azhdarchoidea

Azhdarchoidea was named by paleontologist David Unwin in 1995.Unwin, D. M. 1995. Preliminary results of a phylogenetic analysis of the Pterosauria (Diapsida: Archosauria); pp. 69–72 in A. Sun and Y. Wang (eds.), Sixth Symposium on Mesozoic Terrestrial Ecosystems and Biota, Short Papers. China Ocean Press, Beijing. He later gave the clade a phylogenetic definition in 2003. He defined the group as the most recent common ancestor of Quetzalcoatlus and Tapejara, and all its descendants.

Azhdarchoidea is generally considered as one of three major clades of pterodactyloids. The other two major groups are Archaeopterodactyloidea and Pteranodontoidea. In some older classification schemes, azhdarchoids were considered to be closely-related to ctenochasmatoids like Pterodactylus and Ctenochasma. However, most researchers no longer consider this arrangement to be very likely. Instead, azhdarchoids are grouped as close relatives of pteranodontoids under the clade Ornithocheiroidea, which would comprise the bulk of pterodactyloid diversity.

A simplified cladogram illustrating the relationships between azhdarchoids and other pterosaurs based on the analysis of Brian Andres, James Clark, and Xu Xing in 2014 is shown below.

{{clade

|label1=Monofenestrata

|1={{clade

|1=Darwinoptera

|2={{clade

|1=Anurognathidae

|label2=Pterodactyloidea

|2={{clade

|1={{clade

|1=Archaeopterodactyloidea 70px

|2={{clade

|1=Azhdarchoidea 70px

|2=Pteranodontoidea 70px

}}

}}

}}

}}

}}

}}

File:Kariridraco_by_Júlia_d’Oliveira.jpg]]

Azhdarchoidea is generally believed to be composed of several principle families: Azhdarchidae, Chaoyangopteridae, Tapejaridae, Thalassodromidae, and potentially Dsungaripteridae, although Thalassodromidae of these is considered to be a lineage tapejarids by some researchers. However, the interrelationships of these groups is not confidently understood. The azhdarchids and chaoyangopterids are generally considered to be one another's closest relatives, but the affinities of tapejarids, thalassodromids, and dsungaripterids are controversial.{{cite book |last=Witton |first=M. P. |title=Pterosaurs: Natural History, Evolution, Anatomy |publisher=Princeton University Press |year=2013 |isbn=978-0-691-15061-1 |edition=1st}} Some researchers also consider an additional grouping, Alanqidae, composed of taxa formerly considered azhdarchids.

There are several competing views of azhdarchoid relationships. An early study presented by paleontologist Felipe Pinheiro and colleagues in 2011 considered the tapejarids to be a monophyletic clade including the thalassodromines and the chaoyangopterids (therein called "chaoyangopterines").Pinheiro, F.L., Fortier, D.C., Schultz, C.L., De Andrade, J.A.F.G. and Bantim, R.A.M. (in press). "New information on Tupandactylus imperator, with comments on the relationships of Tapejaridae (Pterosauria)." Acta Palaeontologica Polonica, in press, available online 03 Jan 2011. {{doi|10.4202/app.2010.0057}} Other earlier studies, such as that of paleontologists Darren Naish & David Martill in 2006, and that of Lü Junchang and colleagues in 2008, considered the traditional "tapejarids" to be a paraphyletic grade of primitive azhdarchoids, with true tapejarids more basal, and the thalassodromines (alternatively called thalassodromids) and chaoyangopterids being successively more closely related to azhdarchids.{{cite journal |last1=Martill |first1=D. M. |last2=Naish |first2=D. |title=Cranial crest development in the Azhdarchoid pterosaur Tupuxuara, with a review of the genus and tapejarid monophyly |journal=Palaeontology |date=2006 |volume=49 |issue=4 |pages=925–941 |doi=10.1111/j.1475-4983.2006.00575.x|s2cid=15609202 |doi-access=free |bibcode=2006Palgy..49..925M }}{{cite journal | last1 = Lü | first1 = J. | last2 = Unwin | first2 = D.M. | last3 = Xu | first3 = L. | last4 = Zhang | first4 = X. | year = 2008 | title = A new azhdarchoid pterosaur from the Lower Cretaceous of China and its implications for pterosaur phylogeny and evolution | journal = Naturwissenschaften | volume = 95 | issue = 9| pages = 891–897 | doi = 10.1007/s00114-008-0397-5 | pmid = 18509616 | bibcode = 2008NW.....95..891L | s2cid = 13458087 }}

{{multiple image

| direction = vertical

| width = 220px

| align = right

| image1 = Hatzegopteryx.png

| image3 = Arambourgiania philadelphiae.png

| caption3 = Life reconstructions of Hatzegopteryx (top) and Arambourgiania (bottom), giant members of the family Azhdarchidae

}}

Generally speaking, in the modern scientific literature, there are two major competing hypotheses regarding the classification of azhdarchoids. The first of these is based on the work of Brian Andres and colleagues, who have published multiple papers on the taxa Kryptodrakon, Elanodactylus, and Quetzalcoatlus among others, in which they examined the phylogenetic relationships of these groups.{{cite journal |doi=10.1111/j.1475-4983.2008.00761.x |title=A New Pterosaur from the Liaoning Province of China, the Phylogeny of the Pterodactyloidea, and Convergence in Their Cervical Vertebrae |date=2008 |last1=Andres |first1=Brian |last2=Qiang |first2=JI |journal=Palaeontology |volume=51 |issue=2 |pages=453–469 |bibcode=2008Palgy..51..453A |url=http://doc.rero.ch/record/16204/files/PAL_E3412.pdf }} Andres and colleagues have generally suggested that Dsungaripteridae and Thalassodromidae are closely related and that they form a clade (Dsungaripteromorpha) which is more closely related to Azhdarchidae than Tapejaridae.{{Cite journal | doi = 10.1016/j.cub.2014.03.030| title = The Earliest Pterodactyloid and the Origin of the Group| journal = Current Biology| year = 2014| last1 = Andres | first1 = B. | last2 = Clark | first2 = J. | last3 = Xu | first3 = X. | pmid=24768054 | volume=24 | issue = 9| pages=1011–6| doi-access = free | bibcode = 2014CBio...24.1011A}} This result has been corroborated by some other authors.{{cite journal |doi=10.1371/journal.pbio.2001663|doi-access=free |title=Late Maastrichtian pterosaurs from North Africa and mass extinction of Pterosauria at the Cretaceous-Paleogene boundary |date=2018 |last1=Longrich |first1=Nicholas R. |last2=Martill |first2=David M. |last3=Andres |first3=Brian |journal=PLOS Biology |volume=16 |issue=3 |pages=e2001663 |pmid=29534059 |pmc=5849296 }} A simplified version of Andres and colleagues' phylogeny is shown below.

{{clade|style=font-size:80%; line-height:80%;

|label1=Ornithocheiroidea

|1={{clade

|1=Pteranodontoidea

|label2=Azhdarchoidea

|2={{clade

|1=Tapejaridae

|label2=Neoazhdarchia

|2={{clade

|label1=Dsungaripteromorpha

|1={{clade

|1=Microtuban

|2={{clade

|1=Dsungaripteridae

|2=Thalassodromidae

}}

}}

|label2=Neopterodactyloidea

|2={{clade

|1=Chaoyangopteridae

|label2=Azhdarchiformes

|2={{clade

|1=Radiodactylus

|2={{clade

|1=Montanazhdarcho

|2=Azhdarchidae

}}

}}

}}

}}

}}

}}

}}

File:Jiufotang_tapejarids.pngs, one of the prominent azhdarchoid families. Sinopterus (left) and Huaxiadraco (right) are pictured]]

The second hypothesis of azhdarchoid relationships is that Dsungaripteridae is the sister taxon of Azhdarchoidea within the larger clade Tapejaroidea. This hypothesis has been published on by Rodrigo Pêgas and colleagues in their extensive studies of pterosaurs like Sinopterus, Thalassodromeus, and Aerotitan.{{cite journal |doi=10.1080/02724634.2018.1443273 |title=New Information on the osteology and a taxonomic revision of the genus Thalassodromeus (Pterodactyloidea, Tapejaridae, Thalassodrominae) |date=2018 |last1=Pêgas |first1=Rodrigo V. |last2=Costa |first2=Fabiana R. |last3=Kellner |first3=Alexander W. A. |journal=Journal of Vertebrate Paleontology |volume=38 |issue=2 |pages=e1443273 |bibcode=2018JVPal..38E3273P }}{{cite journal |doi=10.7717/peerj.14829|doi-access=free |title=A taxonomic revision of the Sinopterus complex (Pterosauria, Tapejaridae) from the Early Cretaceous Jehol Biota, with the new genus Huaxiadraco |date=2023 |last1=Pêgas |first1=Rodrigo V. |last2=Zhou |first2=Xuanyu |last3=Jin |first3=Xingsheng |last4=Wang |first4=Kai |last5=Ma |first5=Waisum |journal=PeerJ |volume=11 |pages=e14829 |pmid=36788812 |pmc=9922500 }}{{cite journal |doi=10.1080/08912963.2024.2355664 |title=A taxonomic note on the tapejarid pterosaurs from the Pterosaur Graveyard site (Caiuá Group, ?Early Cretaceous of Southern Brazil): Evidence for the presence of two species |date=2024 |last1=Pêgas |first1=Rodrigo V. |journal=Historical Biology |pages=1–22 }} This hypothesis has also received support from other authors. A simplified version of their phylogeny is shown below.

{{clade|style=font-size:80%; line-height:80%;

|label1=Ornithocheiroidea

|1={{clade

|1=Pteranodontoidea

|label2=Tapejaroidea

|2={{clade

|1=Dsungaripteridae

|label2=Azhdarchoidea

|2={{clade

|label1=Tapejaromorpha

|1={{clade

|1=Thalassodromidae

|label2=Tapejariformes

|2={{clade

|1=Caupedactylia

|2=Tapejaridae

}} }}

|label2=Azhdarchomorpha

|2={{clade

|1=Keresdrakon

|2={{clade

|1=Chaoyangopteridae

|label2=Azhdarchiformes

|2={{clade

|1=Alanqidae

|2=Azhdarchidae }} }} }} }}}} }} }}

A wide variety of subclades have been defined within Azhdarchoidea in the last 15 years. Many of these have contradictory or overlapping definitions, and so whether or not these clades represent true monophyletic groups remains hotly debated. Some of the uncertainty regards the position of Thalassodromidae, which may be closely related to either Tapejaridae or Dsungaripteridae. Another source of uncertainty is the affinities of the dsungaripterids themselves. This problematic group has been found to be closely related to Ornithocheiromorpha,Vidovic, S.U. and Martill, D.M. (2017). The taxonomy and phylogeny of Diopecephalus kochi (Wagner, 1837) and "Germanodactylus rhamphastinus" (Wagner, 1851). In Hone, D. W. E., Witton, M. P. &Martill, D. M. (eds) New Perspectives on Pterosaur Palaeobiology. Geological Society, London, Special Publications, 455 {{doi|10.1144/SP455.12}} just outside of Azhdarchoidea,{{Cite journal|last1=Kellner|first1=Alexander W. A.|last2=Weinschütz|first2=Luiz C.|last3=Holgado|first3=Borja|last4=Bantim|first4=Renan A. M.|last5=Sayão|first5=Juliana M.|date=August 19, 2019|title=A new toothless pterosaur (Pterodactyloidea) from Southern Brazil with insights into the paleoecology of a Cretaceous desert|journal=Anais da Academia Brasileira de Ciências|language=en|volume=91|issue=suppl 2|pages=e20190768|doi=10.1590/0001-3765201920190768|pmid=31432888|issn=0001-3765|doi-access=free}}{{cite journal |last1=Kellner |first1=Alexander W. A. |last2=Caldwell |first2=Michael W. |last3=Holgado |first3=Borja |last4=Vecchia |first4=Fabio M. Dalla |last5=Nohra |first5=Roy |last6=Sayão |first6=Juliana M. |last7=Currie |first7=Philip J. |title=First complete pterosaur from the Afro-Arabian continent: insight into pterodactyloid diversity |journal=Scientific Reports |date=2019 |volume=9 |issue=1 |page=17875 |doi=10.1038/s41598-019-54042-z|pmid=31784545 |pmc=6884559 |bibcode=2019NatSR...917875K |doi-access=free }}Borja Holgado, Rodrigo V. Pêgas, José Ignacio Canudo, Josep Fortuny, Taissa Rodrigues, Julio Company & Alexander W.A. Kellner, 2019, "On a new crested pterodactyloid from the Early Cretaceous of the Iberian Peninsula and the radiation of the clade Anhangueria", Scientific Reports 9: 4940 {{doi|10.1038/s41598-019-41280-4}}{{Cite journal|last1=Jiang|first1=Shun-Xing|last2=Zhang|first2=Xin-Jun|last3=Cheng|first3=Xin|last4=Wang|first4=Xiao-Lin|year=2020|title=A new pteranodontoid pterosaur forelimb from the upper Yixian Formation, with a revision of Yixianopterus jingangshanensis|journal=Vertebrata PalAsiatica|url=http://www.ivpp.cas.cn/cbw/gjzdwxb/pressonline/202011/P020210203354269995268.pdf|doi=10.19615/j.cnki.1000-3118.201124}} or within Azhdarchoidea.{{cite journal |doi=10.4202/app.00848.2020 |title=A new pterosaur species from the Lower Cretaceous of Brazil and the paleobiogeography of the Tapejaridae (Azhdarchoidea) |date=2021 |last1=Cerqueira |first1=Gabriela |last2=Santos |first2=Mateus |last3=Marks |first3=Maikon |last4=Sayão |first4=Juliana |last5=Pinheiro |first5=Felipe |journal=Acta Palaeontologica Polonica |volume=66 |doi-access=free }}

• List of pterosaur genera
• Timeline of pterosaur research

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{{Pterosauria|Az.}}

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Category:Tithonian first appearances

Category:Maastrichtian extinctions