Class †Placodermi McCoy, 1848
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   Order †Arthrodira Woodward, 1891 see [unranked] Arthrodira Woodward, 1891
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     Suborder †Brachythoraci Gross, 1932
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       .1 Genus †Dunkleosteus Lehman, 1956
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       .2 Genus †Coccosteus Agassiz, 1844
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       .3 Genus †Tafilalichthys Lehman, 1956
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       .4 Genus †Melanosteus Lelièvre & Goujet, 1987
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       .5 Genus †Gymnotrachelus Dunkle & Bungart, 1939
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       .6 Genus †Heintzichthys Whitley, 1933
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       .7 Genus †Holonema Newberry, 1890
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       .8 Genus †Goodradigbeeon White, 1978
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       .9 Genus †Livosteus Obrucheva, 1962
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       1 Genus †Maideria H. Lelièvre, 1995, incertae sedis
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       2 Genus †Buchanosteus Stensiö, 1945, incertae sedis
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       3 †"Migmatocephala"
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       4 †"Eubrachythoraci" Miles, 1971
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