[living organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryota Whittaker & Margulis, 1978 see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Bilateria Hatschek, 1888 - bilaterians
         Infrakingdom Protostomia Grobben, 1908
           Superphylum Ecdysozoa Aguinaldo, Turbeville, Linford, Rivera, Garey, Raff & Lake, 1997
             Phylum Arthropoda Siebold, 1848 - arthropods
               Subphylum Chelicerata Heymons, 1901
                 Class Merostomata Dana, 1852 [monotypic] - horseshoe crabs see Class Xiphosura Latreille, 1802
                   Order Xiphosura Latreille, 1802 see Class Xiphosura Latreille, 1802