Arthropoda Siebold, 1848 - arthropods Euarthropoda Subphylum Chelicerata Heymons, 1901 Euchelicerata Weygoldt & Paulus, 1979 Prosomapoda Lamsdell, 2013 Xiphosura Latreille, 1802 - horseshoe crabs Order Xiphosurida Latreille, 1802 †Bellinurina orth. inval. see Suborder Belinurina Bergström, 1975