After Martin & Davis, 2001

Alternative, older, taxonomy after Parker, 1982

<==o Cyclopoida Burmeister, 1834 [incl. Notodelphyoida] (kyklooppiäyriäiset)
   |-- Archinotodelphyidae Lang, 1949
   |--o Ascidicolidae Torell, 1860
   |  |-- Enterocolinae [Enterocolidae]
   |  |-- Enteropsinae [Enteropsinae]
   |  `-- Schizoproctinae [Schizoproctidae; Botrylophyllidae]
   |-- Buproridae Thorell, 1859
   |-- Chordeumiidae Boxshall, 1988
   |-- Cucumaricolidae Bouligand & Delamare-Deboutteville, 1959
   |-- Cyclopidae Dana, 1846
   |-- Cyclopinidae Sars, 1913
   |-- Fratiidae Ho, Conradi & López-Conzález, 1998
   |-- Lernaeidae Cobbold, 1879
   |?- Lichomologidae [not recognized by Martin & Davis, 2001]
   |-- Mantridae Leigh-Sharpe, 1934
   |-- Notodelphyidae Dana, 1852 [Duropygidae]
   |-- Oithonidae Dana, 1852
   |-- Ozmanidae Ho & Thatcher, 1989
   |-- Speleoithonidae da Rocha & Iliffe, 1991
   `-- Thaumatopsyllidae Sars, 1913 [Thespesiopsyllidae]

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