Kingdom Protoctista Hogg, 1860
   Phylum Chlorophyta Pascher (1914) - green algae
     ?Class Prasinophyceae T. Christensen, 1962 ex Ø. Moestrup & J. Throndsen (1988) - prasinophytes see [unranked] prasinophytes
       Order Pyramimonadales Chadefaud
         1 Family Pterospermataceae see Family Halosphaeraceae Haeckel (1894)
         2 Family Pyramimonadaceae Korshikov see Family Halosphaeraceae Haeckel (1894)
         3 Family Mesostigmataceae Fott ex Moestrup & Throndsen