Phylum Arthropoda Siebold, 1848 - arthropods Subphylum †Artiopoda Hou & Bergström, 1997 Superclass †Vicissicaudata Ortega-Hernández, Legg & Braddy, 2013 Order †Aglaspidida Walcott, 1911 Genus †Beckwithia Resser, 1933