| Pangalliformes | |
|---|---|
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| Malegrey junglefowl,Gallus sonneratii | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Superorder: | Galloanserae |
| Clade: | Pangalliformes Clarke, 2004 |
| Subgroups | |
| Synonyms | |
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Pangalliformes is the scientific name of a provisionalclade of birds within the groupGalloanserae. It is defined as all birds more closely related tochickens than toducks, and includes all modern chickens, turkeys, pheasants, and megapodes, as well as extinct species that do not fall within the crown groupGalliformes.
Galliform-like pangalliformes are represented byextinct families from thePaleogene, namely theGallinuloididae,Paraortygidae andQuercymegapodiidae. In the earlyCenozoic, some additional birds may or may not be early Galliformes, though even if they are, it is rather unlikely that these belong to extant families:
More recently,Sylviornis and its sister taxonMegavitiornis was considered as stem-galliforms,[1] suggesting that at least one lineage of Pangalliformes outside the crown group Galliformes survived to the Holocene.[2] This same study also presentsDromornithidae as possibly closer toGalliformes than toAnseriformes as traditionally expected, though it acknowledges that more work is required for confirmation.[1] A 2024 study alternatively classified dromornithids as crown anseriforms and suggested thatGastornithiformes andsylviornithids are crown-group galliforms.[3]
A few fragmentaryfossils have been described as pangalliforms from theLate Cretaceous.Asteriornis, one of the earliest knownpangalloanserine birds, likely belongs to the pangalliforms.[4]Austinornis lentus (formerly referred to asIchthyornis lentus,Graculavus lentus, orPedioecetes lentus) was found in the Late CretaceousAustin Chalk near Fort McKinney,Texas. In 2004, Clarke classified it within Pangalliformes rather than true Galliformes, pending further fossil finds.[5] However, other researchers have disputed its classification and dismissed it in phylogenetic analyses due to the fragmentary nature of the holotype.[6][7][8] Notably, in 2014, Gerald Mayr suggested thatAustinornis is a non-neornithine from theConiacian orSantonian age and that the specimen probably belongs to theornithurineApatornis orIaceornis.[9]
Another specimen,PVPH 237, from the Late CretaceousPortezuelo Formation (Turonian-Coniacian, about 90 Ma) in theSierra de Portezuelo (Argentina) has also been suggested to be an early relative of true galliformes, though the study did not specifically classified the specimen as a pangalliform. This is a partialcoracoid of a possible neornithine bird, which in its general shape and particularly the wide and deep attachment for the muscle joining the coracoid and thehumerus bone resembles the morebasal lineages of galliforms.[10]
