Pterosaur wingtip claw on new Pterodaustro

I’m telling you, they’re everywhere.
Traditional paleontologists report the wing has no ungual on pterosaurs. Here (Fig. 1), yet another wing ungual could be found in a specimen of Pterodaustro (MIC-V263, Codorniú et al. 2013). (Unfortunately that little bone was ignored by Codorniú et al 2013.) Earlier we looked at several other wing ungual examples.

Pterodaustro specimen two wing tips. One clearly shows a wing ungual. The other may also show one, showing its knuckle side.

Figure 1. Click to enlarge. Pterodaustro specimen MIC-V263 two wing tips. The labeled one clearly shows a wing ungual (m4.5, duplicated and rotated in the small box). The other m4.4 (in the large box) does not show an ungual, despite the slight break that matches the other ungual length.  Rather the ungual was lost off the edge of the matrix (see Fig. 2, lower edge). Typically to universally unguals are crushed onto their wider face, showing their essential claw–like character.

I think it’s unusual and atypical that the tip of m4.4, nearest the alleged ungual, is expanded so much. Not sure exactly what’s going on there. Let’s just throw this up as a possibility, despite its apparent clarity. Also unexpected is the texture on the broken portion of m4.4 that makes it look more like a drill bit.

Nice to see someone else is also tracing photographs
I have been vilified for tracing photographs using Adobe Photoshop (computer software). Here, it’s clear that Codorniú et al. (2013) traced the photograph of MIC-V263 (Fig. 2), the first step in DGS, because there is a perfect correspondence between drawing and photo. That doesn’t happen very often otherwise.

Pterodaustro DGS tracing by Codorniú et al. (2013). See, it's not such a bad thing after all.

Figure 2. Click to enlarge. Pterodaustro DGS tracing by Codorniú et al. (2013). There’s a perfect correspondence of elements. See, DGS is not such a bad thing after all. Even though they traced m4.5 (the wing ungual) they did not identify it as such, overlooking its significance.

Interestingly
The gastroliths are all located between the ilia. This must have happened when the crop was shifted posteriorly during taphonomy.

Wing digit 5
I see some probable m4.5 elements (Fig. 3), but they are shifted from their typical orientation.

Figure 4. Pterodaustro possible wing digit 5, rotated medially. Ungual in lavender. Other phalanges in baby blue. Metacarpal in green. Carpal in magenta.

Figure 3. Pterodaustro possible wing digit 5, rotated medially. Ungual in lavender. Other phalanges in baby blue. Metacarpal in green. Carpal in magenta. Looks like all the other examples I have ever found. Worth keeping a lookout for. 

What else?
Pedal digit 5 appears to have one phalanx, but the end of p5.1 is a hinge joint and the next bone is barely visible beneath it.

Manual digit 3 is seen for the first time as longer than m digit 2. This is distinct from Ctenochasma in which the digits 2 and 3 are subequal. Manual 3.2 in Pterodaustro is not a disc. This was corrected in the reconstructions of both the adult (Fig. 4) and embryo. The femur also has a longer neck than I originally thought.

Pterodaustro adult with manual digit 3 repaired.

Figure 4. Pterodaustro adult with manual digit 3 repaired.

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
Codorniú L, Chiappe LM and Cid FD 2013. First occurrence of stomach stones in pterosaurs, Journal of Vertebrate Paleontology, 33:3, 647-654.

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