''Chongmingia'' is a genus of basal

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 ...

belonging to

Pygostylia Pygostylia is a group of avialans which includes the Confuciusornithidae and all of the more advanced species, the Ornithothoraces. Definition The group Pygostylia was intended to encompass all avialans with a short, stubby tail, as opposed t ...

that lived during the

Aptian The Aptian is an age (geology), age in the geologic timescale or a stage (stratigraphy), stage in the stratigraphic column. It is a subdivision of the Early Cretaceous, Early or Lower Cretaceous epoch (geology), Epoch or series (stratigraphy), S ...

. It was found in the

Jiufotang Formation The Jiufotang Formation () is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms (see Jehol Biota). It is a member of the Jehol group. T ...

in Chaoyang,

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

, and was described by Wang ''et al''., 2016. The name comes from the word ''Chongming'', referring to a Chinese mythological bird, and the specific epithet is in honor of Mr. Xiaoting Zheng.

Taxonomy

The species was first described in 2015; the description appeared in the pages of ''Scientific Reports''. Only the holotype, extracted from the

Jehol Biota The Jehol Biota includes all the living organisms – the ecosystem – of northeastern China between 133 and 120 million years ago. This is the Lower Cretaceous ecosystem which left fossils in the Yixian Formation and Jiufotang Formation. These d ...

sediments from the

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

period in north-east

, was discovered. ''Chongmingia zhengi'' represents a developmental line unknown at the time of description, it illustrates the diversity of traits in contemporary birds. The ''

furcula The (Latin for "little fork"; : furculae) or wishbone is a forked bone found in most birds and some species of non-avian dinosaurs, and is either an interclavicle or formed by the fusion of the two clavicles. In birds, its primary function is ...

'' in ''C. zhengi'' was stiff, which indicates their poor performance and the need to use more force on the fly. On the other hand, the relatively long forelimb and well-developed chest and shoulder

keel The keel is the bottom-most longitudinal structural element of a watercraft, important for stability. On some sailboats, it may have a fluid dynamics, hydrodynamic and counterbalancing purpose as well. The keel laying, laying of the keel is often ...

on the humerus may indicate that the bird was able to provide enough strength to rise into the air. The presence of

gastrolith A gastrolith, also called a stomach stone or gizzard stone, is a rock held inside a gastrointestinal tract. Gastroliths in some species are retained in the muscular gizzard and used to grind food in animals lacking suitable grinding teeth. In ...

s indicates the prevalence of herbivory in early birds. Depending on the point of view, ''C. zhengi'' represents a previously unknown sister taxa to the

Ornithothoraces Ornithothoraces is a group of avialan dinosaurs that includes all enantiornithes ("opposite birds") and the euornithes ("true birds"), which includes modern birds and their closest ancestors. The name Ornithothoraces means "bird thoraxes". This r ...

clade, belonging to

Avialae 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 Deinonychosauria, deinonychosaurs, though ...

, or a sister taxon to a clade made up of all other

except ''

Archaeopteryx ''Archaeopteryx'' (; ), sometimes referred to by its German name, "" ( ''Primeval Bird'') is a genus of bird-like dinosaurs. The name derives from the ancient Greek (''archaîos''), meaning "ancient", and (''ptéryx''), meaning "feather" ...

''. The creators of the genus proposed two possible cladograms depicting kinship between ''C. zhengi'' and related taxa. The proposal that the new genus is a sister group for a clade made up of all the other avialans except ''

'' is marked in green, while the competitive hypothesis for the

sister group in its shown in blue. In the 2018 description of the basal pygostylian ''

Jinguofortis ''Jinguofortis'' is a genus of primitive avialan belonging to the clade Pygostylia that lived during the Valanginian stage of the Early Cretaceous. It was found in the Dabeigou Formation in northeastern China, and isotope dating from the samples ...

'', ''Chongmingia'' was recovered as a basal pygostylian sister to the former genus, and both genera placed in the new family

Jinguofortisidae Jinguofortisidae is an extinct family of early pygostylian dinosaurs known from the Early Cretaceous. They were found in northern China. Description The Jinguofortisidae are distinguished from other non- ornithothoracine avialans by the followin ...

.Min Wang; Thomas A. Stidham; Zhonghe Zhou (2018). "A new clade of basal Early Cretaceous pygostylian birds and developmental plasticity of the avian shoulder girdle". Proceedings of the National Academy of Sciences of the United States of America. in press. . In 2023, a third jinguofortisid was described by Li ''et al''. They recovered their new taxon, ''

Cratonavis ''Cratonavis'' (meaning "Craton bird") is an extinct genus of pygostylian avialian from the Early Cretaceous Jiufotang Formation of Liaoning Province, China. The genus contains a single species, ''C. zhui'', known from a complete skeleton. D ...

'', as the

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

to ''Chongmingia''. The results of their

phylogenetic analyses In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as Computational phylogenetics, phylogenetic inference. It infers the relationship among organ ...

are shown in the

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

below.

References

{{Taxonbar, from=Q25407152 Jinguofortisidae Bird genera Aptian birds Jiufotang Formation Fossil taxa described in 2016 Birds of Asia