organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Kingdom Protoctista Hogg, 1860
     Phylum Gamophyta
       Class Euconjugatae see Suborder Zygnematineae
         Order Zygnemoideae see Family Zygnemataceae (Meneghini) Kützing (1843)
           1 Genus Zygnema C.Agardh (1817), nom. cons.
           2 Genus Spirogyra Link (1820), nom. cons.
           3 Genus Mougeotia C.Agardh (1824), nom. cons.