After Parker, 1982 [Slightly modified after Martin & Davis, 2001]

<==o Copepoda Milne-Edwards, 1840
   |-- Calanoida Sars, 1903 (keijuhankajalkaiset)
   |?-o Misophrioida Gurney, 1933 [from Martin & Davis, 2001, not recognized by Parker, 1982]
   |  |-- Misophriidae Brady, 1878
   |  |-- Palpophriidae Boxshall & Jaume, 2000
   |  `-- Spaleophriidae Boxshall & Jaume, 2000
   |-- Harpacticoida (ryömijähankajalkaiset)
   |-- Cyclopoida Burmeister, 1834 (kyklooppiäyriäiset)
   |--o Notodelphyoida
   |  `-- Notodelphyidae Dana, 1852
   |?-o Mormonilloida Boxshall, 1979
   |  `-- Mormonillidae Giesbrecht, 1893 [from Martin & Davis, 2001, not recognized by Parker, 1982]
   |--o Monstrilloida Sars, 1901 (aaveäyriäiset)
   |  |--o Cyclopimorpha
   |  |  `-- Thespesiopsyllidae
   |  `--o Genuina
   |     `-- Monstrillidae Dana, 1849
   `--o Calicoida [Siphonostomatoida Thorell, 1859] (galicusäyriäiset)
      |-- Caligidae Burmeister, 1834
      |-- Trebiidae Wilson, 1905
      |-- Euryphoridae Wilson, 1905
      |-- Pandaridae Milne-Edwards, 1840
      |-- Cecropidae Dana, 1849
      |-- Anthosomidae
      |-- Eudactylinidae Wilson, 1922
      |-- Pseudocycnidae Wilson, 1922
      |-- Dichelesthiidae Milne-Edwards, 1840
      |-- Lernaeidae Cobbold, 1879 (pussihankajalkaiset)
      `-- Pennellidae Burmeister, 1834

Reference(s):