The Pelecaniformes are an order of medium-sized and large waterbirds found worldwide.
The pelicans, shoebill and hamerkop form a clade within the order, with their next closest relatives being a clade containing the herons, ibises and spoonbills.
Pelecaniformes
Threskiornithidae – ibises, spoonbills (36 species)
Ardeidae – herons, bitterns (72 species)
Balaenicipitidae – shoebill
Scopidae – hamerkop
Pelecanidae – pelicans (8 species)