Acanthophora muscoides (Linnaeus) Bory de Saint-Vincent, 1828 (additional source)
Acetabularia subg. Acicularia caliculus J.V. Lamouroux, 1824 represented as Acetabularia caliculus J.V.Lamouroux, 1824 (additional source)
Acinetospora crinita (Carmichael) Sauvageau, 1899 (additional source)
Acrochaete flustrae (Reinke) O'Kelly, 2006 accepted as Epicladia flustrae Reinke, 1889 (additional source)
Acrochaetium hallandicum (Kylin) Hamel, 1927 accepted as Colaconema hallandicum (Kylin) Afonso-Carillo, Sanson, Sangil & Diaz-Villa, 2007 (additional source)
Acrochaetium leptonema (Rosenvinge) Børgesen, 1915 accepted as Colaconema leptonema (Rosenvinge) Alongi, Cormaci & G.Furnari, 2017 (additional source)
Acrochaetium microscopicum (Nägeli ex Kützing) Nägeli, 1858 (additional source)
Acrochaetium pulchellum Børgesen, 1915 (additional source)
Acrochaetium robustum Børgesen, 1915 accepted as Colaconema robustum (Børgesen) Huisman & Woelkerling, 2018 (additional source)
Acrochaetium savianum (Meneghini) Nägeli, 1862 accepted as Colaconema savianum (Meneghini) R.Nielsen, 1994 (additional source)
Acrochaetium secundatum (Lyngbye) Nägeli, 1858 (additional source)
Agardhiella subulata (C.Agardh) Kraft & M.J.Wynne, 1979 (additional source)
Agardhinula browneae (J.Agardh) De Toni, 1897 (additional source)
Aglaothamnion cordatum (Børgesen) Feldmann-Mazoyer, 1941 (additional source)
Aglaothamnion halliae (Collins) Aponte, D.L.Ballantine & J.N.Norris, 1997 (additional source)
Aglaothamnion roseum (Roth) Maggs & L'Hardy-Halos, 1993 accepted as Gaillona rosea (Roth) Athanasiadis, 2016 (additional source)
Amphiroa beauvoisii J.V.Lamouroux, 1816 (additional source)
Amphiroa fragilissima (Linnaeus) J.V.Lamouroux, 1816 (additional source)
Amphiroa rigida J.V.Lamouroux, 1816 (additional source)
Anadyomene saldanhae A.B.Joly & E.C.Oliveira, 1969 (additional source)
Anadyomene stellata (Wulfen) C.Agardh, 1823 (additional source)
Anotrichium barbatum (C.Agardh) Nägeli, 1862 (additional source)
Anotrichium tenue (C.Agardh) Nägeli, 1862 (additional source)
Antithamnion cruciatum (C.Agardh) Nägeli, 1847 (additional source)
Antithamnion subg. Antithamnion antillanum Børgesen, 1917 represented as Antithamnion antillanum Børgesen, 1917 (additional source)
Apoglossum ruscifolium (Turner) J.Agardh, 1898 (additional source)
Asparagopsis taxiformis (Delile) Trevisan de Saint-Léon, 1845 (additional source)
Asperococcus fistulosus (Hudson) W.J.Hooker, 1833 (additional source)
Asteromenia peltata (W.R.Taylor) Huisman & A.J.K.Millar, 1996 (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 antillarum (Grunow) Gerloff, 1959 (additional source)
Bangia fuscopurpurea (Dillwyn) Lyngbye, 1819 (additional source)
Batophora occidentalis (Harvey) S.Berger & Kaever ex M.J.Wynne, 1998 (additional source)
Batophora oerstedii J.Agardh, 1854 (additional source)
Blastophysa rhizopus Reinke, 1889 (additional source)
Blidingia marginata (J.Agardh) P.J.L.Dangeard ex Bliding, 1963 (additional source)
Blidingia minima (Nägeli ex Kützing) Kylin, 1947 (additional source)
Boodleopsis pusilla (Collins) W.R.Taylor, A.B.Joly & Bernatowicz, 1953 (additional source)
Botryocladia occidentalis (Børgesen) Kylin, 1931 (additional source)
Botryocladia pyriformis (Børgesen) Kylin, 1931 (additional source)
Bryobesia johannae Weber Bosse, 1913 (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)
Callithamniella tingitana (Schousboe ex Bornet) Feldmann-Mazoyer, 1938 (additional source)
Callithamnion corymbosum (Smith) Lyngbye, 1819 (additional source)
Catenella caespitosa (Withering) L.M.Irvine, 1976 (additional source)
Caulerpa cupressoides (Vahl) C.Agardh, 1817 (additional source)
Caulerpa mexicana Sonder ex Kützing, 1849 (additional source)
Caulerpa ollivieri Dostál, 1929 (additional source)
Caulerpa prolifera (Forsskål) J.V.Lamouroux, 1809 (additional source)
Caulerpa racemosa (Forsskål) J.Agardh, 1873 (additional source)
Caulerpa sertularioides (S.G.Gmelin) M.Howe, 1905 (additional source)
Caulerpa taxifolia (M.Vahl) C.Agardh, 1817 (additional source)
Caulerpa webbiana Montagne, 1837 (additional source)
Ceramium brevizonatum H.E.Petersen, 1918 (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 virgatum J.D.Hooker & Harvey, 1848 (additional source)
Chaetomorpha aerea (Dillwyn) Kützing, 1849 (additional source)
Chaetomorpha antennina (Bory) Kützing, 1847 (additional source)
Chaetomorpha crassa (C.Agardh) Kützing, 1845 (additional source)
Chaetomorpha gracilis Kützing, 1845 (additional source)
Chaetomorpha linum (O.F.Müller) Kützing, 1845 (additional source)
Champia parvula (C.Agardh) Harvey, 1853 (additional source)
Champia salicornioides Harvey, 1853 (additional source)
Chondracanthus acicularis (Roth) Fredericq, 1993 (additional source)
Chondria capillaris (Hudson) M.J.Wynne, 1991 (additional source)
Chondria collinsiana M.A.Howe, 1920 (additional source)
Chondria curvilineata F.S.Collins & Hervey, 1917 (additional source)
Chondria dasyphylla (Woodward) C.Agardh, 1817 (additional source)
Chondria polyrhiza F.S.Collins & Hervey, 1917 (additional source)
Chondrophycus corallopsis (Montagne) K.W.Nam, 1999 accepted as Palisada corallopsis (Montagne) Sentíes, Fujii & Díaz-Larrea, 2008 (additional source)
Chondrophycus papillosus (C.Agardh) D.J.Garbary & J.T.Harper, 1998 accepted as Palisada perforata (Bory) K.W.Nam, 2007 (additional source)
Chondrophycus poiteaui (J.V.Lamouroux) K.W.Nam, 1999 accepted as Yuzurua poiteaui (J.V.Lamouroux) Martin-Lescanne, 2010 (additional source)
Chroodactylon ornatum (C.Agardh) Basson, 1979 (additional source)
Chrysymenia enteromorpha Harvey, 1853 accepted as Botryocladia enteromorpha (Harvey) W.E.Schmidt, Lozada-Troche, D.L.Ballantine & Fredericq, 2017 (additional source)
Chrysymenia halymenioides Harvey, 1853 (additional source)
Chrysymenia ventricosa (J.V.Lamouroux) J.Agardh, 1842 (additional source)
Cladophora albida (Nees) Kutzing, 1843 (additional source)
Cladophora catenata (Linnaeus) Kützing, 1843 accepted as Cladophora catenata Kützing, 1843 (additional source)
Cladophora coelothrix Kützing, 1843 (additional source)
Cladophora conferta P.Crouan & H.Crouan, 1865 (additional source)
Cladophora crystallina (Roth) Kützing, 1843 (additional source)
Cladophora dalmatica Kützing, 1843 (additional source)
Cladophora flexuosa (O.F.Müller) Kützing, 1843 (additional source)
Cladophora glomerata (Linnaeus) Kützing, 1843 (additional source)
Cladophora hutchinsiae (Dillwyn) Kützing, 1845 (additional source)
Cladophora laetevirens (Dillwyn) Kützing, 1843 (additional source)
Cladophora liebetruthii Grunow, 1884 (additional source)
Cladophora liniformis Kützing, 1849 (additional source)
Cladophora prolifera (Roth) Kützing, 1843 (additional source)
Cladophora ruchingeri (C.Agardh) Kützing, 1845 (additional source)
Cladophora sericea (Hudson) Kützing, 1843 (additional source)
Cladophora socialis Kützing, 1849 (additional source)
Cladophora vagabunda (Linnaeus) Hoek, 1963 (additional source)
Cladophoropsis macromeres W.R.Taylor, 1928 (additional source)