After Parker, 1982, Brusca, 1997-1999 [“The Tree of Life”], and Martin & Davis, 2001

<==o Peracarida Calman, 1904 (isopods, amphipods and relatives; siirat & katkat)
   |?-o †Pygocephalomorpha
   |  |?- †Bellocaris newfoundlandensis Fong, 1972
   |  |?- †Hoplita ginsburgi (Fabre & Huard, 1967) Pineiro, Morosi & Ramos, 2012 [Pygaspis ginsburghi Fabre & Huard, 1967]
   |  |?-o †Pygaspis Beurlen, 1934
   |  |  |-- †P. brasiliensis Beurlen, 1934
   |  |  `-- †P. quadrata Beurlen, 1934
   |  |-- †Jerometichenoria grandis Schram, 1978 [Jerometichenoriidae Schram, 1978]
   |  |--o †Notocarididae Brooks, 1962
   |  |  |-- †Notocaris tapscotti (Woods, 1923) Broom, 1931
   |  |  `--o †Paulocaris Clarke, 1920
   |  |     |-- †P. pachoecoi Clarke, 1920
   |  |     `-- †P. schrami Hotton, Feldmann, Hook & Dimichele, 2002
   |  |--o †Pygocephalidae Brooks, 1962
   |  |  |-- †Anthracaris gracilis (Meek & Worthen, 1865) Brooks, 1962
   |  |  |--o †Mamayocaris Brooks, 1962
   |  |  |  |-- †M. jaskowskii Schram, 1974
   |  |  |  |-- †M. jepseni Brooks, 1962
   |  |  |  `-- †M. serendipitous Hotton, Feldmann, Hook & Dimichele, 2002
   |  |  `--o †Pygocephalus Huxley, 1857 [Brooksocaris Birshteyn, 1967]
   |  |     |-- †P. aisenvergi (Birshteyn, 1967) [Brooksocaris aisenvergi Birshteyn, 1967]
   |  |     |-- †P. cooperi Huxley, 1857
   |  |     `-- †P. dubius (Prestwich, 1840)
   |  |--o †Tealliocarididae
   |  |  |--o †Pseudotealliocaris Brooks, 1962
   |  |  |  |-- †P. caudafimbriata (Copeland, 1957) [Tealliocaris caudafimbriata Copeland, 1957; Tealliocaris barathrota Copeland, 1957; Tealliocaris belli Copeland, 1957]
   |  |  |  |-- †P. etheridgei (Peach, 1882)
   |  |  |  |-- †P. holthuisi Irham, Schram & Vonk, 2010
   |  |  |  `-- †P. palincsari Schram, 1988
   |  |  `--o †Tealliocaris Peach, 1908
   |  |     |-- †T. etheridgei Peach, 1908
   |  |     |-- †T. formosa (Peach, 1882)
   |  |     |-- †T. loudensis Peach, 1908
   |  |     |-- †T. robusta Peach, 1908
   |  |     |-- †T. tarrassiana Peach, 1908
   |  |     `-- †T. woodwardi (Etheridge, 1877)
   |  `--o †Tylocarididae Taylor, Yan-Bin & Schram, 1998
   |     |-- †Chaocaris chinensis  Shen, 1983
   |     |-- †Fujianocaris bifurcatus Taylor, Yan-Bin & Schram, 1998
   |     |--o †Liocaris Beurlen, 1931
   |     |  |-- †L. angustata Beurlen, 1931
   |     |  `-- †L. huenei Beurlen, 1931
   |     |--o †Pseudogalathea Peach, 1883
   |     |  |-- †P. macconochei (Etheridge, 1879)
   |     |  |-- †P. ornatissima (Peach, 1882)
   |     |  `-- †P. rotunda Peach, 1883
   |     `-- †Tylocaris asiaticus Taylor, Yan-Bin & Schram, 1998
   |-- Mysida Haworth, 1825 [nec Boas, 1883] [Mysidacea] (halkoisjalkaiset)
   |-- Thermosbaenacea Monod, 1927
   |-- Lophogastrida Sars, 1870
   `--+--o Spalaeogriphidae Gordon, 1957 [Spelaeogriphacea Gordon, 1957]
      |  |-- Acadiocaris
      |  |--o Mangkurtu Poore & Humphreys, 1998
      |  |  |-- M. kutjarra Poore & Humphreys, 2003
      |  |  `-- M. mityula Poore & Humphreys, 1998
      |  |-- Potiicoara brasiliensis Pires, 1987
      |  `-- Spelaeogriphus lepidops Gordon, 1958
      |--o Mictacea Bowman, Garner, Hessler, Iliffe & Sanders, 1985
      |  |-- Hirsutiidae Sanders, Hessler & Garner, 1985
      |  `-- Mictocarididae Bowman & Iliffe, 1985
      |-- Tanaidacea Dana, 1849
      |-- Amphipoda Latreille, 1816 (amphipods; katkat)
      |--o Cumacea Krøyer, 1846
      |  |?- Archaeocuma [Archaeocumidae Bacescu, 1972] [not recognized by Martin & Davis, 2001]
      |  |-- Bodotriidae Scott, 1901
      |  |-- Ceratocumatidae Calman, 1905
      |  |-- Diastylidae Bate, 1856
      |  |-- Gynodiastylidae Stebbing, 1912
      |  |-- Lampropidae Sars, 1878
      |  |-- Leuconidae  Sars, 1878
      |  |-- Nannastacidae Bate, 1866
      |  `-- Pseudocumatidae Sars, 1878
      `-- Isopoda Latreille, 1817 (isopods; aitosiirat)

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