Rhamphorhynchus Wing Tracings

Padian and Rayner (1993) published several soft tissue specimens of pterosaur wings. Here are several Rhamphorhynchus images along with color tracings to help delineate the elements.

The Zittel wing

Figure 1. The Zittel wing from a species of Rhamphorhynchus. Click to enlarge.

The Zittel wing tip.

Figure 2. The Zittel wing tip. The green element could be a flipped ungual.

Rhamphorhynchus sp. BSP 1938 I 503a, No. 11 in Wellnhofer 1975

Figure 3. Rhamphorhynchus sp. BSP 1938 I 503a, No. 11 in Wellnhofer 1975 with wing membrane preservation. Here the wings are twisted such that the membrane is anterior to the digit. Even so, there is no deep chord aft of the elbows directed toward the ankles. Inserts enlarge wing tips which appear to include unguals.

Rhamphorhynchus YPM-1178

Figure 4. Rhamphorhynchus YPM-1178. A wing tip was restored in plaster. Blue dots are aligned with joints in the wing.

Rhamphorhynchus BSP AS I 772

Figure 5. Rhamphorhynchus BSP AS I 772 in which one wing membrane has been torn distally from the wing finger. There is no increased chord closer to the body. Lighter pink appears to be some sort of shift in the membrane impressing in the matrix before burial.

BSP-1937-I-37-588

Figure 6. BSP-1937-I-37-588. The central portion is restored in plaster. The chord does not appreciably deepen proximally.

The Big Question Is: Did the Wing Membrane Extend to the Ankle?
Several workers (Bennett 2008; Elgin RA, Hone DWE and Frey E. 2011; Unwin DM and Bakhurina NN 1994) reported that pterosaurs had a deep chord wing membrane that extended to the ankles. We discussed this earlier. All purported samples presented by Elgin et al. (2011) were shown to be bogus. Peters (2002) found no clear connection has been made to the ankle in any pterosaur fossil as this further example also demonstrates. There’s also the example of the darkwing Rhamphorhynchus here. There is no gradual or steep deepening of the wing membrane in any of these specimens.

Membrane Shrinkage?
Elgin RA, Hone DWE and Frey E. (2011) considered the BSP 1938 I 503a specimen (Fig. 3) to be an example of “membrane shrinkage” trying to side-step the evidence for a narrow-chord membrane. There is no membrane shrinkage. There is only folding, ripping and mutilating during taphonomy in every sample above. Every example portrays the same wing shape, which is damn strong evidence that no pterosaur wings were attached to the ankle.

If anyone has ANY evidence of deep chord wing membrane, please bring it forward. I’d love to see it.

As always, I encourage readers to see specimens, make observations and come to your own conclusions. Test. Test. And test again.

Evidence and support in the form of nexus, pdf and jpeg files will be sent to all who request additional data.

References
Bennett SC 2008. Morphological evolution of the forelimb of pterosaurs: myology and function. Pp. 127–141 in E. Buffetaut & D.W.E. Hone (eds.), Flugsaurier: pterosaur papers in honour of Peter Wellnhofer. Zitteliana, B28.
Elgin RA, Hone DWE and Frey E. 2011.The extent of the pterosaur flight membrane. Acta Palaeontologica Polonica 56 (1), 2011: 99-111 doi:10.4202/app.2009.0145 online pdf
Padian K and RaynerJV 1993. The wings of pterosaurs. American Journal of Science 239-A, 91–166.
Peters D 2002. A New Model for the Evolution of the Pterosaur Wing—with a twist. Historical Biology 15:277-301.
Unwin DM and Bakhurina NN 1994. Sordes pilosus and the nature of the pterosaur flight apparatus. Nature 371: 62-64.

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