Chelicerata Heymons, 1901
Count: 2c;12o; †6o;2f;23g
   †Trigonotarbida Petrunkevitch, 1949
  Count: [†g] †9f;37g [24 Dec 2020]
     Family †Aphantomartidae Petrunkevitch, 1945
    Count: [†g] †2g [24 Dec 2020]
       Genus †Alkenia Størmer, 1970
      Count: -