Fleming, 1943 †: Pliocene
• Aenigmapyrgus altaicus Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus hydrobioides Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus martinsoni Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus mediocinctus Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus pulcher Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus steklovi Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus subangulatus Popova & Starobogatov, 1970 †: Pliocene
• Aenigmapyrgus subcarinatus Popova & Starobogatov, 1970 †: Pliocene
• Aequiyoldia defossata Quilty, Darragh, Gallagher & Harding, 2016 †: Pliocene
• Afrocardium hirsutum (Bronn, 1831) †: Pliocene
• Agariste juliencilisi Landau, Marquet & Grigis, 2003 †: Zanclean
• Agassizia aequipetala Gregory, 1892 †: Pliocene
• Agatha pittensis (Marwick, 1928) †: Pliocene
• Agladrillia callothyra Woodring, 1928 †: Pliocene
• Akardita iberica La Perna, Brunetti & Della Bella, 2018 †: Zanclean
• Akardita subrevoluta (De Stefani, 1888) †: Zanclean
• Akatopora circumsaepta (Uttley, 1951): Pliocene
• Akatopora leucocypha (Marcus, 1937): Pliocene
• Akatopora tincta (Hastings, 1930): Pliocene
• Akleistostoma walleri Petuch, Berschauer & R. F. Myers, 2018 †: Piacenzian
• Alabamina tenuimarginata (Chapman, Parr & Collins, 1934) †: Zanclean
• Alabaminella weddellensis (Earland, 1936): Pliocene
• Alcithoe arabicula Marwick, 1926 †: Pliocene
• Alcithoe bartrumi (L. C. King, 1933) †: Pliocene
• Alcithoe brevis Marwick, 1926 †: Pliocene
• Alcithoe bulbus (Marwick, 1931) †: Pliocene
• Alcithoe concisa Marwick, 1931 †: Pliocene
• Alcithoe gatesi Marwick, 1926 †: Pliocene
• Alcithoe haweraensis Marwick, 1926 †: Pliocene
• Alcithoe parva Marwick, 1926 †: Pliocene
• Alcithoe powelli (Laws, 1936) †: Pliocene
• Alcithoe renwicki (Marwick, 1928) †: Pliocene
• Alcithoe whakinoensis Marwick, 1926 †: Pliocene
• Alcithoe wilsonae (A. W. B. Powell, 1933): Pliocene
• Alderina cesticella Canu & Bassler, 1923 †: Zanclean
• Alderina hanzawai Kataoka, 1957 †: Pliocene
• Alderina nodulosa (Uttley, 1949) †: Pliocene
• Alderina pedunculata (Manzoni, 1870) †: Pliocene
• Alderina pyriformis Canu & Bassler, 1928 †: Pliocene
• Alderina smitti Osburn, 1950: Pliocene
• Aliger galliformis (Pilsbry & C. W. Johnson, 1917) †: Pliocene
• Allantopora dentata (Wood, 1844) †: Pliocene
• Allocentrotus japonicus Nisiyama, 1966 †: Zanclean
• Alocospira paeroa (C. A. Fleming, 1943) †: Pliocene
• Alocospira subhebera (Marwick, 1926) †: Pliocene
• Alucinoma persquamulosa (Sacco, 1901) †: Piacenzian
• Alvania absuturalis Chirli & Forli, 2021 †: Pliocene
• Alvania belli Harmer, 1920 †: Pliocene
• Alvania bicingulata (G. Seguenza, 1876) †: Pliocene
• Alvania calasi Van Dingenen, Ceulemans & Landau, 2016 †: Zanclean
• Alvania caporalii Chirli, 2006 †: Pliocene
• Alvania cathyae Landau, Marquet & Grigis, 2004 †: Pliocene
• Alvania cerreti Gardella, Bertaccini, Bertamini, Bongiardino, Petracci & Tabanelli, 2021 †: Zanclean
• Alvania cioppii Chirli, 2006 †: Pliocene
• Alvania cossmanni Harmer, 1920 †: Pliocene
• Alvania densecostata Harmer, 1920 †: Pliocene
• Alvania dimitrii Garilli & Parrinello, 2010 †: Piacenzian