After Hou & Bergström, 1997, and Zhang, Siveter, Waloszek & Maas, 2007, Regier, Shultz, Zwick, Hussey, Ball, Wetzer, Martin & Cunningham, 2010, and Rota-Stabelli, Campbell, Brinkmann, Edgecombe, Longhorn, Peterson, Pisani, Philippe & Telford, 2011; with additional information from Maddison & Maddison, 1995-1998 [“The Tree of Life”] and “Palaeos”

<==o Pancrustacea [Crustacea Pennant, 1777 sensu lato; Tetraconata; Crustaceomorpha] (crustaceans; äyriäiset)
   `--o Pseudocrustacea Størmer, 1944 [paraphyletic grade of primitive Crustaceomorphans]
      |?-o †Euthycarcinoidea Gall & Grauvogel, 1964 [Archicopepoda; Euthycarcinata]
      |  |?- †Synaustrus brookvalensis (Riek 1964)
      |  |?- †Schramixerxes gerem (Schram & Rolfe 1982)
      |  |?- †Kalbarria brimmellae
      |  |--o †Sottixeriformes
      |  |  |-- †Pieckoxerxes piekoae (Schram & Rolfe 1982)
      |  |  `-- †Sottyxerxes multiplex Schram & Rolfe 1982
      |  `--o †Ethycarciniformes Starobogatov, 1988
      |     |?- †Apankura machu Vaccarl, Edgecombe & Escudero, 2004
      |     |?-o †Euthycarcinus
      |     |  |-- †E. ibbenburensis
      |     |  `-- †E. kessleri Handlirsch, 1914
      |     `--o †Kottixerxidae
      |        |--o †Kottixerxes Schram, 1971
      |        |    |-- †K. gloriosus Schram, 1971
      |        |    `-- †K. anglicus Wilson & Almond, 2001
      |        `--o †Smithixerxes Schram & Rolfe, 1982
      |           |-- †S. juliarum Schram & Rolfe, 1982
      |           `-- †S. pustulosus Wilson & Almond, 2001
      |-- †Agnostida Salter, 1864 [usually regarded as primitive trilobites]
      `--+--o †Waptiida Størmer, 1944
         |  `--o †Waptiidae Walcott, 1912
         |     |?- †Pauloterminus spinodorsalis Taylor, 2002
         |     |-- †Waptia fieldensis Walcott, 1912
         |     |-- †Plenocaris plena Hou & Bergström 1997; Whittington, 1974
         |     `-- †Chuandianella ovata (Li, 1975) Hou & Bergström, 1991 [Mononotella ovata Li, 1975]
         `--o Labrophora
            |-- †Combinivalvula chengjiangensis
            |-- †Oelandocaris oelandica Müller, 1983
            |-- †Phosphatocopida Müller, 1982 [non Müller & Waloszek, 1991]
            `--o Crustacea Pennant, 1777 sensu lato (crustaceans; äyriäiset)
               |-- †Isoxys communes [Isoxyida [Isoxyda]: Isoxyidae]
               |--o Oligostraca [=? Maxillopoda sensu Maddison & Maddison, 1998]
               |  |-- Ostracoda Latreille, 1802 (ostracods, seed shrimps; raakkuäyriäiset)
               |  `--+-- Mystacocarida Pennack & Zinn, 1943
               |     `--o Ichthyostraca
               |        |-- Pentastomida Diesing, 1836 [are Maxillopods (Martin & Davis, 2001)?] (pentastomids, tongue worms; punkkimadot)
               |        `--+?- †Halicyna Gall & Grauvogel, 1967 [Cyclida] (cycloids)
               |           `-- Branchiura Thorell, 1864 (fish lice; kalatäit)
               `--o Altocrustacea
                  |?- †Rehbachiella kinnekullensis Waloszek, 1993
                  |?- †Yicaris dianensis Zhang, Siveter, Waloszek & Maas, 2007
                  |--o Miracrustacea
                  |  |-- Hexapoda Latreille, 1825 [incl. Insecta] (sixlegged arthropods; kuusjalkaiset niveljalkaiset)
                  |  `--o Xenocarida
                  |     |-- Remipedia Yager, 1981 (remipedes; remipedit)
                  |     `--o Cephalocarida Sanders, 1955 (horseshoe shrimps)
                  |        `--o Brachypoda Birshtey, 1960
                  |           `--o Hutchinsoniellidae Sanders, 1955 [incl. Lightiellidae Jones, 1961]
                  |              |-- Chiltoniella elongata
                  |              |-- Hampsonellus brasiliensis
                  |              |-- Hutchinsoniella macracantha Sanders, 1955
                  |              |--o Lightiella Jones, 1961
                  |              |  |-- L. serendipita Jones, 1961
                  |              |  |-- L. incisa Gooding, 1963
                  |              |  |-- L. monniotae Cals & Delamare Deboutteville, 1970
                  |              |  |-- L. floridana
                  |              |  `-- L. magdalenina
                  |              `--o Sandersiella
                  |                 |-- S. acuminata Shiino, 1965
                  |                 |-- S. bathyalis
                  |                 |-- S. calmani
                  |                 `-- S. kikuchii
                  `--o Vericrustacea
                     |-- Branchiopoda Latreille, 1817 (branchiopods; kidusjalkaiset)
                     `--o Multicrustacea
                        |-- Copepoda Milne-Edwards, 1840 (copepods; hankajalkaiset)
                        `--o Communostraca
                           |-- Thecostraca Gruvel, 1905 [Branchiura in partim] [incl. Cirripedia Burmeister, 1834 (siimajalkaiset)]
                           `-- Malacostraca Latreille, 1802 (malacostracans; kuoriäyriäiset)

Note:

Agnostida Salter, 1864 is often classified as basal order of trilobites. Recent phylogenetic analysis and papers universally refer to Hou & Bergström (1997) for placing them as pan-crustaceans.

After Martin & Davis, 2001


<==o Crustacea
   |-- †Isoxys
   |?- Pentastomida
   `--+-- Remipedia
      |--o Entomostraca
      |  |?- †Rehbachiella
      |  |?- †Yicaris
      |  |-- Branchiopoda
      |  |-- Cephalocarida
      |  `--o Maxillopoda sensu Maddison & Maddison, 1998
      |     |-- Maxillopoda
      |     `-- Ostracoda
      `-- Malacostraca

Reference(s):