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leaf or wing?

This is on behalf of David Peters Silvio Renesto

Chris Bennett wrote:

>> Lastly, I'm no paleobotanist, but isn't the thing that is described
as "Tip
of wing showing aktinofibrils" in Fig. 17 and also visible in Figs. 1
and 2
a leaf?  I do not see any evidence of wing phalanges on either margin.
striations which are presumably interpreted as actinofibrils in Fig. 17
not arranged in the pattern seen in the Zittel wing and other undoubted
pterosaur wings, where they extend obliquely in a posterolateral
from the wing finger, but rather the striations seems to be the parallel

venation in a leaf.  If this is a leaf, then the details and
of the diamond pattern in Figs. 18 and 19 are suspect.<<

In my scan of the image (don't know which plate, but it represents the entire fossil, not a closeup) I see manual phalanges 4.3 and 4.4 along the right margin. A bulbous joint is at their union. They, together with the other wing phalanges exposed in the same zone can be reconstructed as a wing not unlike that of Dorygnathus in size and proportion. The distal end of the terminal digit is bent medially, as often happens in Rhamphorhynchus. Chris is right, the striations appear to parallel the leading edge of the wing, but at this scale, I would hesitate to refer to them as actinofibrils. Perhaps they represent some sort of taphonomic condition.

If it is indeed a leaf, it's a dead ringer for a pterosaur wing. Reverse

Will suffer the consequences if a closeup fails to confirm.

Share this if you think it is appropriate.

David Peters