[Phylum] [Arthropoda] Siebold, 1848 - arthropods
   Chelicerata Heymons, 1901
     Euchelicerata Weygoldt & Paulus, 1979
       Pantetrapulmonata Shultz, 2007
         [Order] †Trigonotarbida Petrunkevitch, 1949
           Family †Aphantomartidae Petrunkevitch, 1945
             1 Genus †Alkenia Størmer, 1970
             2 Genus †Aphantomartus Pocock, 1911