Jinguofortisidae is an extinct family of early

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 ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

s known 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 ...

. They were found in

northern China Northern China () and Southern China () are two approximate regions that display certain differences in terms of their geography, demographics, economy, and culture. Extent The Qinling, Qinling–Daba Mountains serve as the transition zone ...

Description

The Jinguofortisidae are distinguished from other non- ornithothoracine

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 by the following features: the

scapula The scapula (: scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either side ...

and

coracoid A coracoid is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is present as part of the scapula, but this is n ...

fused into a

scapulocoracoid The scapulocoracoid is the unit of the pectoral girdle that contains the coracoid and scapula. The coracoid itself is a beak-shaped bone that is commonly found in most vertebrates with a few exceptions. The scapula is commonly known as the ''shoulde ...

; a boomeranged-shaped

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 ...

without a hypocleidium; proximal margin of

humerus The humerus (; : humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius (bone), radius and ulna, and consists of three sections. The humeral upper extrem ...

concave centrally; deltopectoral crest large and not perforated; minor metacarpal markedly bowed caudally; alular digit terminating at the level of the distal end of major metacarpal; and proximal phalanx of the major digit longer than the intermediate phalanx.

Phylogeny

Wang et al. (2018) erected Jinguofortisidae after finding ''

Chongmingia ''Chongmingia'' is a genus of basal Avialae, avialan belonging to Pygostylia that lived during the Aptian. It was found in the Jiufotang Formation in Chaoyang, Liaoning, Chaoyang, China, and was described by Wang ''et al''., 2016. The name comes ...

'' (previously considered Avebrevicauda ''incertae sedis'' by Wang et al. 2016) to be sister to their new taxon ''Jinguofortis''. In 2023, a third jinguofortisid was described by Li ''et al''. They recovered their new taxon, '' Cratonavis'', 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=Q60790769 Bird families Early Cretaceous birds Birds of Asia