After Hou & Bergström, 1997, Whittington, Chang, Dean, Fortey, Jell, Laurie, Palmer, Repina, Rushton & Shergold, 1997 and Gon III, 2002

<==o †Eodiscina Kobayashi, 1939 [nom. correct. Moore, 1959 pro Eodiscidi Kobayashi, 1939a]
   `--o †Eodiscoidea Raymond, 1913 [nom. transl. Jell, 1975, ex Eodiscidae Raymond, 1913b] [Eodiscidea Richter, 1932; Dawsoniidea Kobayashi, 1943]
      |--o †Tsunyidiscus W. Chang, 1966 [taxonomic history] [Tsunyidiscidae S. Zhang, 1980]
      |  |-- †T. niutitangensis (W. Zhang, 1964) [taxonomic history]
      |  |-- †T. armatus (S. Zhang & Zhu in W. Zhang, Lu, et al., 1980) [taxonomic history]
      |  |-- †T. liangshanensis (W. Zhang in W. Zhang, Lu, et al., 1980) [taxonomic history]
      |  |-- †T. planilimbatus (S. Li, 1980) [taxonomic history]
      |  |-- †T. orientalis (W. Zhang, 1953) [taxonomic history]
      |  |-- †T. longquanensis (S. Zhang & Zhu in W. Zhang, Lu, et al., 1980) [taxonomic history]
      |  `-- †T. chintingshanensis (Lu, 1942) [taxonomic history]
      |-- †Hebediscidae Kobayashi, 1944a [nom. transl. Jell in Whittington, et al., 1997, ex Hebediscinae Kobayashi, 1944a] [Delgadoiinae Kobayashi, 1943; Pagetiellinae S. Zhang in W. Zhang, Lu, et al., 1980; Dicerodiscinae S. Zhang in W. Zhang, Lu, et al., 1980]
      |-- †Calodiscidae Kobayashi, 1943 [nom. transl. Öpik, 1975a ex Calodiscinae Kobayashi, 1943] [Brevidiscinae Kobayashi, 1943; Neocobboldinae S. Zhang, in W. Zhang, Lu et al., 1980]
      |-- †Weymouthiidae Kobayashi, 1943 emend. Jell, 1975a [ladadiscinae Soloviev, 1964]
      |-- †Yukoniidae S. Zhang, 1980 [nom. transl. et emend. Jell, in Whittington et al., 1997 ex Yukoniinae S Zhang in W. Zhang, Lu et al., 1980]
      `-- †Eodiscidae Raymond, 1913 [Eodiscidae Raymond, 1913b emend. Jell, 1975a] [Dawsoniidae Resser, 1937; Pagetidae Kobayashi, 1935; Aulacodiscidae Hupé, 1954; Opsidiscidae Hupé, 1953b; Pagetiellinae S. Zhang in W. Zhang, Lu et al., 1980]

Eodiscina incertae sedis:

Discagnostus Öpik, 1963 [possibly agnostid]
        †D. spectator Öpik, 1963

Note:

Agnostida sensu lato [Agnostina & Eodiscina] have usually been classified as primitive trilobites. Hou & Bergström (1997) clearly state that, in their opinion, Agnostida sensu lato as traditionally defined and treated in the latest edition of “Treatise“ is actually a polyphyletic taxon, Eodiscina being a group of primitive trilobites and Agnostina an anomalous group of early Crustacean-like arthropods.

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