[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Phylum Platyhelminthes Gegenbaur, 1859 - flatworms
     Class Turbellaria Ehrenberg, 1831 - planarians see Subphylum Turbellaria Ehrenberg, 1831
       Order Acoela Uljanin, 1870 - acoels see Class Acoela Uljanin, 1870
         01 Family Anaperidae Dörjes, 1968
         02 Family Antigonariidae Dörjes, 1968
         03 Family Antroposthidae see Family Antroposthiidae Faubel, 1976
         04 Family Childiidae Dörjes, 1968
         05 Family Convolutidae Graff, 1905
         06 Family Diopisthoporidae Westblad, 1940
         07 Family Hallangidae see Family Hallangiidae Westblad, 1946
         08 Family Haploposthiidae Westblad, 1948
         09 Family Hofsteniidae Bock, 1923
         10 Family Mecynostomidae Dörjes, 1968
         11 Family Nadinidae Dörjes, 1968
         12 Family Otocelididae Westblad, 1948
         13 Family Paratomellidae Dörjes, 1966
         14 Family Proporidae Graff, 1882
         15 Family Sagittiferidae Kostenko & Mamkaev, 1990
         16 Family Solenofilomorphidae Dörjes, 1968
         17 Family Taurididae Kostenko, 1989