[Phylum] [Arthropoda] Siebold, 1848 - arthropods
   Chelicerata Heymons, 1901
     Euchelicerata Weygoldt & Paulus, 1979
       [Order] †Chasmataspidida Caster & Brooks, 1956
         1 Genus †Kiaeria Størmer, 1934, incertae sedis
         2 Family †Chasmataspididae Caster & Brooks, 1956 [monotypic]
         3 Family †Diploaspididae Størmer, 1972