• Scytosiphon C.Agardh, 1820
• Scytosiphon arcanus M.Hoshino & Kogame, 2021
• Scytosiphon attenuatus Kjellman, 1883 accepted as Delamarea attenuata (Kjellman) Rosenvinge, 1893
• Scytosiphon bullosus Saunders, 1898 accepted as Dactylosiphon bullosus (D.A.Saunders) Santiañez, K.M.Lee, S.M.Boo & Kogame in Santiañez & al., 2018
• Scytosiphon canaliculatus (Setchell & N.L.Gardner) Kogame, 1996 accepted as Hapterophycus canaliculatus Setchell & N.L.Gardner, 1912
• Scytosiphon chordarius (Areschoug) Fries, 1845 accepted as Dictyosiphon chordaria Areschoug, 1847
• Scytosiphon clathratus (Roth) Lyngbye
• Scytosiphon clathratus var. uncinatus Lyngbye accepted as Ulva clathrata (Roth) C.Agardh, 1811
• Scytosiphon complanatus (Rosenvinge) Doty, 1947 accepted as Planosiphon complanatus (Rosenvinge) McDevit & G.W.Saunders, 2017
• Scytosiphon compressus (Linnaeus) Lyngbye, 1819 accepted as Ulva compressa Linnaeus, 1753
• Scytosiphon compressus var. confervoideus Lyngbye, 1819 accepted as Percursaria percursa (C.Agardh) Rosenvinge, 1893
• Scytosiphon compressus var. crispatus Lyngbye
• Scytosiphon compressus var. nematodes Wallroth
• Scytosiphon compressus var. trichodes Wallroth
• Scytosiphon crispus Skottsberg, 1907
• Scytosiphon dotyi M.J.Wynne, 1969
• Scytosiphon durvillei (Bory de Saint-Vincent) Trevisan, 1849 accepted as Colpomenia durvillei (Bory de Saint-Vincent) M.E.Ramírez, 1991
• Scytosiphon echinatus (Roth) Trevisan
• Scytosiphon erectus Lyngbye, 1819 accepted as Ulva flexuosa subsp. paradoxa (C.Agardh) M.J.Wynne, 2005
• Scytosiphon fascia (O.F.Müller) P.L.Crouan & H.M.Crouan, 1867 accepted as Petalonia fascia (O.F.Müller) Kuntze, 1898
• Scytosiphon filum (Linaeus) C.Agardh, 1820 accepted as Chorda filum (Linnaeus) Stackhouse, 1797
• Scytosiphon filum var. fistulosus (Hudson) C.Agardh, 1820 accepted as Asperococcus fistulosus (Hudson) W.J.Hooker, 1833
• Scytosiphon filum var. lomentarius (Lyngbye) C.Agardh, 1820 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon filum var. thrix (Stackhouse) C.Agardh, 1820
• Scytosiphon filum var. tomentosus (Lyngbye) C.Agardh, 1820 accepted as Halosiphon tomentosus (Lyngbye) Jaasund, 1957
• Scytosiphon fistulosus (Hudson) C.Agardh, 1811 accepted as Asperococcus fistulosus (Hudson) W.J.Hooker, 1833
• Scytosiphon foeniculaceus (Hudson) C.Agardh, 1811 accepted as Dictyosiphon foeniculaceus (Hudson) Greville, 1830
• Scytosiphon foeniculaceus var. intricatus (C.Agardh) Lyngbye, 1819 accepted as Dictyosiphon foeniculaceus (Hudson) Greville, 1830
• Scytosiphon foeniculaceus var. membranaceus Lyngbye, 1819 accepted as Dictyosiphon foeniculaceus (Hudson) Greville, 1830
• Scytosiphon gracilis Kogame, 1998 accepted as Planosiphon gracilis (Kogame) McDevit & G.W.Saunders, 2017
• Scytosiphon hippuroides Lyngbye, 1819 accepted as Dictyosiphon foeniculaceus (Hudson) Greville, 1830
• Scytosiphon intestinalis (Linnaeus) Lyngbye, 1819 accepted as Ulva intestinalis Linnaeus, 1753
• Scytosiphon intestinalis var. cornucopiae Lyngbye, 1819 accepted as Ulva intestinalis f. cornucopiae (Lyngbye) Sfriso & Curiel, 2007
• Scytosiphon intestinalis var. crispus (Roth) Lyngbye (uncertain)
• Scytosiphon intestinalis var. nematodes Wallroth, 1833 accepted as Ulva intestinalis Linnaeus, 1753
• Scytosiphon intestinalis var. physingodes Wallroth (uncertain)
• Scytosiphon intestinalis var. plynthodes Wallroth, 1833 accepted as Ulva linza Linnaeus, 1753
• Scytosiphon intestinalis var. trichodes Wallroth (uncertain)
• Scytosiphon juergensii C.Agardh, 1828 accepted as Enteromorpha juergensii Kützing, 1847
• Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon lomentaria f. castagneus (Carmichael) Kleen, 1874 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon lomentaria f. complanatus minor Setchell & N.L.Gardner, 1925 accepted as Scytosiphon dotyi M.J.Wynne, 1969
• Scytosiphon lomentaria f. cylindrica-major Setchell & N.L.Gardner (uncertain)
• Scytosiphon lomentaria f. cylindrica-nana Tokida, 1954 accepted as Scytosiphon dotyi M.J.Wynne, 1969
• Scytosiphon lomentaria f. fistulosus (Hudson) Foslie, 1890 accepted as Asperococcus fistulosus (Hudson) W.J.Hooker, 1833
• Scytosiphon lomentaria f. fistulosus Reinke, 1907 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon lomentaria f. tortilis Yamada, 1935 accepted as Scytosiphon dotyi M.J.Wynne, 1969
• Scytosiphon lomentaria f. typicus Setchell & N.L.Gardner, 1925 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon lomentaria var. complanatus Rosenvinge, 1893 accepted as Planosiphon complanatus (Rosenvinge) McDevit & G.W.Saunders, 2017
• Scytosiphon lomentaria var. fistulosus Kützing
• Scytosiphon lomentaria var. gracilis Kützing
• Scytosiphon lomentaria var. lomentaria (Lyngbye) Link represented as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon lomentaria var. zostericola Thuret, 1863 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon paradoxus (Roth) Hornemann, 1818 accepted as Spermatochnus paradoxus (Roth) Kützing, 1843
• Scytosiphon percursus (C.Agardh) Wallroth, 1833 accepted as Percursaria percursa (C.Agardh) Rosenvinge, 1893
• Scytosiphon prolifer Hariot, 1889 accepted as Corycus lanceolatus (Kützing) Skottsberg, 1921
• Scytosiphon promiscuus McDevit & G.W.Saunders, 2017
• Scytosiphon pusillus (Carmichael ex W.J.Hooker) Fries, 1845 accepted as Litosiphon laminariae (Lyngbye) Harvey, 1849
• Scytosiphon pygmaeus Reinke, 1888 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon ramellosus J.Agardh, 1836 accepted as Dictyosiphon foeniculaceus (Hudson) Greville, 1830
• Scytosiphon ramentaceus (Linnaeus) Lyngbye, 1819 accepted as Devaleraea ramentacea (Linnaeus) Guiry, 1982
• Scytosiphon ramulosus (J.E.Smith) S.F.Gray
• Scytosiphon rimosus (Montagne) Endlicher, 1843 accepted as Adenocystis rimosa (Montagne) Asensi, Delépine, Reviers & Rousseau, 2003
• Scytosiphon shibazakiorum M.Hoshino & Kogame, 2021
• Scytosiphon simpliccima
• Scytosiphon simpliccima var. complanatus (Rosenvinge) Cremades, 1990 accepted as Planosiphon complanatus (Rosenvinge) McDevit & G.W.Saunders, 2017
• Scytosiphon simplicissimus (Clemente) Cremades, 1990 accepted as Scytosiphon lomentaria (Lyngbye) Link, 1833
• Scytosiphon subtropicus M.Hoshino, Ats.Tanaka & Kogame, 2021
• Scytosiphon templetonii S.F.Gray
• Scytosiphon tenellus Kogame, 1998 accepted as Petalonia tenella (Kogame) Santiañez & Kogeme, 2019
• Scytosiphon tomentosus (Hudson) J.Agardh, 1848 accepted as Spongonema tomentosum (Hudson) Kützing, 1849
• Scytosiphon tomentosus Hornemann, 1818 accepted as Dictyosiphon foeniculaceus (Hudson) Greville, 1830
• Scytosiphon tortilis (Suhr) Trevisan, 1849 accepted as Asperococcus tortilis Suhr, 1836
• Scytosiphon tortilis Ruprecht, 1850 accepted as Stictyosiphon tortilis (Gobi) Areschoug ex Reinke, 1889
• Scytosiphon tosaensis M.Hoshino & Kogame, 2021
• Scytosiphon utricularis (Bory) Trevisan, 1849 accepted as Adenocystis utricularis (Bory) Skottsberg, 1907
• Scytosiphon velutinus Lyngbye, 1819 accepted as Prasiola velutina (Lyngbye) Trevisan, 1845
• Scytosiphonaceae Farlow, 1881
• Scytosiphoneae W.J.E.Santiañez, 2018