View source for Biology:Azhdarcho

{{short description|Genus of azhdarchid pterosaur from the Late Cretaceous}}
{{speciesbox
| fossil_range = [[Earth:Turonian|Turonian]], {{fossilrange|92}}
| image = Azhdarcho.jpg
| image_caption = Fragment of a right ulna
| grandparent_authority = Nesov, 1984
| display_parents = 3
| genus = Azhdarcho
| parent_authority = Nesov, 1984
| species = lancicollis
| authority = Nesov, 1984
}}

'''''Azhdarcho''''' {{IPAc-en|ɑː|ʒ|ˈ|d|ɑr|x|oʊ}} is a genus of azhdarchid [[Biology:Pterosaur|pterosaur]] from the late [[Earth:Cretaceous|Cretaceous]] Period of the [[Earth:Bissekty Formation|Bissekty Formation]] (middle [[Earth:Turonian|Turonian]] stage,<ref name=osteology2010>{{cite journal | last1 = Averianov | first1 = A.O. | year = 2010 | title = The osteology of ''Azhdarcho lancicollis'' Nessov, 1984 (Pterosauria, Azhdarchidae) from the Late Cretaceous of Uzbekistan | url = http://www.zin.ru/journals/trudyzin/doc/vol_314_3/TZ_314_3_Averyanov.pdf | journal = Proceedings of the Zoological Institute of the Russian Academy of Sciences | volume = 314 | issue = 3| pages = 246–317 }}</ref> about 92 million years ago) of Uzbekistan, as well as the [[Earth:Zhirkindek Formation|Zhirkindek Formation]] of Kazakhstan. It is known from fragmentary remains including the distinctive, elongated neck vertebrae that characterizes members of the family [[Biology:Azhdarchidae|Azhdarchidae]], a family that includes many giant pterosaurs such as ''[[Biology:Quetzalcoatlus|Quetzalcoatlus]]''. The name ''Azhdarcho'' comes from the [[Social:Persian language|Persian]] word ''azhdar'' ({{lang|fa|اژدر}}), a dragon-like creature in Persian mythology.<ref>{{cite news |url=http://www.latimes.com/science/sciencenow/la-sci-sn-pterosaur-toothless-flying-reptile-dragon-20140819-story.html |title=Toothless 'dragon' pterosaurs once ruled skies worldwide, study says |newspaper=Los Angeles Times |first=Amina |last=Khan |date=August 19, 2014 |access-date=August 26, 2014}}</ref> The [[Biology:Type species|type species]] is ''Azhdarcho lancicollis''. The [[Biology:Specific name (zoology)|specific epithet]] ''lancicollis'' is derived from the [[Social:Latin|Latin]] words ''lancea'' (meaning "lance" or "spear") and ''collum'' ("neck").

==History==
[[File:Azhdarchid pterosaur neck lengths.png|thumb|Neck vertebrae (third from the bottom) compared to those of other Azhdarchids]]
The [[Biology:Fossil|fossil]] remains of ''Azhdarcho'' were recovered in the Kyzyl Kum desert (from the Taykarshinskaya unit of the [[Earth:Bissekty Formation|Bissekty Formation]]) by Lev A. Nesov during expeditions to Central Asia in 1974–1981. The [[Biology:Type|type specimen]], given the catalog number ЦНИГРмузей 1/11915 (TsNIGRmuzey), consists of an anterior neck vertebra. Twelve [[Biology:Paratype|paratype]]s were referred, including several other neck vertebrae, elements from the wing and leg, and pieces of the jaw. These specimens, along with other vertebrate fossils collected during the expeditions, were deposited at the F.N. Chernyshev Central Geologic Exploration Museum in St. Petersburg.<ref name="nesov1984">{{cite journal |last=Nesov |first=L. A. |url=http://www.henteeth.com/nh/azhdarch3.htm |title=Upper Cretaceous pterosaurs and birds from Central Asia |archive-url=https://web.archive.org/web/20120317044258/http://www.henteeth.com/nh/azhdarch3.htm |archive-date=March 17, 2012 |journal=Paleontologicheskii Zhurnal |year=1984 |issue=1 |pages=47–57}}</ref>

In his description of the type specimen of ''Azhdarcho lancicollis'', Nesov noted its distinctive neck vertebrae, which are extremely elongated and round in cross section at mid-length. He pointed out similar characteristics in several other pterosaurs, and used them to erect the new subfamily Azhdarchinae, classified within the family [[Biology:Pteranodontidae|Pteranodontidae]]. Nesov also referred ''Quetzalcoatlus'' and ''[[Biology:Arambourgiania|Arambourgiania]]'' (then known as ''Titanopteryx'') to this subfamily, which was subsequently re-classified as the family [[Biology:Azhdarchidae|Azhdarchidae]]. He also suggested that similar, thin-walled pterosaur bones from the Lance Formation of Wyoming could be assigned to a species of ''Azhdarcho'', using this as evidence of commonalities between the fauna of Late Cretaceous central Asia and western North America. However, subsequent research has not followed this suggestion, and ''A. lancicollis'' is the only currently recognized species of ''Azhdarcho''.<ref name="unwin2006">{{cite book |last=Unwin |first=David M. |title=The Pterosaurs: From Deep Time |year=2006 |publisher=Pi Press |location=New York |isbn=0-13-146308-X |page=273}}</ref>

==Classification==
Below is a [[Biology:Cladogram|cladogram]] showing the phylogenetic placement of ''Azhdarcho'' within the clade Neoazhdarchia, more specifically within the family Azhdarchidae, of which ''Azhdarcho'' is the  [[Biology:Type genus|type genus]]. The cladogram is based on a topology recovered by Brian Andres and Timothy Myers in 2013.<ref name=LoneStarPterosaurs>{{Cite journal | last1 = Andres | first1 = B. | last2 = Myers | first2 = T. S. | doi = 10.1017/S1755691013000303 | title = Lone Star Pterosaurs | journal = Earth and Environmental Science Transactions of the Royal Society of Edinburgh | volume = 103 | issue = 3–4 | page = 1 | year = 2013 | s2cid = 84617119 }}</ref>

{{clade| style=font-size:85%;line-height:85%
|label1=&nbsp;Neoazhdarchia&nbsp;
|1={{clade
            |1={{clade
               |label1=&nbsp;[[Biology:Thalassodrominae|Thalassodrominae]]&nbsp;
               |1={{clade
                  |1=''Thalassodromeus sethi''
                  |2={{clade
                     |1=''Tupuxuara leonardii''
                     |2=''Tupuxuara longicristatus''}} }}
               |label2=&nbsp;[[Biology:Dsungaripteridae|Dsungaripteridae]]&nbsp;
               |2={{clade
                  |1={{clade
                     |1=''Domeykodactylus ceciliae''
                     |2=''Dsungaripterus weii''}}
                  |2={{clade
                     |1=''Noripterus complicidens''
                     |2=''Noripterus parvus''}} }} }}
            |2={{clade
               |label1=&nbsp;[[Biology:Chaoyangopteridae|Chaoyangopteridae]]&nbsp;
               |1={{clade
                  |1=''Eoazhdarcho liaoxiensis''
                  |2={{clade
                     |1=''Shenzhoupterus chaoyangensis''
                     |2={{clade
                        |1=''[[Biology:Chaoyangopterus zhangi|Chaoyangopterus zhangi]]''
                        |2=''[[Biology:Jidapterus edentus|Jidapterus edentus]]''}} }} }}
               |2={{clade
                  |1=''Radiodactylus langstoni''
                  |label2=&nbsp;[[Biology:Azhdarchidae|Azhdarchidae]]&nbsp;
                  |2={{clade
                     |1='''''Azhdarcho lancicollis'''''
                     |2={{clade
                        |1=TMM 42489
                        |2={{clade
                           |1=''[[Biology:Zhejiangopterus linhaiensis|Zhejiangopterus linhaiensis]]''
                           |2={{clade
                              |1=''[[Biology:Arambourgiania philadelphiae|Arambourgiania philadelphiae]]''
                              |2=''[[Biology:Quetzalcoatlus northropi|Quetzalcoatlus northropi]]''
                              |3=''Quetzalcoatlus lawsoni''}} }} }} }} }} }} }} }}

==Paleobiology==
[[File:Azhdarcho pair.png|thumb|Speculative reconstruction of a pair of ''Azhdarcho'' flying over a calm lake in the early morning.|alt=]]
In the original description of ''Azhdarcho'', Nesov noted that because of the way the vertebrae articulated, the pterosaur would have had very limited flexibility in the neck. ''Azhdarcho'' could not rotate its neck at all, though it could flex the neck vertically to a certain degree. Nesov suggested that pterosaurs like ''Azhdarcho'' may have fed in a manner similar to the modern Skimmer, with their long necks allowing them to scoop prey from the water's surface and small depths without needing to dive. However, recent research has shown that skimming requires more energy and anatomical specializations than previously thought, and that large pterosaurs like ''Azhdarcho'' probably were not capable of skimming.<ref>{{Cite journal |last1=Humphries |first1=Stuart |last2=Bonser |first2=Richard H. C. |last3=Witton |first3=Mark P. |last4=Martill |first4=David M. |name-list-style=amp|date=2007 |title=Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method |journal=PLOS Biology |volume=5 |issue=8 |pages=e204 |doi=10.1371/journal.pbio.0050204|pmc=1925135 |pmid=17676976 |doi-access=free }}</ref> The long neck would also have allowed azhdarchids to hunt for food in the water or on the bottom while swimming, or to hunt poorly flying vertebrates in the air, though Nesov also suggested that the animal would have needed stable weather conditions to fly well, and suggested azhdarchid habitats needed to be dominated by even, mild winds.<ref name="nesov1984"/> However studies by Mark Witton points to a different direction suggesting that azhdarchids in general were terrestrial stalkers.<ref name="terrestrialstalkinginazhdarchids">{{cite magazine |last=Naish |first=Darren  |url=https://blogs.scientificamerican.com/tetrapod-zoology/were-azhdarchid-pterosaurs-really-terrestrial-stalkers-the-evidence-says-yes-yes-they-probably-were/ |title=Were azhdarchid pterosaurs really terrestrial stalkers? The evidence says yes, yes they (probably) were | magazine=Scientific American |date=December 15, 2013 | access-date=January 30, 2021 }}</ref>

==See also==
* [[Biology:Timeline of pterosaur research|Timeline of pterosaur research]]

==References==
{{Reflist}}

{{Taxonbar|from=Q2018929}}

[[Category:Turonian life]]
[[Category:Bissekty Formation]]

{{Sourceattribution|Azhdarcho}}