Halecostomi Regan, 1923
Count: -
   Order †Pycnodontiformes Berg, 1937
  Count: [†f] †10f;11g;1s
     Suborder †Gyrodontoidei Nursall, 1996
    Count: [†g] †2f;3g
       Family †Gyrodontidae Berg, 1940
      Count: [†g] †1g
         Genus †Gyrodus Agassiz, 1833
        Count: -