Wikipedia
Pseudodontornis is a rather disputed genus of the prehistoric pseudotooth birds. The pseudotooth birds or pelagornithids were probably rather close relatives of either pelicans and storks, or of waterfowl, and are here placed in the order Odontopterygiformes to account for this uncertainty. Up to five species are commonly recognized in this genus.
But actually the genus Pseudodontornis is barely more than a nomen nudum. And though it served as the namesake for a popular alternate common name of the pseudotooth birds – "pseudodontorns" or "pseudodontornids" – that was extensively used in the 20th century, current authors prefer "pelagornithids" because this is less fraught with taxonomic dispute. Pelagornis, the type genus of the family Pelagornithidae, was long unrecognized as a pseudotooth bird as it was known mainly from arm bones. Thus, though the Pelagornithidae were long recognized as very distinct, they were allied with the cormorant and gannet in suborder Sulae (or superfamily Sulides in suborder Pelecanae) before it was recognized that they are actually pseudotooth birds. The presumed family "Pelagornithidae", deemed invalid nowadays, had been recognized as pseudotooth birds all along, as they were established based on skull fossils preserving parts of the "toothed" beak.
One of the species typically placed here – though in fact one that is rather unlikely to actually belong in Pseudodontornis – is the only smallish pseudotooth bird species known with certainty from the Neogene as of 2009. However, the enigmatic Tympanonesiotes was of similar size and may also be of Neogene age.