The hoatzin (Opisthocomus hoazin)

Anything other than the primary findings of Miller are not to be expected in any case, as by the time of Hoazinoides, essentially all modern bird families are either known or believed to have been present and distinct. Going further back in time, the Late Eocene or Early Oligocene (some 34 million years ago) Filholornis from France has also been considered "proof" of a link between the hoatzin and the gamebirds. The fragmentary fossil Onychopteryx from the Eocene of Argentina[citation needed] and the quite complete but no less enigmatic Early-Middle Eocene (Ypresian-Lutetian, some 48 million years ago) Foro panarium are sometimes used[citation needed] to argue for a hoatzin-cuculiform (including turacos) link. But as demonstrated above, this must be considered highly speculative, if not as badly off the mark as the relationship with Cracidae discussed by Miller.