Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
Count: 28o;94f;139g;10s; ‡2o;4f;17g; †3o;34f;315g;10s
   Subclass Ornithurae Haeckel, 1866 see Clade Ornithurae Haeckel 1866 [Gauthier 1986] {Chiappe 1991}
  Count: 28o;94f;139g;10s; ‡2o;4f;17g; †1o;32f;312g;4s
     Infraclass Carinatae Merrem, 1813 see Clade Carinatae Merrem 1813 [Gauthier & de Queiroz 2001]
    Count: 23o;88f;128g; ‡1f;11g; †1o;29f;298g
       Order Pelecaniformes Sharpe, 1891
      Count: [†g] 6f;5g; †6f;19g
         Suborder Fregatae Sharpe see Infraorder Fregatides Sharpe, 1891
        Count: 1f
           1 Family Fregatidae Degland & Gerbe, 1867 - frigatebirds
          Count: -