After Nelson, 1994, with species from Froese & Pauly, 2001 [“The Fishbase”]

<==o Notacanthidae (piikkiankeriaat)
   |--o †Pronotacanthus U. Cret. SWAs. Olig. Eu.
   |  `-- †P. sahalaimae
   |--o Notacanthus [Notacanthinae] ()? [6]
   |  |-- N. abbotti Fowler, 1934
   |  |-- N. bonaparte Risso, 1840 (Shortfin spiny eel)
   |  |-- N. chemnitzii Bloch, 1788 (Spiny eel)
   |  |-- N. indicus Lloyd, 1909
   |  |-- N. sexspinis Richardson, 1846 (Spiny-back eel)
   |  `-- N. spinosus Garman, 1899
   `--o Polyacanthonotinae
      |-- Lipogenys gilli Goode & Bean, 1895 [Lipogenyidae]
      `--o Polyacanthonotus ()? [N: 3]
         |-- P. africanus (Gilchrist & von Bonde, 1924)
         |-- P. challengeri (Vaillant, 1888) (Longnose tapirfish)
         |-- P. merretti Sulak, Crabtree & Hureau, 1984
         `-- P. rissoanus (De Filippi & Verany, 1857) (Small-mouth spiny eel)

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