Acrochaetium Nägeli, 1858 (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)
Acrosorium Zanardini ex Kützing, 1869 (additional source)
Acrosorium venulosum (Zanardini) Kylin, 1924 (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)
Amphiroa J.V.Lamouroux, 1812 (additional source)
Amphiroa cryptarthrodia Zanardini, 1843 (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)
Antithamnion Nägeli, 1847 (additional source)
Apoglossum J.Agardh, 1898 (additional source)
Apoglossum ruscifolium (Turner) J.Agardh, 1898 (additional source)
Asparagopsis Montagne, 1840 (additional source)
Asparagopsis armata Harvey, 1855 (additional source)
Asparagopsis taxiformis (Delile) Trevisan de Saint-Léon, 1845 (additional source)
Bachelotia (Bornet) Kuckuck ex G.Hamel, 1939 (additional source)
Bachelotia antillarum (Grunow) Gerloff, 1959 (additional source)
Bangia Lyngbye, 1819 (additional source)
Bangia atropurpurea (Mertens ex Roth) C.Agardh, 1824 (additional source)
Bifurcaria Stackhouse, 1809 (additional source)
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)
Bornetia Thuret, 1855 (additional source)
Bostrychia Montagne, 1842 (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)
Callithamnion Lyngbye, 1819 (additional source)
Callophyllis Kützing, 1843 (additional source)
Calothrix C.Agardh ex Bornet & Flahault, 1886 (basis of record)
Calothrix confervicola C.Agardh ex Bornet & Flahault, 1886 (basis of record)
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)
Caulacanthus ustulatus (Turner) Kützing, 1843 (additional source)
Caulerpa J.V.Lamouroux, 1809 (additional source)
Caulerpa racemosa (Forsskål) J.Agardh, 1873 (additional source)
Caulerpa taxifolia (M.Vahl) C.Agardh, 1817 (additional source)
Ceramium Roth, 1797 (additional source)
Ceramium callipterum Mazoyer, 1938 (additional source)
Ceramium cimbricum H.E.Petersen, 1924 (additional source)
Ceramium codii (H.Richards) Mazoyer, 1938 accepted as Stirkia codii (H.Richards) Barros-Barreto & Maggs, 2023 (additional source)
Ceramium deslongchampsii Chauvin ex Duby, 1830 (additional source)
Ceramium diaphanum (Lightfoot) Roth, 1806 (additional source)
Ceramium flaccidum (Harvey ex Kützing) Ardissone, 1871 accepted as Gayliella flaccida (Harvey ex Kützing) T.O.Cho & L.J.McIvor, 2008 (additional source)
Ceramium tenerrimum (G.Martens) Okamura, 1921 accepted as Pseudoceramium tenerrimum (G.Martens) Barros-Barreto & Maggs, 2023 (additional source)
Chaetomorpha Kützing, 1845 (additional source)
Chaetomorpha aerea (Dillwyn) Kützing, 1849 (additional source)
Chaetomorpha crassa (C.Agardh) Kützing, 1845 (additional source)
Chaetomorpha linum (O.F.Müller) Kützing, 1845 (additional source)
Champia Desvaux, 1809 (additional source)
Champia parvula (C.Agardh) Harvey, 1853 (additional source)
Chondracanthus Kützing, 1843 (additional source)
Chondracanthus acicularis (Roth) Fredericq, 1993 (additional source)
Chondracanthus teedei (Mertens ex Roth) Kützing, 1843 (additional source)
Chondria C.Agardh, 1817 (additional source)
Chondria capillaris (Hudson) M.J.Wynne, 1991 (additional source)
Chondria dasyphylla (Woodward) C.Agardh, 1817 (additional source)
Choreonema F.Schmitz, 1889 (additional source)
Choreonema thuretii (Bornet) F.Schmitz, 1889 (additional source)
Chroodactylon Hansgirg, 1885 (additional source)
Chroodactylon ornatum (C.Agardh) Basson, 1979 (additional source)
Chrysymenia J.Agardh, 1842 (additional source)
Chylocladia Greville, 1833 (additional source)
Cladophora Kützing, 1843 (additional source)
Cladophora albida (Nees) Kutzing, 1843 (additional source)
Cladophora coelothrix Kützing, 1843 (additional source)
Cladophora hutchinsiae (Dillwyn) Kützing, 1845 (additional source)
Cladophora laetevirens (Dillwyn) Kützing, 1843 (additional source)
Cladophora lehmanniana (Lindenberg) Kützing, 1843 (additional source)
Cladophora pellucida (Hudson) Kützing, 1843 accepted as Lychaete pellucida (Hudson) M.J.Wynne, 2017 (additional source)
Cladophora prolifera (Roth) Kützing, 1843 (additional source)
Cladophora sericea (Hudson) Kützing, 1843 (additional source)
Cladophora vagabunda (Linnaeus) Hoek, 1963 (additional source)
Cladosiphon Kützing, 1843 (additional source)
Codium Stackhouse, 1797 (additional source)
Codium decorticatum (Woodward) M.A.Howe, 1911 (additional source)
Codium tomentosum Stackhouse, 1797 (additional source)
Colpomenia (Endlicher) Derbès & Solier, 1851 (additional source)
Colpomenia sinuosa (Mertens ex Roth) Derbès & Solier, 1851 (additional source)
Corallina Linnaeus, 1758 (additional source)
Corallina officinalis Linnaeus, 1758 (additional source)
Crouania J.Agardh, 1842 (additional source)