''Jidapterus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

chaoyangopterid Chaoyangopteridae (or chaoyangopterids) is a family of pterosaurs within the larger group Azhdarchoidea. Chaoyangopterids lived mostly during the Early Cretaceous period, though possible members, ''Microtuban'', ''Xericeps'' and ''Argentinadraco'' ...

pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the Order (biology), order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cre ...

from the

Aptian The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous Epoch or Series and encompasses the time from 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ag ...

-age

Lower Cretaceous Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Gloucestershire, England See also *Nizhny Nizhny (russian: Ни́жний; masculine), Nizhnyaya (; feminine), or Nizhneye (russian: Ни́� ...

Jiufotang Formation The Jiufotang Formation ( Chinese: 九佛堂组, pinyin: ''jiǔfótáng zǔ'') is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms (see ...

of Chaoyang, Liaoning, China. The genus was in 2003 named by

Dong Zhiming Dong Zhiming ( Chinese: 董枝明, Pinyin: ''Dǒng Zhimíng''; born January 1937) is a Chinese vertebrate paleontologist formerly employed at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing. He began working at th ...

Sun Yue-Wu The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared rad ...

and

Wu Shao-Yuan Wu may refer to: States and regions on modern China's territory * Wu (state) (; och, *, italic=yes, links=no), a kingdom during the Spring and Autumn Period 771–476 BCE ** Suzhou or Wu (), its eponymous capital ** Wu County (), a former county ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

is ''Jidapterus edentus''. The genus name is derived from ''Jílín Dàxué'' or "Jilin University" and a Latinized Greek ''pteron'', "wing". The specific name means "toothless" in

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

Description

''Jidapterus'' is based on

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

CAD-01, a nearly complete skeleton with partial skull. The skull is toothless and relatively long, with a straight and very pointed beak, and a large hole where the

antorbital fenestra An antorbital fenestra (plural: fenestrae) is an opening in the skull that is in front of the eye sockets. This skull character is largely associated with archosauriforms, first appearing during the Triassic Period. Among extant archosaurs, birds ...

is joined with the

nostril A nostril (or naris , plural ''nares'' ) is either of the two orifices of the nose. They enable the entry and exit of air and other gasses through the nasal cavities. In birds and mammals, they contain branched bones or cartilages called t ...

s. The eye sockets are small, and there is no crest along the lower jaw as seen in ornithocheiroids, although a short projection was present at the back of the skull. The

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the other wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingspan ...

of this individual was estimated to be .

Classification

The classification of ''Jidapterus'' has been unstable; the original authors did not assign it to a group. Some of the original authors later suggested it was a more basal azhdarchoid, whereas another group suggested it was closer to ''

Pteranodon ''Pteranodon'' (); from Ancient Greek (''pteron'', "wing") and (''anodon'', "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with ''P. longiceps'' having a wingspan of . They lived during the late C ...

'' and possibly the same genus as '' Chaoyangopterus''. David Unwin assigned it to

Tapejaridae Tapejaridae (from a Tupi word meaning "the old being") are a family of pterodactyloid pterosaurs from the Cretaceous period. Members are currently known from Brazil, England, Hungary, Morocco, Spain, the United States, and China. The most prim ...

without comment in ''The Pterosaurs: From Deep Time'',Unwin, D.M. (2006). ''The Pterosaurs: From Deep Time''. Pi Press:New York, p. 273. . but later, in a collaboration with Lü, agreed that it belonged to another azhdarchoid group and was a close relative of ''Chaoyangopterus'', placing both in the new family

Chaoyangopteridae Chaoyangopteridae (or chaoyangopterids) is a family of pterosaurs within the larger group Azhdarchoidea. Chaoyangopterids lived mostly during the Early Cretaceous period, though possible members, '' Microtuban'', '' Xericeps'' and ''Argentinadraco ...

.Lü, J., Unwin, D.M., Xu, L., and Zhang, X. (2008). "A new azhdarchoid pterosaur from the Lower Cretaceous of China and its implications for pterosaur phylogeny and evolution." ''Naturwissenschaften'' A redescription of the genus in 2017 corroborated these results, and also presented evidence distinguishing it from ''Chaoyangopterus''. Below are two

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

s showing the phylogenetic placement of ''Jidapterus'' within the

Azhdarchoidea Azhdarchoidea (or azhdarchoids) is a group of pterosaurs within the suborder Pterodactyloidea, more specifically within the group Ornithocheiroidea. Pterosaurs belonging to this group lived throughout the Early and Late Cretaceous periods, with ...

. The one on the left is a topology by Felipe Pinheiro and colleagues in 2011. In their phylogenetic analysis, they recovered ''Jidapterus'' within the family

, more specifically within a subfamily called Chaoyangopterinae, sister taxon to both ''Chaoyangopterus'' and '' Shenzhoupterus''. The cladogram on the right is a different topology, recovered by

Alexander Kellner Alexander Wilhelm Armin Kellner (born September 26, 1961) is a Brazilian geologist and paleontologist who is a leading expert in the field of studying pterosaurs. His research has focused mainly on fossil reptiles from the Cretaceous Period, i ...

and colleagues in 2019. Unlike the analysis by Pinheiro and colleagues, the analysis by Kellner and colleagues did not recover ''Jidapterus'' as a tapejarid, but instead recovered it within the family Chaoyangopteridae, still the sister taxon to both ''Chaoyangopteridae'' and ''Shenzhoupterus'', though. Chaoyangopteridae was in turn found as the sister taxon of the family

Azhdarchidae Azhdarchidae (from the Persian word , , a dragon-like creature in Persian mythology) is a family of pterosaurs known primarily from the Late Cretaceous Period, though an isolated vertebra apparently from an azhdarchid is known from the Early Cre ...

, both within the clade Azhdarchoidea. Topology 1: Pinheiro and colleagues (2011). Topology 2: Kellner and colleagues (2019).

References

External links

''Jidapterus''
in The Pterosauria {{Taxonbar, from=Q1014502 Chaoyangopterids Early Cretaceous pterosaurs of Asia Taxa named by Dong Zhiming Fossil taxa described in 2003