Tapejara navigans skull

Another short post with a nice picture attached, but hey, it is of a fantastic pterosaur. This is the great T. navigens first described as recently as 2003 though it has slipped into the mainstream conciousness of dinosaur research with the other Tapejara species (I should point out here that the actual taxonomy of Tapejara is in a state of flux at the moment, but will probably be sorted out soon with several species getting new generic assignments).

IMGP2204Anywhere, here is the skull (and indeed the whole thing as this is all we have). I have shown a close up of this before to show off the detail of how the skull bones fuse and run into the soft tissues on the upper part but this is the whole thing. As you can see the top is missing and the lower jaw is done, so it’s more ‘most of a skull’ than a skull, but the preservation is very good and when you get in close there’s tons of information there and parts are well preserved in 3-D. I’ve some photos of Ludodactylus I must dig out at some point for the site. Dino Frey at the Karlsruhe museum of natural history is kind enough to let me use my photos of stuff in their collections on my blog which is great for pterosaur fans as they have so many great pieces.

13 Responses to “Tapejara navigans skull”

  1. 1 Matt Martyniuk 30/05/2009 at 1:31 pm

    Something I’ve wondered about for a while–you mentioned in the last post that tapejarids have fibers stiffening the lower soft tissue but not upper, but also show the tissue grading smoothly into the bone. Is the soft tissue more akin to skin (many _T. imperator_ illustrations seem to show skin stretched between the bony struts, almost like the wing membrane) or keratin, or something in between? If it’s “grading” into the bone you’d think it would be keratin or cartilage, but the fiber and non-fiber bit sounds more like something strengthening a skin membrane like actinofibrils… is it possible to tell from fossils like _T. navigans_ what kind of soft tissue we’re dealing with?

  2. 2 David Hone 30/05/2009 at 4:07 pm

    Hi Matt, you have me a bit confused here with the “fibers stiffening the lower soft tissue but not upper”. There is a bony lower part and a soft-tissue upper part. There is no lower soft tissue (are you sure I wrote that?). The bone does grade into the soft tissue (i.e. there is a fairly smooth transition from one to the other as the amount of bone decreases and soft tissue takes over (the soft tissue indeed having stiffening fibers), though as you can see there are kinds of struts etc. of bone running into the soft tissue part. As for the actual kind of tissue I don’t know, nor do I think has anyone really had even an educated guess in the literature. It must be semi-rigid to a degree or it would just flop around and get in the way, but after that I really don’t know. It doesn’t fossilise like cartilage or keratin so those are probably out but it get’s tricky after that.

  3. 3 David Hone 30/05/2009 at 4:09 pm

    Hmmmm just realised you may have meant the fact that the soft tissue continues to the point where there do not appear to be fibers supporting it (at least it’s possible) by the ‘upper and lower’ part, and not two different crests. Sorry. The answer above should still be more or less right though.

  4. 4 Felipe Pinheiro 30/05/2009 at 4:39 pm

    Wow. That’s, for sure, a wonderful specimen. But I really can’t see great differences between T. navigans and Tupandactylus (Tapejara) imperator. It would help a lot if the occipital region was preserved in this specimen (the holotype seems more complete, but the photographs and drawings don’t show if the specimen really lacks an occipital extension of the sagital crest or if it’s just broken). Can T. navigans represent a distinct ontogenetic stage of T. imperator?

  5. 5 David Hone 30/05/2009 at 6:45 pm

    The original description deals with this and while navigans is not a full adult it is also much smaller than imperator. Compared to imperator it lacks a posterior spine (and in fact this is only half the skull, it’s split into two plates, together it’s really quite complete) and had a more poterirorly inclined anterior bar. Frey et al. say that they do not think it could be part of an ontogenetic sequence (and I’d agree) as the angle of the anterior part probably wouldn’t change. Also our knowledge of pterosaurs (and dinosaurs) with ontogentic changes suggests that these kinds of characters only appear late in ontogeny, so there would have to be quite a few changes occur *very* late on to make a navigans look like an imperator. Both need fuller descriptions, but I think pretty much everyone is happy that they are different (and indeed now probably different genera, not even different species).

    • 6 Felipe Pinheiro 30/05/2009 at 9:40 pm

      Could it, therefore, be an example of sexual dimorphism?

      • 7 David Hone 31/05/2009 at 12:31 am

        Well possibly, but that’s pretty had to judge on one partial specimen of each. You’d need to look more at the details of the rest of the skulls and neither of them have been descirbed in great detail. It’s possible, but personally I doubt it.

  6. 8 Matt Martyniuk 31/05/2009 at 12:00 am

    Thanks for the response Dave, that does answer my question. I was referring to this post (https://archosaurmusings.wordpress.com/2008/07/18/pterosaur-head-crests/) where you wrote “There are two distinctly different soft tissues present in Tapejara imperator, with the lower part clearly having some form of stiffening fibres, and the upper one without.” I guess you were talking about the ‘serrations’ of bone where the grade begins.

  7. 9 David Hone 31/05/2009 at 12:32 am

    Well I was talking about imperator, not navigans there which may also be part of it Matt and that does have a fairly clear distinction between the base and top part of the soft tissue crest. In navigens there appears to be only a single type of unstiffened (or only partially stiffened) soft tissue crest, hough both show the grading of bone inot soft tissue. Hope tat clears it up.

  8. 10 Felipe Pinheiro 31/05/2009 at 6:01 am

    The nomenclature of these tapejarid beasts is really confusing me. Right now, I couldn’t say if it’s more correct to call this particular species Tapejara navigans, Tupandactylus navigans or Ingridia navigans!

  9. 11 David Hone 31/05/2009 at 10:25 am

    Well that needs to be sorted out properly, but I believe Alex Kellner published a new tame as Tupanadactylus before Indrigia was formally used and thus the former name is right. I’ve not been keeping up with the taxonomy and there is a big review of this coming which should sort out any remaining issues, or at least lay them out properly.

  10. 12 Christopher Collinson 01/06/2009 at 4:29 am

    I would absolutely love a large hi res image of Ludodactylus!

  11. 13 Felipe Pinheiro 28/01/2011 at 10:03 pm

    We discussed the T. imperator vs T. navigans issue on a recent paper, that is already published online:


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