Acanthophora J.V.Lamouroux, 1813 (additional source)
Acanthophora nayadiformis (Delile) Papenfuss, 1968 (additional source)
Acetabularia parvula Solms-Laubach, 1895 accepted as Parvocaulis parvulus (Solms-Laubach) S.Berger, Fettweiss, Gleissberg, Liddle, U.Richter, Sawitzky & Zuccarello, 2003 (additional source)
Acrochaetium Nägeli, 1858 (additional source)
Acrochaetium codicola Børgesen, 1927 accepted as Colaconema codicola (Børgesen) Stegenga, J.J.Bolton & R.J.Anderson, 1997 (basis of record)
Acrochaetium crassipes (Børgesen) Børgesen, 1915 (additional source)
Acrochaetium daviesii (Dillwyn) Nägeli, 1862 accepted as Colaconema daviesii (Dillwyn) Stegenga, 1985 (additional source)
Acrochaetium liagorae Børgesen, 1915 (additional source)
Acrochaetium moniliforme (Rosenvinge) Børgesen, 1915 (additional source)
Acrochaetium savianum (Meneghini) Nägeli, 1862 accepted as Colaconema savianum (Meneghini) R.Nielsen, 1994 (additional source)
Acrochaetium secundatum (Lyngbye) Nägeli, 1858 (additional source)
Acrochaetium subseriatum Børgesen, 1932 (additional source)
Acrosorium Zanardini ex Kützing, 1869 (additional source)
Acrosorium venulosum (Zanardini) Kylin, 1924 (additional source)
Acrothamnion J.Agardh, 1892 (additional source)
Acrothamnion preissii (Sonder) E.M.Wollaston, 1968 (additional source)
Aeodes J.Agardh, 1876 (additional source)
Agardhiella F.Schmitz, 1897 (additional source)
Agardhiella subulata (C.Agardh) Kraft & M.J.Wynne, 1979 (additional source)
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 (additional source)
Aglaothamnion tripinnatum (C.Agardh) Feldmann-Mazoyer, 1941 (additional source)
Ahnfeltiopsis P.C.Silva & DeCew, 1992 (additional source)
Aiolocolax pulchellus Pocock, 1956 (additional source)
Amansia J.V.Lamouroux, 1809 (basis of record)
Amphiroa J.V.Lamouroux, 1812 (additional source)
Amphiroa beauvoisii J.V.Lamouroux, 1816 (additional source)
Amphiroa cryptarthrodia Zanardini, 1843 (additional source)
Amphiroa fragilissima (Linnaeus) J.V.Lamouroux, 1816 (additional source)
Amphiroa rigida J.V.Lamouroux, 1816 (additional source)
Anadyomene J.V.Lamouroux, 1812 (additional source)
Anadyomene stellata (Wulfen) C.Agardh, 1823 (additional source)
Anotrichium Nägeli, 1862 (additional source)
Anotrichium furcellatum (J.Agardh) Baldock, 1976 (additional source)
Anotrichium tenue (C.Agardh) Nägeli, 1862 (additional source)
Antithamnion Nägeli, 1847 (additional source)
Antithamnion diminuatum Wollaston, 1968 (additional source)
Aphanothece Nägeli, 1849 (additional source)
Aphanothece castagnei (Kützing) Rabenhorst, 1865 (additional source)
Aphanothece pallida (Kützing) Rabenhorst, 1863 (basis of record)
Aphanothece stagnina (Sprengel) A.Braun, 1863 (additional source)
Apoglossum J.Agardh, 1898 (additional source)
Apoglossum gregarium (E.Y.Dawson) M.J.Wynne, 1985 accepted as Phrix spatulata (E.Y.Dawson) M.J.Wynne, M.Kamiya & J.A.West, 2018 (additional source)
Apoglossum ruscifolium (Turner) J.Agardh, 1898 (additional source)
Arthrospira Sitzenberger ex Gomont, 1892 (additional source)
Arthrospira platensis Gomont, 1892 (basis of record)
Asparagopsis Montagne, 1840 (additional source)
Asparagopsis armata Harvey, 1855 (additional source)
Asparagopsis taxiformis (Delile) Trevisan de Saint-Léon, 1845 (additional source)
Asteronema Delépine & Asensi, 1975 (additional source)
Asteronema rhodochortonoides (Børgesen) D.G.Müller & Parodi, 1994 accepted as Asterocladon rhodochortonoides (Børgesen) S.Uwai, C.Nagasato, T.Motomura & K.Kogame, 2005 (additional source)
Bachelotia (Bornet) Kuckuck ex G.Hamel, 1939 (additional source)
Bachelotia antillarum (Grunow) Gerloff, 1959 (additional source)
Balliella H.Itono & T.Tanaka, 1973 (additional source)
Bangia Lyngbye, 1819 (additional source)
Bangia atropurpurea (Mertens ex Roth) C.Agardh, 1824 (additional source)
Beckerella Kylin, 1956 accepted as Ptilophora Kützing, 1847 (additional source)
Bifurcaria Stackhouse, 1809 (additional source)
Blennothrix Kützing ex Anagnostidis & Komárek, 1988 (basis of record)
Blennothrix lyngbyacea (Kützing ex Gomont) Anagnostidis & Komárek, 1988 (basis of record)
Blidingia Kylin, 1947 (additional source)
Blidingia marginata (J.Agardh) P.J.L.Dangeard ex Bliding, 1963 (additional source)
Blidingia minima (Nägeli ex Kützing) Kylin, 1947 (additional source)
Boodlea G.Murray & De Toni, 1889 (additional source)
Boodlea struveoides M.Howe, 1918 (additional source)
Boodleopsis A.Gepp & E.S.Gepp, 1911 (basis of record)
Boodleopsis pusilla (Collins) W.R.Taylor, A.B.Joly & Bernatowicz, 1953 (basis of record)
Bornetia Thuret, 1855 (additional source)
Bostrychia Montagne, 1842 (additional source)
Botryocladia chiajeana (Meneghini) Kylin, 1931 accepted as Irvinea chiajeana (Meneghini) Cormaci, Alongi & G.Furnari, 2012 (additional source)
Botryocladia madagascariensis G.Feldmann, 1945 (additional source)
Botryocladia pyriformis (Børgesen) Kylin, 1931 (additional source)
Brachytrichia Zanardini ex Bornet & Flahault, 1886 (basis of record)
Brachytrichia lloydii (P.L.Crouan & H.M.Crouan) P.C.Silva, 1996 (basis of record)
Brachytrichia lloydii (P.L.Crouan & H.M.Crouan) P.C.Silva, 1996 (new combination reference)
Brachytrichia quoyi Bornet & Flahault, 1886 (basis of record)
Branchioglossum Kylin, 1924 (additional source)
Bryopsis corymbosa J.Agardh, 1842 (additional source)
Bryopsis hypnoides J.V.Lamouroux, 1809 (additional source)
Bryopsis pennata J.V.Lamouroux, 1809 (additional source)
Bryopsis plumosa (Hudson) C.Agardh, 1823 (additional source)
Calliblepharis Kützing, 1843 (additional source)
Calliblepharis fimbriata (Greville) Kützing, 1843 (basis of record)
Callithamniella Feldmann-Mazoyer, 1938 (additional source)
Callithamnion Lyngbye, 1819 (additional source)
Callophyllis Kützing, 1843 (additional source)
Calothrix C.Agardh ex Bornet & Flahault, 1886 (basis of record)
Calothrix aeruginea Thuret ex Bornet & Flahault, 1886 (basis of record)
Calothrix confervicola C.Agardh ex Bornet & Flahault, 1886 (basis of record)
Calothrix contarenii Bornet & Flahault, 1886 (basis of record)
Calothrix crustacea Thuret ex Bornet & Flahault, 1886 accepted as Scytonematopsis crustacea (Thuret ex Bornet & Flahault) Koválik & Komárek, 1988 (basis of record)
Calothrix pulvinata C.Agardh ex Bornet & Flahault, 1886 (basis of record)
Calothrix scopulorum C.Agardh ex Bornet & Flahault, 1886 (additional source)
Carpomitra Kützing, 1843 (additional source)
Carradoriella P.C.Silva, 1996 (basis of record)
Catenella Greville, 1830 (additional source)
Catenella caespitosa (Withering) L.M.Irvine, 1976 (additional source)
Caulacanthus Kützing, 1843 (additional source)