Gigantornis eaglesomei is a very large prehistoric bird described from a fragmentary specimen from the Eocene of Nigeria.

[3] It is not known whether this bird belongs to a distinct genus; it might even be the very same species as the similar-sized Dasornis emuinus, whose fossils are not uncommon in the Ypresian (Early Eocene) London Clay of the Isle of Sheppey (England).

Remains of a large pseudotooth bird were also found in the Middle Eocene of Kpogamé-Hahotoé (Togo) and have been provisionally[4] termed "Aequornis traversei"; their analysis is likely to provide at least some insight on the taxonomic status of G.

Compared to LHNB (CCCP)-1, a Middle to Late Miocene pseudotooth bird sternum found in Portugal and tentatively assigned to Pelagornis, its articular facet for the furcula consists of a flat section at the very tip of the sternal keel and a similar one set immediately above it at an outward angle, and the spina externa is shaped like an Old French shield in cross-section.

The slightly smaller LHNB (CCCP)-1 has a less sharply protruding sternal keel, the articular facet for the furcula consists of a large knob at the forward margin, and the spina externa is narrow in cross-section.