[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Kingdom Algae L. (1753) see [unranked] Algae
     Phylum Phaeophycota see Class Phaeophyceae Hansgirg (1886)
       Class Phaeophyceae Hansgirg (1886) - brown algae
         Order Sphacelariales Migula (1908)
           Family Sphacelariaceae Decaisne (1842)
             Genus Sphacelaria H.C. Lyngbye (1819)
               Sphacelaria radicans (Dillwyn, 1809) C.Agardh (1824) see Protohalopteris radicans (Dillwyn, 1809) S.G.A. Draisma et al. (2010)