Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         Superphylum Articulata Cuvier see Supraphylum Articulata Cuvier
           Phylum Arthropoda Siebold, 1848 - arthropods
             Subphylum Chelicerata Heymons, 1901
               Class Merostomata Dana, 1852 - horseshoe crabs see Class Xiphosura Latreille, 1802
                 Order Xiphosura Latreille, 1802 see Class Xiphosura Latreille, 1802
                   1 Family Limulidae Leach, 1819