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Pterosaur wings and refs

With regard to wing shape in pterosaurs. I have seen direct evidence of 
brachiopatagium attachment to the hind limb, as far as the ankle, in Sordes, 
Rhamphorhynchus, Pterodactylus and what is probably Tapejara. I have also seen 
very good photographs of specimens of Eosipterus (the specimen described by Lü 
2002) and Jeholopterus that also appear to show exactly the same thing. So, the 
same relationship seems to be present in six different pterosaurs representing 
at least four completely distinct major clades. Add to this Hazlehurst's (1991) 
discovery of a good correlation between fore and hind limb length in 
pterosaurs, the general similarity of appendicular morphology across a wide 
range of taxa, including all those with direct evidence of brachiopatagium 
attachment to the hind limbs, and one ends up with a clear, well integrated 
picture of whats going on in pterosaurs vis a vis wings and legs. Note that 
this 'Sordes' model is also completely consistent with, for example, qu!
adrupedal plantigrady - as shown y thousands of pterosaur tracks, and is 
supported by a new study by Matt Wilkinson (Cambridge) showing how effective 
and aerodynamically advantageous wing attachment to the hind limbs was for 
pterosaur flight. Since no one has ever presented any evidence, direct or 
indirect to show that the brachiopatagium was not attached to the hind limb, in 
any pterosaur, it is most parsimonous to assume that the Sordes model, at least 
with respect to the brachiopatagium, applies to all pterosaurs. Reconstructing, 
the exact shape of the brachopatagium, as it was in life, is more problematic 
in that its not clear how extensible it might have been originally. Certainly 
what is evident in fossils should probably be taken as the minimum. 

If you want to read the latest about snappy flappers try these:

A tale of a tail:

Dalla Vecchia, F. M. 2002. A caudal segment of a Late Triassic pterosaur 
(Diapsoda, Pterosauria) from North-Eastern Italy. Atti de Museo Friulano di 
Storia Naturale 23, 31-58. 

Jeholopterus and its relationships:

Dalla Vecchia, F. M. 2002. Observations on the non-pterodactyloid pterosaur 
Jeholopterus ningchengensis from the Early Cretaceous of Northestern China. 
Natura Nascosta 24, 8-27.

Giant pterosaur tracks:

Hwang, Koo-Geun, Huh, M., Lockley, M.G., Unwin, D.M. and Wright, J.L. 2002. New 
pterosaur tracks (Pteraichnidae) from the Late Cretaceous Uhangri Formation, SW 
Korea. Geological Magazine, 139 (4), 421-435.

Cearadactylus: yes, its a gnathosaurine ctenochasmatid ctenochasmatoid. 

Unwin, D. M. 2002 On the systematic relationships of Cearadactylus atrox, an 
enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil. 
Mitteilungen Museum für Naturkunde Berlin, Geowissenschaftlichen Reihe, 5, 

Institut fur Palaontologie, MUSEUM FUR NATURKUNDE 
Zentralinstitut der Humboldt-Universitat zu Berlin
Invalidenstrasse 43, D-10115 Berlin, GERMANY

Email: david.unwin@rz.hu-berlin.de

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