Neornithes Gadow, 1893 - living birds
   Neognathae Pycraft 1900 see Cohort Neognathae Pycraft, 1900
     Galloanserae Sibley, Ahlquist & Monroe Jr., 1988 see Subcohort Galloanserae Sibley, Ahlquist & Monroe Jr., 1988
       [Order] Galliformes Temminck, 1820 - fowl
         phasianoids see Superfamily Phasianoidea Vigors, 1825
           Family Phasianidae Vigors, 1825 - turkeys, grouse, pheasants, partridges
             Subfamily Tetraoninae Vigors - grouse see Family Tetraonidae Vigors, 1825
               Genus Lagopus Brisson, 1760 - ptarmigan
                 Lagopus muta (Montin, 1781) - rock ptarmigan
                   01 Lagopus muta mutaᵀ (Montin, 1781)
                   02 Lagopus muta millaisi Hartert, 1923
                   03 Lagopus muta helvetica (Thienemann, 1829)
                   04 Lagopus muta pyrenaica Hartert, 1921
                   05 Lagopus muta pleskei Serebrovsky, 1926
                   06 Lagopus muta nadezdae Serebrovsky, 1926
                   07 Lagopus muta ridgwayi Stejneger, 1884
                   08 Lagopus muta kurilensis Kuroda, 1924
                   09 Lagopus muta japonica Clark, 1907
                   10 Lagopus muta evermanni Elliot, 1896
                   11 Lagopus muta townsendi Elliot, 1896
                   12 Lagopus muta gabrielsoni Murie, 1944
                   13 Lagopus muta sanfordi Bent, 1912
                   14 Lagopus muta chamberlaini Clark, 1907
                   15 Lagopus muta atkhensis Turner, 1882
                   16 Lagopus muta yunaskensis Gabrielson & Lincoln, 1951
                   17 Lagopus muta nelsoni Stejneger, 1884
                   18 Lagopus muta dixoni Grinnell, 1909
                   19 Lagopus muta rupestris (Gmelin, 1789)
                   20 Lagopus muta welchi Brewster, 1885
                   21 Lagopus muta saturata Salomonsen, 1950
                   22 Lagopus muta capta Peters, 1934
                   23 Lagopus muta hyperborea Sundevall, 1845
                   24 Lagopus muta islandorum (Faber, 1822)