After Carroll, 1988

<==o †Arthrodira Woodward, 1891 (arthrodires; panssarihait)
   |--o †Actinolepina Miles, 1973
   |  |-- †Wuttagoonaspis fletsheri [Wuttagooaspina: Wuttagoonaspidae]
   |  `-- †Actinolepidae Gross, 1940
   `--+--o Phlyctaenioidei Miles, 1973
      |  |-- †Holonematidae [Holonematiina:]
      |  `--o †Phlyctaeniina Miles, 1973 sensu Denison, 198 [Phlyctaenii]
      |     |?-o †Williamsaspidae White, 1952 [Williamsaspidoidea White, 1952] [Brachythoraci sensu Young, 2009]
      |     |  |-- †Williamsaspis bedfordi White, 1952; E.Dev. Aust.
      |     |  `--o †Elvaspis Young, 2009; E.Dev. Aust.
      |     |     |-- †E. tuberculata Young, 2009
      |     |     `-- †E. whitei Young, 2009
      |     |-- †Groelandaspididae Obruchev, 1964
      |     `-- †Phlyctaeniidae
      `--o †Brachythoraci
         |--o †Heterosteidae [Heterosiina:, Heterosteoidei]
         |  |-- †Herasmius [Herasrnius (an OCR typo)] M.Dev. Spits.
         |  `--o †Heterosteus [Chelonichthys, Heterostius, Ichthyosauroides] M.Dev. Eu. EEu. Gr. Spits.
         |     `-- †H. groenlandicus (Stensiö & Säve-Söderbergh, 1938) [Heterostius groenlandicus Stensiö & Säve-Söderbergh, 1938]
         `-- †Coccosteina [Coccosteoidei, Brachythoraci]

Arthrodira incertae sedis:

Antarctolepis M.Dev. Ant.
    †Aspidichthys [Anomalichthys, Aspidophorus] L.Dev. Eu. NA. NAf. SWAs.
    †Atlantidosteus E.Dev. NAf.
    †Carolowilhelmina geognostica Mark-Kurik & Carls, 2002; M.Dev WEu.
    †Callognathus L.Dev. NA.
    †Copanognathus L.Dev. NA.
    †Glyptaspis L.Dev. NA.
    †Golshanichthys Lelièvre et. al, 1981
    †Grazosteus ?M.Dev. Eu.
    †Hollardosteus M.Dev. NAf.
    †Laurentaspis M.Dev. NA.
    †Machaerognathus L.Dev. NA.
    †Murmur [Euptychaspis, Ptychaspis] E.Dev. Eu.
    †Overtonaspis E.Dev. Eu.
    †Phylactaenium acadicusPrescottaspis E.Dev. Eu.
    †Qataraspis E.Dev. SWAs.
    †Taunaspis E.Dev. Eu.
    †Timanosteus L.Dev. CAs.
    †Trachosteus L.Dev. NA.
    †Wheathillaspis E.Dev. Eu.

Reference(s):