Gallinuloides enters the LRT with crowned cranes, not with megapodes

Complete fossils of the plover-sized crane
Gallinuloides wyomingensis (Eastman 1900; Early Eocene, Green River Formation, 48 mya) were described by Mayr and Weidig 2004 as stem-group galliforms (= chickens, pheasants and kin). Like traditional bird workers, Mayr and Weidig also considered megapodes to be crown group Galliformes.

Mayr and Weidig reported,
“the Early Eocene Gallinuloides wyomingensis Eastman, 1900 is the earliest known unquestionable galliform bird. To date, the taxon was known only from the holotype, a poorly preserved articulated specimen from the Green River Formation in Wyoming, USA.”

Figure 1. Gallinuloides in situ from Mayr and Weidig 2004, Colors added here. Shown at full scale on monitors operating at 72dpi. A rare four phalanges appear on pedal digit 4, as in Balearica.

That hypothesis of interrelationships is not supported
by the large reptile tree (LRT, 2019+ taxa) where megapodes like Megapodius, nest with kiwis, rheas, cassowaries and ostriches, far from pheasants and turkeys.

Figure 2. From Mayr and Weidig 2004, the skull of another specimen of Gallinuloides.

After testing in the LRT Gallinuloides nests
with a much taller extant crane, Balearica (Figs. 3, 4) and a lily-pad walker with long toes, Jacana (Fig. 4), taxa not previously mentioned in Mayr and Weidig. These taxa nest between basalmost birds and the chicken + pheasant clade in the LRT surrounded by many other taxa.

Figure 3. The skull of the crowned crane, Balearica. Compare to Gallinuloides in figure 2.

Balearica regulorum
(= Ardea regulorum, Anthropoides regularum, Bennett 1834; extant; 1m tall, 2m wingspan) is the gray crowned crane, and a traditional member of the Gruidae/Gruiformes. In the LRT Balearica does not nest with the crane, Grus, but with plovers and kildeer (genus: Charadrius (Fig. 4) and shares with them, a short bill. Twin unique bumps appear on the postfrontals. Only four phalanges appear on pedal digit 4, which is as long as pedal digit 3.

Figure 4. Balearica compared to its sister in the LRT, Charadrius, the plover/kildeer.

Note the tall forehead
in Gallinuloides, as in Balearica. These two also share only four phalanges on toe four.

Figure 5. Subset of the LRT focusing on birds. Gallinuloides has been added to the LRT, but this cladogram is a day old. Gallinuloides nests with Balearica (bottom half of the green square).

Mayr and Weidig reported,
“There is a growing consensus, from both molecular and morphological studies, that the Galliformes are the sister taxon of the Anseriformes (waterfowl).”

This hypothesis of interrelationships is not supported by the LRT. Geese do not look like nor share a niche with chickens. Even so, this is widely supported by bird workers.

References
Mayr G. and Weidig I 2004. The Early Eocene bird Gallinuloides wyomingensis—a stem group representative of Galliformes. Acta Palaeontologica Polonica 49 (2): 211–217.

wiki/Gallinuloides
wiki/Balearica
wiki/Jacana

Publicity
https://a-dinosaur-a-day.com/post/179778390540/gallinuloides