Phylum Euarthropoda Lankester, 1904 see [unranked] Euarthropoda
   Subphylum †Artiopoda Hou & Bergström, 1997
     Superclass †Vicissicaudata Ortega-Hernández, Legg & Braddy, 2013
       1 Genus †Aglaspis Hall, 1862
       2.1 Genus †Emeraldella Walcott, 1912
       2.2 Genus †Sidneyia Walcott, 1911