<==o Eurypterida Burmeister, 1843 (meriskorpionit; seascorpions)
   |?- †Glyptoscorpius
   |--o †Eurypteracea Burmeister, 1843
   |  |-- †Hughmilleriidae
   |  |-- †Pterygotidae
   |  |-- †Eurypteridae
   |  |-- †Carcinosomatidae
   |  |-- †Mixopteridae
   |  `-- †Megalograptidae
   `--o †Stylonauracea Diener, 1924
      |-- †Stylonuridae
      |-- †Dolichoteridae
      |-- †Rhenopteridae
      `-- †Mycteropidae

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