After Carroll, 1988 and Frickhinger, 1995

<==o †Pygopteridae
   |--o †Nematoptychius Miss. Eu.
   |  `-- †N. greenocki
   `--o †Pygopterus M. Perm. Gr. U. Perm. L. Trias. Eu. L. Trias. SAf. Spits.
      `-- †P. humboldti

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