living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Tardigrada Doyère, 1840 - tardigrades
           Order Heterotardigrada Marcus, 1927 see Class Heterotardigrada Marcus, 1927
             Suborder Arthrotardigrada Marcus, 1927 see Order Arthrotardigrada Marcus, 1927
               Family Stygarctidae Schulz, 1951
                 1 Genus Stygarctus Schulz, 1951
                 2 Genus Parastygarctus Renaud-Debyser, 1965