• Fucus Linnaeus, 1753
• Fucus abies-marinus S.G. Gmelin, 1768 accepted as Cystoseira abies-marina (S.G. Gmelin) C. Agardh, 1820
• Fucus abnormis Stackhouse
• Fucus abrotanifolius Linnaeus, 1753 accepted as Cystoseira foeniculacea (Linnaeus) Greville, 1830
• Fucus abrotanoides S.G. Gmelin, 1768 accepted as Cystoseira baccata (S.G. Gmelin) P.C. Silva, 1952
• Fucus abscissus Turner, 1819 accepted as Melanthalia abscissa (Turner) J.D. Hooker & Harvey, 1845
• Fucus acanthophorus J.V. Lamouroux, 1805 accepted as Acanthophora spicifera (M. Vahl) Børgesen, 1910
• Fucus acerosus Forsskål, 1775 accepted as Gelidiella acerosa (Forsskål) Feldmann & G. Hamel, 1934
• Fucus acetabulus Gouan, 1815 accepted as Kallymenia reniformis (Turner) J.G. Agardh, 1842
• Fucus acicularis Esper, 1800
• Fucus acicularis Wulfen, 1803 accepted as Chondracanthus acicularis (Roth) Fredericq, 1993
• Fucus acinaria S.G. Gmelin, 1768 accepted as Sargassum acinarium (Linnaeus) Setchell, 1933
• Fucus acinarius Linnaeus, 1753 accepted as Sargassum acinarium (Linnaeus) Setchell, 1933
• Fucus aculeatus Esper, 1798
• Fucus aculeatus Linnaeus, 1763 accepted as Desmarestia aculeata (Linnaeus) J.V. Lamouroux, 1813
• Fucus acutus Turner
• Fucus aeruginosus Turner, 1811 accepted as Gracilaria foliifera (Forsskål) Børgesen, 1932
• Fucus agarum S.G. Gmelin, 1768 accepted as Agarum clathratum Dumortier, 1822
• Fucus alatus Hudson, 1762 accepted as Membranoptera alata (Hudson) Stackhouse, 1809
• Fucus albidus Esper, 1800
• Fucus albus Esper, 1798
• Fucus albus Hudson, 1762 accepted as Ahnfeltia plicata (Hudson) E.M. Fries, 1836
• Fucus allantoides Brown ex Turner
• Fucus alveatus Turner, 1819 accepted as Gigartina alveata (Turner) J.G. Agardh, 1851
• Fucus alveolatus Esper, 1799 accepted as Mastocarpus stellatus (Stackhouse) Guiry, 1984
• Fucus amansii J.V. Lamouroux, 1805 accepted as Gelidium amansii (J.V. Lamouroux) J.V. Lamouroux, 1813
• Fucus ambiguus Clemente, 1807 accepted as Dictyopteris polypodioides (A.P. De Candolle) J.V. Lamouroux, 1809
• Fucus amphibius Hudson, 1778 accepted as Bostrychia scorpioides (Hudson) Montagne, 1842
• Fucus anceps Harvey & Ward ex Carruthers, 1864 accepted as Fucus distichus Linnaeus, 1767
• Fucus angulatus Gmelin
• Fucus angulatus Roussel, 1806
• Fucus angustifolius Turner, 1811 accepted as Sargassum angustifolium C. Agardh, 1820
• Fucus anomalus Pallas, 1766 accepted as Sporochnus anomalus (Pallas) M.J. Wynne, 2003
• Fucus antarcticus Chamisso, 1822 accepted as Durvillaea antarctica (Chamisso) Hariot, 1892
• Fucus antennulatus Raffeneau Delile
• Fucus antennulatus Raffeneau-Delile
• Fucus aphyllantos Gmelin
• Fucus aquifolius Turner, 1807 accepted as Sargassum aquifolium (Turner) C. Agardh, 1820
• Fucus arbuscula A.P. de Candolle, 1805
• Fucus areschougii Kjellman, 1890
• Fucus articulatus (Hudson) Lightfoot, 1777 accepted as Lomentaria articulata (Hudson) Lyngbye, 1819
• Fucus articulatus Forsskål, 1775 accepted as Hormophysa cuneiformis (J.F. Gmelin) P.C. Silva, 1987
• Fucus articulatus S.G. Gmelin, 1768
• Fucus asparagoides Woodward, 1794 accepted as Bonnemaisonia asparagoides (Woodward) C. Agardh, 1822
• Fucus asplenioides Esper, 1804 accepted as Neoptilota asplenioides (Esper) Kylin, 1956
• Fucus atomarius (Woodward) Bertoloni
• Fucus atomarius S.G. Gmelin
• Fucus australis Sonder, 1845 accepted as Myriodesma quercifolium (Bory de Saint-Vincent) J.G. Agardh, 1848
• Fucus axillaris J.G. Agardh, 1868 accepted as Fucus vesiculosus Linnaeus, 1753
• Fucus axillaris R. Brown ex Turner accepted as Seirococcus axillaris (R. Brown ex Turner) Greville, 1830
• Fucus babingtonii Harvey, 1860 accepted as Silvetia babingtonii (Harvey) E.A. Serrão, T.O. Cho, S.M. Boo & Brawley, 1999
• Fucus baccatus S.G. Gmelin, 1768 accepted as Cystoseira baccata (S.G. Gmelin) P.C. Silva, 1952
• Fucus baccifer Turner, 1802 accepted as Sargassum natans (Linnaeus) Gaillon, 1828
• Fucus bacciferus
• Fucus baccularia Mertens, 1819 accepted as Sargassum baccularia (Mertens) C. Agardh, 1824
• Fucus baillouviana S.G. Gmelin, 1768 accepted as Dasya baillouviana (S.G. Gmelin) Montagne, 1841
• Fucus balticus C. Agardh, 1814 accepted as Fucus vesiculosus Linnaeus, 1753
• Fucus bangii Hornemann, 1813 accepted as Phyllophora crispa (Hudson) P.S. Dixon, 1964
• Fucus banksii Turner, 1808 accepted as Hormosira banksii (Turner) Decaisne, 1842
• Fucus barbatus Goodenough & Woodward, 1797 accepted as Cystoseira barbata (Stackhouse) C. Agardh, 1820
• Fucus barbatus Gunnerus, 1772 accepted as Devaleraea ramentacea (Linnaeus) Guiry, 1982
• Fucus barbatus Linnaeus, 1753 accepted as Cystoseira foeniculacea (Linnaeus) Greville, 1830
• Fucus barbulatus Poiret
• Fucus bastera S.G. Gmelin, 1768
• Fucus bicornis De la Pylaie
• Fucus bicornis Gmelin
• Fucus bifidus Hudson, 1778 accepted as Rhodophyllis divaricata (Stackhouse) Papenfuss, 1950
• Fucus bifidus S.G. Gmelin, 1768 accepted as
• Fucus bifurcatus Gunnerus, 1766 accepted as Laminaria digitata (Hudson) J.V. Lamouroux, 1813
• Fucus bifurcatus Velley, 1792 accepted as Bifurcaria bifurcata R. Ross, 1958
• Fucus bipinnatus Desfontaines
• Fucus biserratus Thunberg, 1815 accepted as Sargassum fulvellum (Turner) C. Agardh, 1820
• Fucus botryocarpus Turner, 1819 accepted as Botryocarpa prolifera Greville, 1830
• Fucus botryoid Forssk.
• Fucus botryoides Turner accepted as Laurencia botryoides (C. Agardh) Gaillon, 1828
• Fucus botryoides Wulfen, 1789 accepted as Botryocladia botryoides (Wulfen) Feldmann, 1941
• Fucus bracteatus S.G. Gmelin, 1768 accepted as Gigartina bracteata (S.G. Gmelin) Setchell & N.L. Gardner, 1933
• Fucus brevifolius Poiret
• Fucus brodiei Turner accepted as Coccotylus truncatus (Pallas) M.J. Wynne & J.N. Heine, 1992
• Fucus brownii Turner, 1811 accepted as Cystophora brownii (Turner) J.G. Agardh, 1848
• Fucus bryum Strøm, 1788 accepted as Cladostephus spongiosus (Hudson) C. Agardh, 1817
• Fucus buccinalis Linnaeus, 1771 accepted as Ecklonia maxima (Osbeck) Papenfuss, 1940
• Fucus bulbosus Hudson, 1778 accepted as Saccorhiza polyschides (Lightfoot) Batters, 1902
• Fucus bullatus O.F. Müller, 1777 accepted as
• Fucus bursa-pastoris S.G. Gmelin, 1768 accepted as Gracilaria bursa-pastoris (S.G. Gmelin) P.C. Silva, 1952
• Fucus bursigerus J.G. Agardh, 1868 accepted as Fucus evanescens C. Agardh, 1820
• Fucus bursus (Linnaeus) Turner, 1811 accepted as
• Fucus buxbaumii C. Agardh
• Fucus byssoides Goodenough & Woodward, 1797 accepted as Brongniartella byssoides (Goodenough & Woodward) F. Schmitz, 1893
• Fucus cabrerae Clemente, 1807 accepted as Carpomitra costata (Stackhouse) Batters, 1902
• Fucus cactoides Turner, 1809 accepted as Caulerpa cactoides (Turner) C. Agardh, 1817
• Fucus caespitosus Stackhouse, 1795 accepted as Gelidium corneum (Hudson) J.V. Lamouroux, 1813
• Fucus callopilophorus Forsskål, 1775
• Fucus canalicularioides Clemente, 1807 accepted as Liagora distenta (Mertens ex Roth) J.V. Lamouroux, 1816
• Fucus canaliculatus Linnaeus, 1767 accepted as Pelvetia canaliculata (Linnaeus) Decaisne & Thuret, 1845
• Fucus capensis Areschoug, 1860
• Fucus capensis S.G. Gemelin, 1768 accepted as Gelidium capense (S.G. Gmelin) P.C. Silva, 1987
• Fucus capillaceus S.G. Gmelin, 1768 accepted as Pterocladiella capillacea (S.G. Gmelin) Santelices & Hommersand, 1997
• Fucus capillaris Hudson, 1778 accepted as Gloiosiphonia capillaris (Hudson) Carmichael, 1833
• Fucus capitatus Gmelin