Azhdarchidae

Azhdarchids
Temporal range: Late Cretaceous, 108–66Ma

Possibly earlier

Reconstructed skeleton of Quetzalcoatlus northropi
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Order: †Pterosauria
Clade: †Neoazhdarchia
Family: †Azhdarchidae
Nesov, 1984
Type species
†Azhdarcho lancicollis
Nesov, 1984
Genera

See text

Synonyms

"Titanopterygiidae"
Padian, 1984 (preoccupied)

Azhdarchidae (from اژدرها (Aždarha), the Persian word for dragon) 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 Cretaceous as well (late Berriasian age, about 140Ma ago).[1] Azhdarchids included some of the largest known flying animals of all time. Originally considered a sub-family of Pteranodontidae, Nesov (1984) named the azhdarchinae to include the pterosaurs Azhdarcho, Quetzalcoatlus, and "Titanopteryx" (now known as Arambourgiania). They were the last known surviving members of the pterosaurs, and were a rather successful group with a worldwide distribution. By the time of the end-Cretaceous mass extinction, all the pterosaur families except for the Azhdarchidae were already gone.[2]

Description

Artist's reconstruction of foraging Quetzalcoatlus northropi

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,[3][4] 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 and ground hornbills.[5][6][7][8][9]

Systematics

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.

Taxonomy

Classification after Unwin 2006, except where noted.[10]

Reconstructed feeding posture of an azhdarchid with sagittally aligned limbs.

References

  1. ↑ Dyke, G., Benton, M., Posmosanu, E. and Naish, D. (2010). "Early Cretaceous (Berriasian) birds and pterosaurs from the Cornet bauxite mine, Romania." Palaeontology, published online before print 15 September 2010. doi:10.1111/j.1475-4983.2010.00997.x
  2. ↑ "Toothless 'dragon' pterosaurs dominated the Late Cretaceous skies". ScienceDaily.
  3. ↑ Nesov, L. A. (1984). "Upper Cretaceous pterosaurs and birds from Central Asia.". Paleontologicheskii Zhurnal 1984 (1): 47–57.
  4. ↑ Kellner, A. W. A.; Langston, W. (1996). "Cranial remains of Quetzalcoatlus (Pterosauria, Azhdarchidae) from Late Cretaceous sediments of Big Bend National Park, Texas". Journal of Vertebrate Paleontology 16 (2): 222–231. doi:10.1080/02724634.1996.10011310.
  5. ↑ Chatterjee, S.; Templin, R. J. (2004). "Posture, locomotion, and paleoecology of pterosaurs". Geological Society of America Special Publication 376: 1–64. doi:10.1130/0-8137-2376-0.1.
  6. ↑ Ősi, A.; Weishampel, D.B.; Jianu, C.M. (2005). "First evidence of azhdarchid pterosaurs from the Late Cretaceous of Hungary". Acta Palaeontologica Polonica 50 (4): 777–787.
  7. ↑ Humphries, S.; Bonser, R.H.C.; Witton, M.P.; Martill, D.M. (2007). "Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method" (PDF). PLoS Biology 5 (8): e204. doi:10.1371/journal.pbio.0050204.
  8. ↑ Witton, Mark P.; Naish, Darren; McClain, Craig R. (28 May 2008). "A Reappraisal of Azhdarchid Pterosaur Functional Morphology and Paleoecology". PLoS ONE 3 (5): e2271. doi:10.1371/journal.pone.0002271. PMC 2386974. PMID 18509539.
  9. ↑ "Pterosaurs".
  10. ↑ Unwin, David M. (2006). The Pterosaurs: From Deep Time. New York: Pi Press. p. 273. ISBN 0-13-146308-X.
  11. ↑ Ibrahim, N.; Unwin, D.M.; Martill, D.M.; Baidder, L.; Zouhri, S. (2010). Farke, Andrew Allen, ed. "A New Pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco". PLoS ONE 5 (5): e10875. doi:10.1371/journal.pone.0010875. PMC 2877115. PMID 20520782.
  12. ↑ 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. doi:10.1134/S0031030107020098.
  13. ↑ Andres, B.; Myers, T. S. (2013). "Lone Star Pterosaurs". Earth and Environmental Science Transactions of the Royal Society of Edinburgh: 1. doi:10.1017/S1755691013000303.
  14. ↑ 14.0 14.1 Averianov, A.O. (2010). "The osteology of Azhdarcho lancicollis Nessov, 1984 (Pterosauria, Azhdarchidae) from the Late Cretaceous of Uzbekistan." Proceedings of the Zoological Institute of the Russian Academy of Sciences, 314(3): 246-317.
  15. ↑ Vremir, M. T. S.; Kellner, A. W. A.; Naish, D.; Dyke, G. J. (2013). Viriot, Laurent, ed. "A New Azhdarchid Pterosaur from the Late Cretaceous of the Transylvanian Basin, Romania: Implications for Azhdarchid Diversity and Distribution". PLoS ONE 8: e54268. doi:10.1371/journal.pone.0054268.
  16. ↑ Averianov, A.O.; Arkhangelsky, M.S.; Pervushov, E.M. (2008). "A New Late Cretaceous Azhdarchid (Pterosauria, Azhdarchidae) from the Volga Region". Paleontological Journal 42 (6): 634–642. doi:10.1134/S0031030108060099.