Euornithes (from

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

' meaning "true birds") is a natural group which includes the most recent common ancestor of all

avialan Avialae ("bird wings") is a clade containing the only living dinosaurs, the birds, and their closest relatives. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative defi ...

s closer to modern

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

s than to the

enantiornithines The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and cl ...

. This group was defined in the ''

PhyloCode The ''International Code of Phylogenetic Nomenclature'', known as the ''PhyloCode'' for short, is a formal set of rules governing phylogenetic nomenclature. Its current version is specifically designed to regulate the naming of clades, leaving the ...

'' by Juan Benito and colleagues in 2022 as "the largest clade containing ''

Vultur gryphus The Andean condor (''Vultur gryphus'') is a South American New World vulture and is the only member of the genus ''Vultur''. It is found in the Andes mountains and adjacent Pacific coasts of western South America. With a maximum wingspan of and ...

'', but not ''Enantiornis leali'' and ''Cathayornis yandica''".

Description

Clarke ''et al''. (2006) found that the most primitive known euornithians (the Yanornithiformes) had a mosaic of advanced and primitive features. These species retained primitive features like gastralia and a pubic symphysis. They also showed the first fully modern pygostyles, and the type specimen of ''Yixianornis'' (IVPP 13631) preserves eight elongated rectrices (tail feathers) in a modern arrangement. No earlier pygostylians are known which preserve a fan of tail feathers of this sort; instead, they showed only paired plumes or a tuft of short feathers.

Classification

The name Euornithes has been used for a wide variety of avialan groups since it was first named by Leonhard Stejneger in 1884. It was first defined as a clade in 1998 by Paul Sereno, who made it the group of all animals closer to birds than to Enantiornithes (represented by ''Sinornis''). This definition currently includes similar content as another widely used name, Ornithuromorpha, named and defined by Luis Chiappe in 1999 as the common ancestor of ''Patagopteryx'', ''Vorona'', and Ornithurae, plus all of its descendants. Because one definition is node-based and the other branch-based, Ornithuromorpha is a slightly less inclusive group.

Relationships

The cladogram below follows the results of a phylogenetic analysis by Lee ''et al.'', 2014: The following cladogram below follows the results of a phylogenetic analysis by Pei ''et al.'', 2020:

Other genera

The following is a list of primitive euornithian genera and those that cannot be confidently referred to any subgroups, following Holtz (2011) unless otherwise noted.Holtz, Thomas R. Jr. (2012) ''Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,'
Winter 2011 Appendix.
/ref> *†''Alamitornis'' *†''Changmaornis'' *†''Changzuiornis''Huang, J., Wang, X., Hu, Y., Liu, J., Peteya, J. A., & Clarke, J. A. (2016). A new ornithurine from the Early Cretaceous of China sheds light on the evolution of early ecological and cranial diversity in birds. ''PeerJ'', 4: e1765. *†''Dingavis'' *†''Gargantuavis'' *†''Horezmavis'' *†''Iteravis'' *†''Juehuaornis'' *†''Platanavis'' *†''Wyleyia''? *†''Yumenornis'' *''Xinghaiornis'' *†''Zhyraornis'' Note that Holtz also included the genera ''Eurolimnornis'' and ''Piksi'' as euornitheans, though they have since been re-identified as pterosaurs.

References

External links

{{Taxonbar, from=Q2752642 Euornithes, Bird clades