[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Echinoderma
         Branch Ambulacrata
           Class Echinoidea (Leske, 1778) - sea urchins and sand dollars
             Grade Palæechini
               Order Melonitidæ
                 1 Genus Melonites Norwood & Owen, 1846, nom. illeg.