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
       01 Order Gaviiformes Wetmore & Miller, 1926
      Count: [†g] 1f;1g; †2f;5g
       02 Order Podicipediformes Fürbringer, 1888
      Count: [†g] 1f;1g; †1f;3g
       03 Order Sphenisciformes Sharpe, 1891
      Count: [†g] 1f; †21g
       04 Order Procellariiformes Fürbringer, 1888
      Count: [†g] 4f;3g; †4g
       05 Order Pelecaniformes Sharpe, 1891
      Count: [†g] 6f;5g; †6f;19g
       06 Order Ardeiformes Wagler, 1830
      Count: [†g] 7f;13g; †6f;31g