Acanthophora J.V.Lamouroux, 1813 (additional source)
Acanthophora delilei J.V.Lamouroux, 1813 accepted as Acanthophora nayadiformis (Delile) Papenfuss, 1968 (additional source)
Acanthophora dendroides Harvey, 1855 (additional source)
Acanthophora muscoides (Linnaeus) Bory de Saint-Vincent, 1828 (basis of record)
Acanthophora muscoides (Linnaeus) Bory de Saint-Vincent, 1828 (additional source)
Acanthophora nayadiformis (Delile) Papenfuss, 1968 (basis of record)
Acanthophora spicifera (M.Vahl) Børgesen, 1910 (additional source)
Acetabularia J.V.Lamouroux, 1812 (additional source)
Acetabularia acetabulum (Linnaeus) P.C.Silva, 1952 (basis of record)
Acetabularia calyculus J.V.Lamouroux, 1824 (basis of record)
Acetabularia clavata Yamada, 1934 accepted as Parvocaulis clavatus (Yamada) S.Berger, U.Fettweiss, S.Gleissberg, L.B.Liddle, U.Richter, H.Sawitzky & G.C.Zuccarello, 2003 (additional source)
Acetabularia exigua Solms-Laubach, 1895 accepted as Parvocaulis polyphysoides (P.Crouan & H.Crouan) S.Berger, U.Fettweiss, S.Gleissberg, L.B.Liddle, U.Richter, H.Sawitzky & G.C.Zuccarello, 2003 (additional source)
Acetabularia moebii Solms-Laubach, 1895 accepted as Parvocaulis parvulus (Solms-Laubach) S.Berger, Fettweiss, Gleissberg, Liddle, U.Richter, Sawitzky & Zuccarello, 2003 (basis of record)
Acetabularia parvula Solms-Laubach, 1895 accepted as Parvocaulis parvulus (Solms-Laubach) S.Berger, Fettweiss, Gleissberg, Liddle, U.Richter, Sawitzky & Zuccarello, 2003 (additional source)
Acetabularia pusilla (M.Howe) Collins, 1909 accepted as Parvocaulis pusillus (M.Howe) S.Berger, U.Fettweiss, S.Gleissberg, L.B.Liddle, U.Richter, H.Sawitzky & G.C.Zuccarello, 2003 (basis of record)
Acetabularia pusilla (M.Howe) Collins, 1909 accepted as Parvocaulis pusillus (M.Howe) S.Berger, U.Fettweiss, S.Gleissberg, L.B.Liddle, U.Richter, H.Sawitzky & G.C.Zuccarello, 2003 (additional source)
Acetabularia subg. Acetabularia (basis of record)
Acetabularia subg. Acicularia (basis of record)
Acinetospora Bornet, 1891 (additional source)
Acinetospora crinita (Carmichael) Sauvageau, 1899 (additional source)
Acinetosporaceae Hamel ex J. Feldmann, 1937 (basis of record)
Acrochaete N.Pringsheim, 1862 accepted as Ulvella P.L.Crouan & H.M.Crouan, 1859 (additional source)
Acrochaete viridis (Reinke) R.Nielsen, 1979 accepted as Ulvella viridis (Reinke) R.Nielsen, C.J.O'Kelly & B.Wysor, 2013 (additional source)
Acrochaetium Nägeli, 1858 (additional source)
Acrochaetium candelabrum Børgesen, 1942 (additional source)
Acrochaetium chnoosporae Børgesen, 1942 accepted as Audouinella chnoosporae (Børgesen) Garbary, 1987 (additional source)
Acrochaetium codicola Børgesen, 1927 accepted as Colaconema codicola (Børgesen) Stegenga, J.J.Bolton & R.J.Anderson, 1997 (basis of record)
Acrochaetium codicola Børgesen, 1927 accepted as Colaconema codicola (Børgesen) Stegenga, J.J.Bolton & R.J.Anderson, 1997 (additional source)
Acrochaetium crassipes (Børgesen) Børgesen, 1915 (basis of record)
Acrochaetium crassipes (Børgesen) Børgesen, 1915 (additional source)
Acrochaetium daviesii (Dillwyn) Nägeli, 1862 accepted as Colaconema daviesii (Dillwyn) Stegenga, 1985 (source of synonymy)
Acrochaetium endozoicum (Darbishire) Batters, 1902 (additional source)
Acrochaetium gracile Børgesen, 1915 accepted as Colaconema gracile (Børgesen) Ateweberhan & Prud'homme van Reine, 2005 (additional source)
Acrochaetium hlulekaense Stegenga, 1985 (basis of record)
Acrochaetium hypneae (Børgesen) Børgesen, 1915 accepted as Colaconema hypneae (Børgesen) A.A.Santos & C.W.N.Moura, 2010 (basis of record)
Acrochaetium liagorae Børgesen, 1915 (additional source)
Acrochaetium mauritianum Børgesen, 1942 (additional source)
Acrochaetium microscopicum (Nägeli ex Kützing) Nägeli, 1858 (additional source)
Acrochaetium moniliforme (Rosenvinge) Børgesen, 1915 (additional source)
Acrochaetium savianum (Meneghini) Nägeli, 1862 accepted as Colaconema savianum (Meneghini) R.Nielsen, 1994 (basis of record)
Acrochaetium savianum (Meneghini) Nägeli, 1862 accepted as Colaconema savianum (Meneghini) R.Nielsen, 1994 (additional source)
Acrochaetium secundatum (Lyngbye) Nägeli, 1858 (additional source)
Acrochaetium seriatum Børgesen, 1915 accepted as Colaconema hypneae (Børgesen) A.A.Santos & C.W.N.Moura, 2010 (additional source)
Acrochaetium spongicola Weber Bosse, 1921 (basis of record)
Acrochaetium spongicola Weber Bosse, 1921 (additional source)
Acrochaetium subseriatum Børgesen, 1932 (additional source)
Acrochaetium trichogloeae Børgesen, 1952 (basis of record)
Acrocladus Nägeli, 1847 accepted as Lychaete J.Agardh, 1846 (basis of record)
Acrocladus herpesticus (Montagne) Boedeker, 2016 accepted as Lychaete herpestica (Montagne) M.J.Wynne, 2017 (basis of record)
Acrocystis Zanardini, 1872 (additional source)
Acrocystis nana Zanardini, 1872 (additional source)
Acrosorium Zanardini ex Kützing, 1869 (additional source)
Acrosorium acrospermum (J.Agardh) Kylin, 1938 (additional source)
Acrosorium amphiroae Jaasund, 1976 (additional source)
Acrosorium ciliolatum (Harvey) Kylin, 1924 (basis of record)
Acrosorium cincinnatum M.J.Wynne, 1986 (basis of record)
Acrosorium deformatum (Suhr) Papenfuss, 1943 (additional source)
Acrosorium maculatum (Sonder ex Kützing) Papenfuss, 1940 (additional source)
Acrosorium reptans (P.Crouan & H.Crouan) Kylin, 1924 accepted as Cryptopleura ramosa (Hudson) L.Newton, 1931 (basis of record)
Acrosorium reptans (P.Crouan & H.Crouan) Kylin, 1924 accepted as Cryptopleura ramosa (Hudson) L.Newton, 1931 (source of synonymy)
Acrosorium uncinatum (Turner) Kylin, 1924 accepted as Cryptopleura ramosa (Hudson) L.Newton, 1931 (source of synonymy)
Acrosorium venulosum (Zanardini) Kylin, 1924 (basis of record)
Acrosorium venulosum (Zanardini) Kylin, 1924 (additional source)
Acrothamnion J.Agardh, 1892 (additional source)
Acrothamnion preissii (Sonder) E.M.Wollaston, 1968 (basis of record)
Acrotylus J.Agardh, 1849 (additional source)
Acrotylus australis J.Agardh, 1849 (additional source)
Actinomonadaceae Kent, 1881 (basis of record)
Actinotrichia Decaisne, 1842 (additional source)
Actinotrichia fragilis (Forsskål) Børgesen, 1932 (additional source)
Aeodes J.Agardh, 1876 (additional source)
Aeodes digitata F.Schmitz, 1921 (basis of record)
Aeodes digitata F.Schmitz, 1921 (additional source)
Aeodes orbitosa (Suhr) F.Schmitz, 1894 accepted as Pachymenia orbitosa (Suhr) L.K.Russell, 2009 (additional source)
Aeodes ulvoidea F.Schmitz, 1894 accepted as Pachymenia ulvoidea (F.Schmitz) L.K.Russell, 2010 (additional source)
Aerosakkonemataceae Strunecky & Mares, 2023 (basis of record)
Agardhiella F.Schmitz, 1897 (additional source)
Agardhiella subulata (C.Agardh) Kraft & M.J.Wynne, 1979 (basis of record)
Aglaothamnion Feldmann-Mazoyer, 1941 (additional source)
Aglaothamnion byssoides (Arnott ex Harvey) C.F.Boudouresque & M.M.Perret-Boudouresque, 1987 accepted as Aglaothamnion tenuissimum (Bonnemaison) Feldmann-Mazoyer, 1941 (additional source)
Aglaothamnion cordatum (Børgesen) Feldmann-Mazoyer, 1941 (additional source)
Aglaothamnion hookeri (Dillwyn) Maggs & Hommersand, 1993 accepted as Gaillona hookeri (Dillwyn) Athanasiadis, 2016 (basis of record)
Aglaothamnion hookeri (Dillwyn) Maggs & Hommersand, 1993 accepted as Gaillona hookeri (Dillwyn) Athanasiadis, 2016 (additional source)
Aglaothamnion monopodon Børgesen, 1945 (additional source)
Aglaothamnion sarcodiae Børgesen, 1952 (additional source)
Aglaothamnion tenuissimum (Bonnemaison) Feldmann-Mazoyer, 1941 (additional source)
Aglaothamnion tripinnatum (C.Agardh) Feldmann-Mazoyer, 1941 (additional source)
Aglaozonia Zanardini, 1843 accepted as Cutleria Greville, 1830 (basis of record)
Aglaozonia Zanardini, 1843 accepted as Cutleria Greville, 1830 (source of synonymy)
Ahnfeltiopsis P.C.Silva & DeCew, 1992 (additional source)
Ahnfeltiopsis chnoosporoides (T.Tanaka & Pham-Hoàng Hô) Masuda, 1993 (additional source)
Ahnfeltiopsis complicata (Kützing) P.C.Silva & DeCew, 1992 (additional source)
Ahnfeltiopsis devoniensis (Greville) P.C.Silva & DeCew, 1992 (additional source)
Ahnfeltiopsis furcellata (C.Agardh) P.C.Silva & DeCew, 1992 accepted as Asterfilopsis furcellata (C.Agardh) M.S.Calderon & S.M.Boo, 2016 (basis of record)
Ahnfeltiopsis furcellata (C.Agardh) P.C.Silva & DeCew, 1992 accepted as Asterfilopsis furcellata (C.Agardh) M.S.Calderon & S.M.Boo, 2016 (additional source)
Ahnfeltiopsis glomerata (J.Agardh) P.C.Silva & DeCew, 1992 (additional source)
Ahnfeltiopsis polyclada (Kützing) P.C.Silva & DeCew, 1992 (additional source)
Ahnfeltiopsis vermicularis (C.Agardh) P.C.Silva & DeCew, 1992 (additional source)
Aiolocolax M.A.Pocock, 1956 (additional source)
Aiolocolax pulchellus Pocock, 1956 (basis of record)

English ant-like flower beetles for Anthicidae Latreille, 1819
English black siphon weed [from synonym] for Polysiphonia fucoides (Hudson) Greville, 1824
English bushy berry wrack [from synonym] for Cystoseira baccata (S.G.Gmelin, 1768) P.C.Silva, 1952
Swedish fjäderslick [from synonym] for Polysiphonia fucoides (Hudson) Greville, 1824