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 Halechiniscidae Thulin, 1928
                 1 Genus Actinarctus Schulz, 1935
                 2 Genus Echinursellus Iharos, 1968, nom. dub.
                 3 Genus Halechiniscus Richters, 1908
                 4 Genus Pleocola Cantacuzène, 1951
                 5 Genus Tanarctus Renaud-Debyser, 1959
                 6 Genus Bathyechiniscus Steiner, 1926
                 7 Genus Styraconyx Thulin, 1942
                 8 Genus Tetrakentron Cuénot, 1892
                 9 Genus Florarctus Delamare Deboutteville & Renaud-Mornant, 1965