After Parker, 1982, Brusca & Riseman, 1997-1998 [“The Tree of Life”] and Martin & Davis, 2001

<==o Isopoda Latreille, 1817 (aitosiirat)
   |--o Phreatoicidea Stebbing, 1893
   |  |--o Amphisopodidae Nicholls, 1943 [Amphisopidae]
   |  |  |-- Amphisopodinae
   |  |  |-- Hypsimetopodinae [Hypsimetopodidae]
   |  |  |-- Mesamphisopodinae [Mesamphisopodidae]
   |  |  `-- Phreatoicopsidinae [Phreatoicopsididae]
   |  |-- Nichollsiidae Tiwari, 1955
   |  `-- Phreatoicidae Chilton, 1891
   `--+--o Asellota sensu Wägele, 1983
      |  |-- Asellota Latreille, 1802
      |  `--o Microcerberidea Lang, 1961
      |     |-- Atlantasellidae Sket, 1980 [monogeneric]
      |     `-- Microcerberidae Karaman, 1933
      `--+--o Oniscoidea sensu Brusca & Wilson, 1991
         |  |-- Calabozoidae Van Lieshout, 1983 [Calabozoidea Van Lieshout, 1983]
         |  `-- Oniscoidea Latreille, 1802 (terrestrial isopods; maasiirat, tarhasiirat)
         `--+--o Valvifera Sars, 1882
            |  |-- Antarcturidae Poore, 2001
            |  |-- Arcturidae Dana, 1849 [incl. ]Amesopidae]
            |  |-- Arcturididae Poore, 2001
            |  |-- Austrarcturellidae Poore & Bradsley, 1992
            |  |-- Chaetilidae Dana, 1849
            |  |-- Holidoteidae Wägele, 1989
            |  |-- Holognathidae Thompson, 1904
            |  |-- Idoteidae Samouelle, 1819 (kilkit)
            |  |-- Pseudidotheidae Ohlin, 1901
            |  |-- Rectarcturidae Poore, 2001
            |  `-- Xenarcturidae Sheppard, 1957
            `--o Flabellifera Sars, 1882 [paraphyletic sensu Brusca & Riseman, 1997-1998]
               |?- Ancinidae Dana, 1852
               |?- Bathynomidae [not recognized by Martin & Davis, 2001]
               |?- Excorallanidae [not recognized by Martin & Davis, 2001]
               |?- Gnathiidae Leach, 1814 (fish-parasitic isopods; kalaloissiirat) [Gnathiidea]
               |?- Hadromastacidae Bruce & Müller, 1991
               |?- Tecticepitidae Iverson, 1982
               |-- Sphaeromatidae Latreille, 1825
               `--+--+-- Epicaridea Latreille, 1831 (shrimp-parasitic isopods; katkaravunloissiirat)
                  |  `-- Nathiidea
                  |--+-- Limnoriidae White, 1850
                  |  `-- Lynseiidae [not recognized by Martin & Davis, 2001]
                  |--+-- Bathynataliidae Kensley, 1978
                  |  `--+-- Keuphyliidae Bruce, 1980
                  |     `--+-- Plakarthriidae Hansen, 1905 (1887) [Chelonidiidae Pfeffer, 1887]
                  |        `-- Serolidae Dana, 1852
                  `--o Cymothoida Leach, 1814 sensu Wägele, 1989
                     |?- Argathonidae [not recognized by Martin & Davis, 2001]
                     |-- Cirolanidae Dana, 1852
                     |-- Phoratopodidae Hale, 1925
                     `--+--o Anthuridea Monod, 1922
                        |  |-- AntheluridaePoore & Lew Ton, 1988
                        |  |-- Anthuridae Leach, 1814
                        |  |-- Expanathuridae Poore, 2001 [Expananthuridae?]
                        |  |-- Hyssuridae Wägele, 1981
                        |  |-- Leptanthuridae Poore, 2001
                        |  `-- Paranthuridae Menzies & Glynn, 1968
                        `--+-- Anuropidae Stebbing, 1893
                           |-- Protognathiidae Wägele & Brandt, 1988
                           `--+-- Corallanidae Hansen, 1890
                              |-- Tridentellidae Bruce, 1984
                              `--+-- Aegidae White, 1850
                                 `-- Cymothoidae [not recognized by Martin & Davis, 2001]

Reference(s):