Halecostomi Regan, 1923
Count: -
   Order †Pycnodontiformes Berg, 1937
  Count: [†f] †10f;11g;1s
     Suborder †Pycnodontoidei Nursall, 1996
    Count: [†f] †2f;3g
       Family †Pycnodontidae Agassiz, 1833
      Count: †1g
         Genus †Macromesodon Blake, 1905
        Count: -