name = Azhdarchids
image_width = 200px
image_caption = Foraging "Quetzalcoatlus northropi".
phylum = Chordata
classis = Sauropsida
familia = Azhdarchidae
familia_authority = Nessov, 1984
subdivision_ranks = Genera
subdivision = See text
Azhdarchidae (from "Ajdarxo", the name of a dragon in
Uzbekmythology) is a family of pterosaurs known primarily from the late CretaceousPeriod, and which included some of the largest known flying animals of all time. Originally considered a sub-family of Pteranodontidae, Nessov (1984) named the azhdarchinae to include the pterosaurs " Azhdarcho", " Quetzalcoatlus", and "Titanopteryx" (now known as " Arambourgiania"). Azhdarchids are characterized by their long legs and extremely long necks, made up of elongated neck vertebrae which are round in cross section. Most species of azhdarchids are still known mainly from their distinctive neck bones and not much else. The few azhdarchids that are known from reasonably good skeletons include " Zhejiangopterus" and " Quetzalcoatlus". Azhdarchids are also distinguished by their relatively large heads and long, spear-like jaws. It had been suggested azhdarchids were skimmers,Nessov, L. A. (1984). [" [http://www.azhdarcho.com/Art/Paleoart/azhdarch3.htm Upper Cretaceous pterosaurs and birds from Central Asia.] "] "Paleontologicheskii Zhurnal", 1984(1), 47-57.] Kellner, A. W. A., and Langston, W. (1996). "Cranial remains of "Quetzalcoatlus" (Pterosauria, Azhdarchidae) from Late Cretaceous sediments of Big Bend National Park, Texas." "Journal of Vertebrate Paleontology", 16, 222-231.] but further research has cast doubt on this idea, demonstrating that azhdarchids lacked the necessary adaptations for a skim-feeding lifestyle, and that they may have led a more terrestrial existence similar to modern storks.Chatterjee, S., and Templin, R. J. (2004). "Posture, locomotion, and paleoecology of pterosaurs." "Geological Society of America Special Publication", 376, 1-64.] Ősi, A., Weishampel, D.B., and Jianu, C.M. (2005). "First evidence of azhdarchid pterosaurs from the Late Cretaceous of Hungary." "Acta Palaeontologica Polonica", 50(4): 777–787.] Humphries, S., Bonser, R.H.C., Witton, M.P., and Martill, D.M. (2007). " [http://biology.plosjournals.org/archive/1545-7885/5/8/pdf/10.1371_journal.pbio.0050204-L.pdf Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method.] " "PLoS Biology", 5(8): e204.]
Azhdarchids were originally classified as close relatives of "
Pteranodon" due to their long, toothless beaks. Others have suggested they were more closely related to the toothy Ctenochasmatids (which include filter-feeders like " Ctenochasma" and " Pterodaustro"). Currently it is widely agreed that azhdarchids were closely related to pterosaurs such as " Tupuxuara" and "Tapejara".
Classification after Unwin 2006, except where noted.cite book |last=Unwin |first=David M. |title=The Pterosaurs: From Deep Time |year=2006 |publisher=Pi Press |location=New York |isbn=ISBN 0-13-146308-X |pages=273]
* Family Azhdarchidae
Aralazhdarcho"Averianov, A.O. (2007). "New records of azhdarchids (Pterosauria, Azhdarchidae) from the late Cretaceous of Russia, Kazakhstan, and Central Asia." "Paleontological Journal", 41(2): 189-197.]
** Possible valid azhdarchid genera
*** "Ornithocheirus" "bunzeli"
* Astibia, H., Buffetaut, E., Buscalioni, A.D., Cappetta, H., Corrall, C., Estes, R., Garcia-Garmilla, F., Jaeger, J.J., Jimenez-Fuentes, E., Loeuff, J. Le, Mazin, J.M., Orue-Etxebarria, X., Pereda-Suberbiola, J., Powell, J.E., Rage, J.C., Rodriguez-Lazaro, J., Sanz, J.L., and Tong, H. (1991). "The fossil vertebrates from Lafio (Basque Country, Spain); new evidence on the composition and affinities of the Late Cretaceous continental fauna of Europe." "Terra Nova", 2: 460-466.
* Bennett, S. C. (2000). "Pterosaur flight: the role of actinofibrils in wing function." "Historical Biology", 14: 255-284.
* Nessov, L.A. (1990). ["Flying reptiles of the Jurassic and Cretaceous of the USSR and the significance of their remains for the reconstruction of palaeogeographic conditions."] "Bulletin of Leningrad University, Series 7, Geology and Geography", 4(28): 3-10 [In Russian] .
* Nessov, L.A. (1991). ["Giant flying reptiles of the family Azhdarchidae: 11. Environment, sedirnentological conditions and preservation of remains."] "Bulletin of Leningrad Universitv Series 7, Geology and Geography", 3(21), 16-24 [In Russian] .
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