Halecostomi Regan, 1923
   Order †Pycnodontiformes Berg, 1937
     Suborder †Pycnodontoidei Nursall, 1996
       Family †Brembodontidae Tintori, 1980
         1 Genus †Brembodus Tintori, 1980
         2 Genus †Eomesodon Woodward, 1918