• Acetabularia acetabulum (Linnaeus) P.C. Silva, 1952: turf
• Acetabularia caliculus J.V.Lamouroux, 1824: turf
• Acetabularia chiavonica Squinabol, 1902 †: turf
• Acetabularia crenulata J.V. Lamouroux, 1816: turf
• Acetabularia crenulata J.V.Lamouroux, 1816: turf
• Acetabularia dentata Solms-Laubach, 1895: turf
• Acetabularia dentata Solms-Laubach, 1895: turf
• Acetabularia farlowii Solms-Laubach, 1895: turf
• Acetabularia farlowii Solms-Laubach, 1895: turf
• Acetabularia haemmerlingii H.G.Schweiger & Berger, 1975: turf
• Acetabularia jalakanyakae Sani, Madhu, R.K.Kohli, K.Gupta & Bast, 2021: turf
• Acetabularia kilneri J.Agardh, 1887: turf
• Acetabularia major G.Martens, 1866: turf
• Acetabularia moldavica Barattolo, Ionesi & Ţibuleac, 2019 †: turf
• Acetabularia peniculus (R.Brown ex Turner) Solms-Laubach, 1895: turf
• Acetabularia ryukyuensis Okamura & Yamada, 1932: turf
• Acetabularia schenckii K. Möbius, 1889: turf
• Acetabularia schenckii Möbius, 1889: turf
• Acicularia alaica Maslov, 1956 †: turf
• Acicularia albrightii Johnson & Kaska: turf
• Acicularia americana Konishi & Epis: turf
• Acicularia andrusovii Livental, 1946 †: turf
• Acicularia antiqua Pia, 1936 †: turf
• Acicularia archiacii L.Morellet & J.Morellet, 1922 †: turf
• Acicularia azerbaidganica Livental, 1946 †: turf
• Acicularia clapei Jaffrezo: turf
• Acicularia clavata L.Morellet & J.Morellet, 1922 †: turf
• Acicularia cornigera L.Morellet & J.Morellet, 1922 †: turf
• Acicularia dubossariensis Maslov, 1961 †: turf
• Acicularia dyumatsenae Pia: turf
• Acicularia endoi Praturlon, 1964 †: turf
• Acicularia eocaenica Munier-Chalmas ex L.Morellet & J.Morellet, 1922 †: turf
• Acicularia ferganensis Maslov, 1956 †: turf
• Acicularia hebertii L.Morellet & J.Morellet, 1922 †: turf
• Acicularia indica Varma: turf
• Acicularia intermedia Dragastan, 1967 †: turf
• Acicularia jurassica J.H.Johnson: turf
• Acicularia mediopora Munier-Chalmas: turf
• Acicularia michelinii Munier-Chalmas ex L.Morellet & J.Morellet, 1922 †: turf
• Acicularia micropora Munier-Chalmas ex L.Morellet & J.Morellet, 1922 †: turf
• Acicularia munieri L.Morellet & J.Morellet, 1913 †: turf
• Acicularia parvula Munier-Chalmas ex L.Morellet & J.Morellet, 1922 †: turf
• Acicularia pavantina d'Archiac, 1846 †: turf
• Acicularia transylvana Bányai & Morellet: turf
• Acicularia valetii Segonzac, 1971 †: turf
• Acicularia weisswasserensis Schlagintweit & D.Sanders, 2010 †: turf
• Aciculella bacillum Pia, 1930 †: turf
• Aciculella ogilvie-gordoniae G.F.Elliott, 1971 †: turf
• Acroporella anceps Segonzac, 1976 †: turf
• Acroporella bacilliformis (Sokač) I.I.Bucur et al., 2012 †: turf
• Acroporella cairensis A.Mancinelli, 2006 †: turf
• Acroporella occidentalis Johnson & Kaska †: turf
• Acroporella prisca (Pia) Grgasović, 2022 †: turf
• Actinoporella cretacica Raineri, 1922 †: turf
• Actinoporella krymensis Maslov, 1958 †: turf
• Actinoporella kukociorum Radoičić, 1975 †: turf
• Actinoporella maslovii Praturlon, 1964 †: turf
• Actinoporella podolica (Alth) C.Gümbel, 1881 †: turf
• Aglaothamnion boergesenii (Aponte & D.L.Ballantine) L'Hardy-Halos & Rueness, 1997: turf
• Aglaothamnion callophyllidicola (Yamada) Boo, I.K.Lee, Rueness & Yoshida, 1991: turf
• Aglaothamnion caudatum (J.Agardh) Feldmann-Mazoyer, 1941: turf
• Aglaothamnion chadefaudii L'Hardy-Halos, 1984: turf
• Aglaothamnion chejuense G.H.Kim & I.K.Lee: turf
• Aglaothamnion circinnatum (Womersley) Cormaci, G. Furnari & Alongi, 2023: turf
• Aglaothamnion collinsii Aponte, D.L.Ballantine & J.N.Norris, 1997: turf
• Aglaothamnion confertum (Womersley) Cormaci, G. Furnari & Alongi, 2023: turf
• Aglaothamnion cordatum (Børgesen) Feldmann-Mazoyer, 1941: turf
• Aglaothamnion decompositum (J.Agardh) Halos: turf
• Aglaothamnion diaphanum L'Hardy-Halos & Maggs, 1991: turf
• Aglaothamnion endostolon Huisman, 2018: turf
• Aglaothamnion endovagum (Setchell & N.L.Gardner) I.A.Abbott, 1972: turf
• Aglaothamnion fasciculatum (Harvey) Maggs & L'Hardy-Halos, 1993: turf
• Aglaothamnion feldmanniae Halos, 1965: turf
• Aglaothamnion felipponei (Howe) Aponte, Ballantine & J.N.Norris, 1994: turf
• Aglaothamnion flexibile N.E.Aponte & D.L.Ballantine, 1995: turf
• Aglaothamnion gaillonii (P.L.Crouan & H.M.Crouan) Halos, 1965: turf
• Aglaothamnion herveyi (M.Howe) N.E.Aponte, D.L.Ballantine & J.N.Norris, 1994: turf
• Aglaothamnion monopodon Børgesen, 1945: turf
• Aglaothamnion obstipum Cowling, Kraft & J.A.West, 1998: turf
• Aglaothamnion okiense Kajimura, 1994: turf
• Aglaothamnion oosumiense Itono, 1971: turf
• Aglaothamnion propebyssoides (Womersley) Cormaci, G. Furnari & Alongi, 2023: turf
• Aglaothamnion pseudobyssoides (P.Crouan & H.Crouan) Halos, 1965: turf
• Aglaothamnion rabenhorstii (Kützing) L'Hardy-Halos: turf
• Aglaothamnion sarcodiae Børgesen, 1952: turf
• Aglaothamnion scopulorum (C.Agardh) Feldmann-Mazoyer, 1941: turf
• Aglaothamnion shepherdii (Womersley) Cormaci, G. Furnari & Alongi, 2023: turf
• Aglaothamnion tripinnatum (C.Agardh) Feldmann-Mazoyer, 1941: turf
• Aglaothamnion uruguayense (W.R.Taylor) N.E.Aponte, D.L.Ballantine & J.N.Norris, 1994: turf
• Aglaothamnion violaceum (Harvey) Cormaci, G.Furnari & Alongi, 2023: turf
• Ajakmalajsoria rotunda Korde, 1958 †: turf
• Alaria angusta Kjellman, 1889: turf
• Alaria cordata Tilden, 1898: turf
• Alaria costata Fallis: turf
• Alaria crassifolia Kjellman, 1885: turf
• Alaria crispa Kjellman, 1889: turf
• Alaria dolichorachis: turf
• Alaria elliptica Kjellman, 1883: turf
• Alaria esculenta (Linnaeus) Greville, 1830: turf
• Alaria flagellaris Strömfelt, 1886: turf