After Carroll, 1988, Nelson, 1994, and Tyler & Sorbini, 1996, with Recent species from Froese & Pauly, 2001 [“The Fishbase”]

<==o Tetraodontiformes [Plectognathi] (jäykkäleukakalat) [circa 320 species]
   |--o †Plectocretacicoidea Tyler & Sorbini, 1996
   |  |-- †Cretatriacanthus guidottii Tyler & Sorbini, 1996 U. Cret. Eu. [Cretatriacanthidae Tyler & Sorbini, 1996]
   |  `--+-- †Plectocretacicus clarae Sorbini, 1979 U. Cret. Eu. [Plectocretacidae Tyler & Sorbini, 1996]
   |     `-- †Protriacanthus gortanii d'Erasmo, 1946 U. Cret. Eu. [Protriacanthidae Tyler & Sorbini, 1996]
   `--+?- †Cryptobalistes Olig. Eu.
      |--o Triacanthoidei [Triacanthoidea] (spikefishes & triplespines; vaarnakalamaiset)
      |  |-- Triacanthidae (naulakalat; triplespines)
      |  `-- Triacanthodidae sensu Tyler, 1980 (vaarnakalat; spikefishes) [Nelson: 11/20] [Fishbase: 11/21]
      `--o Tetraodontoidei (pufferfishes; pallokalamaiset)
         |-- Balistoidea (triggerfishes and relatives; säppikalansukuiset)
         `-- Tetraodontoidea [Gymnodontes] (pufferfishes and relatives; pallokalansukuiset)

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