Phylum Chordata Bateson, 1885 - chordates
   Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
     Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
       Superorder Neognathae Pycraft, 1900 see Cohort Neognathae Pycraft, 1900
         Order Galliformes Temminck, 1820 - fowl
           Family Tetraonidae Vigors, 1825
             Genus Lagopus Brisson, 1760 - ptarmigan
               1 Lagopus lagopus (Linnaeus, 1758) - willow grouse
               2 Lagopus mutus (Montin, 1776) - rock ptarmigan see Lagopus muta (Montin, 1781)
               3 Lagopus leucurus (Richardson, 1831) - white-tailed ptarmigan see Lagopus leucura (Richardson, 1831)