Chelicerata Heymons, 1901
Count: 2c;12o; †6o;2f;23g
   Scorpiones Koch, 1837 - scorpions
  Count: [g†g] 15f;5g; †43f;92g [27 Dec 2020]
     Orthosternina Pocock, 1911 see Infraorder Orthosterni Pocock, 1911
    Count: [g†g] 15f;5g; †8f;30g [27 Dec 2020]
       Superfamily Chactoidea Pocock, 1893
      Count: [g†g] 12f;1g; †1f;9g [27 Dec 2020]
         Family Hemiscorpiidae Pocock, 1893
        Count: [†g] †1g [27 Dec 2020]
           Genus †Protoischnurus Carvalho & Lourenço, 2001
          Count: -