Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
     Infraclass Neoaves Sibley et al., 1988 see Subcohort Neoaves Sibley et al., 1988
       Parvclass Passerae see Superorder Passerimorphae Sibley et al., 1988
         Superorder Passerimorphae Sibley et al., 1988
           Order Passeriformes Linnaeus, 1758
             Suborder Passeri see Suborder Passeres (C. Linnaeus, 1758) C. Linnaeus, 1766
               Parvorder Passerida (C. Linnaeus, 1758) Sibley et al., 1988
                 Superfamily Sylvioidea
                   Family Certhiidae Leach, 1820 - treecreepers
                     Subfamily Polioptilinae see Family Polioptilidae Baird, 1858
                       Genus Polioptila P.L. Sclater, 1855
                         01 Polioptila caerulea (C. Linnaeus, 1766) - blue-gray gnatcatcher
                         02 Polioptila californica Brewster, 1881
                         03 Polioptila melanura Lawrence, 1857 - black-tailed gnatcatcher
                         04 Polioptila lembeyei (Gundlach, 1858)
                         05 Polioptila nigriceps S.F. Baird, 1864 - black-capped gnatcatcher
                         06 Polioptila albiloris Sclater & Salvin, 1860
                         07 Polioptila plumbea (J.F. Gmelin, 1788)
                         08 Polioptila lactea Sharpe, 1885
                         09 Polioptila guianensis Todd, 1920
                         10 Polioptila schistaceigula E. Hartert, 1898
                         11 Polioptila dumicola (Vieillot, 1817)