Neornithes Gadow, 1893 - living birds
   Neognathae Pycraft 1900 see Cohort Neognathae Pycraft, 1900
     Neoaves Sibley et al. 1988 see Subcohort Neoaves Sibley et al., 1988
       Ciconiiformes Bonaparte, 1854
         Ardeidae Leach, 1820 - herons, bitterns and egrets
           Botaurinae Bock, 1956
             Ixobrychus Billberg, 1828
               Ixobrychus exilis (Gmelin, 1789) - least bittern
                 Ixobrychus exilis exilis (Gmelin, 1789)