Opisthokonta Cavalier-Smith 1987, nom. cl. inval. see Clade Opisthokonta Cavalier-Smith 1987 [Simpson & Medina 2020]
   Metazoa Haeckel 1874 - multicellular animals see Kingdom Animalia Linnaeus, 1758
     Porifera Grant, 1836 - sponges
       Silicea Bowerbank, 1864 - siliceous sponges see [unranked] Silicispongia Schmidt, 1862
         1 Hexactinellida Schmidt, 1870 see Class Hexactinellida Schmidt, 1870
         2 Demospongia see [unranked] Demospongiae Sollas, 1885 [Borchiellini et al., 2004]