After Parker, 1982, and “Wikispecies”

<==o Acoela [Acoelomorpha]
   |--o Actinoposthiidae Hooge, 2001
   |  |-- Actinoposthia
   |  |-- Archactinoposthia
   |  |-- Atriofronta
   |  |-- Childianea
   |  |-- Microposthia
   |  |-- Paractinoposthia
   |  |-- Paraproporus
   |  |-- Pelophila
   |  |-- Philactinoposthia
   |  |-- Pseudactinoposthia
   |  `-- Tetraposthia
   |--o Anaperidae Dörjes, 1968
   |  |-- Achoerus
   |  |-- Anaperus
   |  |-- Conaperta
   |  |-- Neochildia
   |  |-- Oxyposthia
   |  |-- Philachoerus
   |  `-- Pseudanaperus
   |--o Antigonariidae
   |  `-- Antigonaria arenaria Dorjes 1968
   |--o Antroposthiidae Faubel, 1976
   |  |-- Antroposthia
   |  |-- Convoluella
   |  `-- Unantra
   |--o Childiidae
   |  `-- Childia Graff, 1910 [Paraphanostoma Westblad, 1942; Tekle et al.,2005]
   |--o Convolutidae
   |  |-- Adenopea
   |  |-- Amphiscolops
   |  |-- Brachypea
   |  |-- Convoluta
   |  |-- Haplodiscus
   |  |-- Heterochaerus
   |  |-- Oligochoerus
   |  |-- Polychoerus
   |  |-- Stomatricha
   |  |-- Waminoa
   |  `-- Wulguru
   |--o Dakuidae Hooge, 2003
   |  `-- Daku Hooge, 2003
   |-- Diopisthoporidae
   |-- Hallangiidae
   |--o Haploposthiidae
   |  |-- Deuterogonaria
   |  |-- Paranaperus
   |  |-- Praeanaperus
   |  `== other genera?
   |--o Hofsteniidae
   |  |-- Hofstenia
   |  |-- Hofsteniola
   |  `-- Marcusiola
   |--o Isodiametridae Hooge & Tyler, 2005 [Aphanostomidae]
   |  |-- Isodiametra Hooge & Tyler, 2005
   |  `-- Pharyngia furva Nilsson, Wallberg & Jondelius, 2011 
   |--o Mecynostomidae
   |  |-- Limnoposthia
   |  |-- Stylomecynostomum
   |  `== other genera?
   |-- Nadinidae
   |-- Otocelididae [Otocelidae]
   |-- Paratomellidae
   |--o Polycanthiidae Hooge, 2003
   |  `--  Polycanthus Hooge, 2003 [nec Polycanthus Swainson, 1838; nec Polycanthus Swainson, 1839]
   |-- Proporidae
   |--o Sagittiferidae
   |  |-- Antrosagittifera
   |  |-- Convolutriloba
   |  |-- Praesagittifera
   |  |-- Sagittifera
   |  `-- Symsagittifera
   |--o Solenofilomorphidae Dörjes, 1968
   |  |-- Endocincta
   |  |-- Fusantrum
   |  |-- Myopea
   |  |-- Oligofilomorpha
   |  `-- Solenofilomorpha
   `--o Taurididae Kostenko, 1989
      `-- Taurida fulvomaculata (Ax, 1959) Kostenko, 1989 [nec Taurida Sellier de Civrieux & Dessauvagie, 1965 (Foraminifera)]

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