Familia and genera from Wikipedia

<==o Ceriantharia [Ceriantipatharia in partim] (Tube-dwelling anemones)
   |--o Penicilaria
   |  `--o Arachnactidae McMurrich, 1910
   |     |-- Anactinia Annandale, 1909
   |     |-- Arachnactis Sars, 1846
   |     |-- Arachnanthus Carlgren, 1912
   |     |-- Dactylactis van Beneden, 1897
   |     |-- Isapiactis Carlgren, 1924
   |     |-- Isarachnactis Carlgren, 1924
   |     |-- Isarachnanthus Carlgren, 1924
   |     |-- Isovactis
   |     |-- Ovactis
   |     `-- Paranactinia
   `--o Spirularia
      |--o Botrucnidiferidae Carlgren, 1912
      |  |-- Angianthula Leloup, 1964
      |  |-- Atractanthula Leloup, 1964
      |  |-- Botracnidifer
      |  |-- Botruanthus
      |  |-- Botrucnidiata Leloup, 1932
      |  |-- Botrucnidifer
      |  |-- Calpanthula
      |  |-- Cerianthula Beneden, 1898
      |  |-- Gymnanthula Leloup, 1964
      |  |-- Hensenanthula
      |  |-- Ovanthula
      |  `-- Sphaeranthula
      `--o Cerianthidae Milne-Edwards & Haime, 1852
         |-- Anthoactis Leloup, 1932
         |-- Apiactis Beneden, 1898
         |-- Bursanthus
         |-- Ceriantheomorphe
         |-- Ceriantheopsis Carlgren, 1912
         |-- Cerianthus Delle Chiaje, 1830
         |-- Engodactylactis
         |-- Isodactylactis
         |-- Nautanthus
         |-- Pachycerianthus Roule, 1904
         |-- Paradactylactis
         |-- Parovactis
         |-- Peponactis
         |-- Plesiodactylactis
         |-- Sacculactis
         |-- Solasteractis
         |-- Synarachnactis Carlgren, 1924
         |-- Syndactylactis
         `-- Trichactis

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