Archive for the 'Pterosaurs' Category

Flugsaurier 2015: Portsmouth, UK

Way back in 2001 the first real symposium dedicated solely to pterosaurs (rather than a subset of another conference) was convened in Toulouse thanks largely to the organisation of Eric Buffetaut. By all accounts it was a success and spawned the well known and much cited 2003 Evolution and Palaeobiology of Pterosaurs special volume. The event however was something of a one-off, and I don’t think there was any great plans to have another later conference.

At the end of my time in Germany however, I wanted to arrange a conference and with the museum home to some legendary pterosaur specimens and the retiring Peter Wellnhofer, this ultimately led to Flugsaurier 2007 in Munich. Both a celebration of all things pterosaurian and a tribute to Peter’s career, this was attended by nearly 50 people with delegates from North and South America, Asia, Australia and Europe, and later spawned the 2008 Festschrift for Peter. At the meeting it was agreed that this would be an excellent series to continue and so Flugsaurier 2010 in Beijing was immediately announced, and then this was followed by a shift to South America and Rio 2013 collectively covering three of the great centres for pterosaur finds and research. Each meeting has seen a swathe of researchers descend on the host institute and the unveiling of some up to the minute research and important new finds.

Now though, Flugsaurier returns to Europe and will be in Portsmouth in 2015 from August 25th-30th. Dave Martill is the main organiser of this one at his parent university, ably assisted (well, we think so) by a small army of associates. As has become usual for Flugsaurier, the conference will consist of talks and posters about pterosaurs, workshops and round-table discussions, specimen viewings and fieldtrips. It is NOT limited to academics, and we have a good record of artists, non-pterosaur specialists, curators, and the general public attending as delegates as well as early-career researchers like MSc and PhD students presenting their work. As a generally small meeting, it is rather informal and there’s lots of break-outs and discussions between presentations and through the breaks and evenings and much to talk over.

All the major details are on the website for the event here, and the first circular is already out and online here. Do please share these links with the wider academic and social community (we have tried and failed to get e-mails to the DML and VertPal list so if someone could send out the links, that would be wonderful, thanks), there is a group on Facebook, an @Flugsaurier2015 twitter feed and also we’re using the hashtag #flugsaurier2015 to keep people up to date. More information will follow soon, but the basics are up and online and registration will open shortly.

Some of the best interactions and exchanges we have had at previous meetings have come from those who normally only dabble in pterosaurs and are bringing external ideas and methods into the community so while obviously there is a *lot* of winged reptile stuff going round, it’s not just a meeting of the usual pterosaur suspects. Indeed in this case we really hope for a bit more of that at this one as thanks to some cunning timing, the meeting will run just before SVPCA in the neighbouring city of Southampton.

Yes, you can attend two palaeontological conferences in succession! SVPCA, for those that have never been, is a meeting for vertebrate palaeontology and comparative anatomy. Although very UK centric, SVPCA always attracts a number of European delegates and even those from further afield (Matt Wedel and Don Henderson regularly attend for example) but is also a small meeting (generally around 130 people) and as such is an informal and fun community. There’s no parallel sessions and a relaxed and fun atmosphere (last year we had a presentation done in song with guitar backing!) and it also includes a day for preparators and conservators on top of covering everything from fish to hominids over the run time. SVPCA is also a special haven for palaeoart people (Bob Nicholls, Luis Rey, Mark Witton and John Conway are always there, and those with big outreach profiles like Darren Naish and Dougal Dixon also always attend). In short, those who might be considering a major journey from across the ocean for just a few days of pterosaurs and think it a bit much money and commitment, well the opportunity to combine it with SVPCA hopefully makes it a still greater proposition.

The fieldtrips will also be run in such a way as to maximise this too. A pre-conference excursion to the Isle of Wight on August 25th will effectively start Flugsaurier, and then a post-conference weekend field trip to the Jurassic Coast World Heritage Site on August 29th and 30th will be run jointly with SVPCA as a prelude to that meeting.

Hopefully then there’s some excellent scope for friends, colleagues, researchers and interested people from all over the world to take the opportunity to come to the UK and both meetings. Pterosaurs may not be your first or only love, but the integration with SVPCA makes a superb opportunity to combine the two and see two whole vertebrate meetings. Both are relatively cheap, and with an international community heading over for Flugsaurier as well as a European crowd for SVPCA, it will hopefully be both intimate and wide-ranging.

As a quick aside, note that the plan was always for Flugsaurier to be on a cycle of every three years, but we quickly realised that this cycle specifically ran with the huge ICVM and was sucking up some of our potential delegates who naturally did not want to make two big international trips per year on top of the usual SVPCA / SVP trips. So this one comes just two years after Rio, but we should return to the previous cycle after this and hopefully someone will be volunteering to host Flugsaurier 2018.

I do hope to see an excellent turn out for both (apparently we’re running at nearly two dozen registered for Flugsaurier already in just the first few days of putting out the first circular) and that will grow quickly I’m sure. Roll on 2015!

A new German ‘Darwinopterid’ pterosaur

Regular readers of the Pterosaur.net blog will have already seen this post and might well have put two and two together and realised that this is ‘Darwinopterus’-like pterosaur from the Solnhofen. We are still waiting some kind of proper description on this (and it’ll need a name too) but it has had a mention in the literature and been on show a number a times. It’s incomplete and disarticulated, but it’s far from a bad specimen and very obviously has the classic features one would expect – a combined nasoantorbital fenestra, a big head, and yet some rather more basal features in the wings and feet.

Darwinopterus is the key taxon that helps us join up the basal pterosaurs and pterodactyloids, and there’s been a series of taxa named from the Chinese Daohugou beds that lived alongside this genus (a number of which are probably synonyms to be honest) as had made China the centre for this. Still, a couple of specimens from the UK have been found (or rather, rediscovered) that suggest these forms might have been more widely distributed and once they appeared in China, the Solnhofen and surrounding beds then became an anomaly – they were full of both pterodactyloids and basal forms, so surely the intermediates might have also hung around and been present given the numbers seen in China.

Now though a second one has turned up in Germany and it’s a lovely specimen of what is a small, and juvenile animal. The preservation is superb, and as Helmut Tischlinger has been working on it, there’s obviously some exceptional images, but there’s also some interesting features.

1

The short paper covering this animal is in German, so I might well be repeating things already said in the manuscript, but I’m going from only the English abstract and figure captions and my own thoughts, so this might be badly mangling or even completely replicating things already written. If so, my apologies to the authors or anyone else who has read the paper.

2

For me the more obviously interesting features all lie in the back end of the animal. First off as you can see below the distal phalanx of one wing had had a nasty break and then healed with a mass of bone that least the end at a rather major angle compared to the proximal part. There are a few pterosaur pathological wings out there, but this is quite a big one.

Secondly the tail is rather short. In my paper on pterosaur tails with Lu Junchang we suggested that Darwinopterus might have a tail of rather intermediate length between the classic ‘long’ and ‘short’ tails and this specimen might be going the same way. Not only that, but the tail also seems to have relatively short zygopophyses that are barely as long as the abutting centrum, whereas Darwinopterus at least has very Rhamphorhynchus-like ones that are very long.

The fifth toe also seems to be something of an intermediate – it is not a small nub like the pterodactyloids, but nor is the second phalanx that long and it’s not curved either as in other basal forms. Finally, the wing metacarpal looks to my eye to be rather longer than in other non-pterodactyloids. In other words, at least some of these features look to me not just to lie between the non-pterodactyloids and pterodactyloids, but actually somewhere between what we see in Darwinopterus-like animals and the pterodactyloids.

3

In short, this is not just a lovely-looking and intriguing specimen, but it certainly helps to fill in the ‘missing’ part of the Solnhofen and surrounding beds (this one is from Painten). Moreover, at first glance at least, it offers some tantalising prospects for looking at the evolution of characters towards the origin of the pterodactyloids and the changes especially to the wing metacarpals, tail and feet (all key characters for wings / control surfaces) and what this may have meant for their biology. More on this and other specimens is coming, so there’s some interesting work to be done and much to find out.

Tischlinger & Frey. 2014. A new pterosaur with mosaic characters of basal and pterodactyloid pterosauria from the Upper Kimmeridgian of Painten (Upper Palatinate, Germany). Archaeopteryx, 31: 1-13.

 

Edit: Helmut has asked me to clarify that in the paper he and Dino do not say this is an animal likely to be specifically part of the Wukonogpteridae (i.e. Darwinopetus and kin) but suggest it is closer to the pterodactyloids.

Sexual selection in the fossil record

Regular readers will know that for the last few years I’ve been slowly building a research profile concentrating on the behaviour and ecology of dinosaurs and pterosaurs. While the various papers on feeding behaviour, stomach contents, predation and niche partitioning in theropods has been the more high profile, I think the work on sexual selection is arguably more important as it potentially has profound implications for how we interpret all manner of fossils and how they may (or may not) relate to one another. After all, there’s a major ecological and taxonomic difference between identifying two species of a clade, and one species that exhibits major sexual dimorphism.

My colleagues and I have already looked at the idea that sauropod necks were driven by sexual selection, and after much strife, finally got a paper published discussing mutual sexual selection and the implications that has for diagnosing taxa in the fossil record and what it might mean for parental care and other aspects of behaviour. There’s more to come in these areas as I have further work planned and am involved in some other areas linked to this, so the area is growing rapidly and, I hope, ripe for a general revisit in the literature. However, while these papers have in large part being about drawing out some false assumptions in the literature and providing new hypotheses about sexual selection that could be looked at in the fossil record, they were a bit short on how this could be done, and were if anything, narrow in focus (not that Ornithodira is a small group, but its got nothing on Animalia).

So then to a paper in TREE that came out yesterday online. Led by entomologist Rob Knell, it also includes  Darren Naish and myself and attempts to provide a review of the entire question of sexual selection in the fossil record. We look at ways in which this could be diagnosed, some false dichotomies and assumptions that have been put forwards in the past, try to identify some key features that may help diagnose sexual selection and look at some of the more convincing cases for this that have been put together to date. Clearly there’s a limit to what we can get into under 10 pages for what is supposed to be a review, but I think there’s some nice synthesis in there and a bit more “we can try doing this”-type stuff, that just covering what has been said before. Anyway it’s out and available (though behind a paywall, sorry) so go take a look.

Knell, R., Naish, D., Tompkins, J.L. & Hone, D.W.E. Sexual selection in prehistoric animals: detection and implications. Trends in Ecology and Evolution, in press.

A new pterosaur appears

This is a bit of an odd post, but one I had to share. I got an e-mail from Helmut Tischlinger late last night saying that press release was going out in Germany featuring a new pterosaur. It’s from Wattendorf, is being worked on for a description at the moment and it apparently going on display today at the Bamberg museum. That’s all I know. I’m assuming it’s from the Solnhofen proper and it’s clearly a pterodactyloid and most likely a ctenochasmatid based on those fantastic jaws.

However, it looks superb and Helmut was good enough to share this photo (on which he retains the copyright, do not reproduce etc. without permission) with me which he gave me permission to put up here. So here it is, enjoy.

New pterosaur. Image copyright Helmut Tischlinger.

A very Brazilian pterosaur

Back in 2010, the Pterosaur.net boys and girls descended on Beijing for the Flugsaurier meeting. A good time was had by all (well, as far as I could tell) and while pterosaur researchers generally get together to argue, one of the things that was sorted out was that the next meeting would be in Brazil in 2013.

The conference fieldtrip in China included many a long drive in a minibus to get between the various localities and museum in Liaoning. On one of these journeys I had (what I thought) was a great idea for Brazil and John Conway was unfortunate enough to be sat next to me and feel the full force of Dave explaining his new concept. However, fortunately for me, John loved it and went with it. We pitched it as a possible logo for the conference and while they have picked their own (which is lovely) they have included our effort (I say ‘our’, John did the whole thing) on their pages, so it seemed an appropriate time to post this to a wider audience.

In my head I had the idea of pterosaur heads being bold and colourful, and that’s very true of the Brazilian flag. Add to that the huge size of some of their crests and at least one Brazilian genus, Tupanadactylys, that was big enough that it could pass for a flag at the right angle and with a bit of imagination. So here it is, a truly Brazilian pterosaur.

A post about a tail with no pun in the title

So onto the last major post about Bellubrunnus – the tail. The tails of rhamphorhychines are interesting as they have a somewhat unusual anatomy. Just like the dromaeosaurs (though obviously, convergently acquired) rhamphorhynchines have elongate zygopophyses and chevrons that overlap multiple vertebrae and bind the tail together so that it is a relatively stiffened structure. These extensions are basically rods of bone, and can long enough to overlap the four or five adjacent vertebrae to their origin.

However, Bellubrunnus appears to be unique among rhamphorhynchines in lacking these structures. It still has zygopophyses and chevrons (as can be just about seen in the figure) and compared to some pterosaurs at least these are long, but they are a fraction of the length of other closely related species. This begs the obvious question, of what happened – are these really reduced or is there some other factor at play? Well, there are a number of possible hypotheses to explain this and here I’ll go through them and why we have come to the conclusion that this is a genuine feature. Not all of the chevrons are there for sure, so some have been lost or remain cryptic for whatever reason, but several are quite well preserved and so the below discussions refer to the issue of the size and shape rather than presence / absence of chevrons.

First off, were these simply not properly ossified prior to preservation and were there, just as unpreserved cartilage? This seems really unlikely, even the smallest and youngest specimens of Rhamphorhycnhus (which includes specimens even smaller than Bellubrunnus) have fully ossified chevrons and zygopophyses. These seem to be present at a very early age in the pterosaurs that have them and so it would be odd if they had a different ossification pattern here. Indeed it would be doubly odd since if anything, Bellubrunnus has better ossification of its elements than is usual for small pterosaurs, with well-preserved and ossified tarsals and sternum. So it is far more likely that they are fully ossified, they are just much smaller.

Could these have been lost through decomposition or disassociation from the specimen, or may not have been preserved even if they were ossified? While a few pieces have begun to disarticulate and move (the gastralia and a few dorsal centra and the prepubes) nothing else on the specimen has really begun to move and indeed the caudal vertebrae as a whole is well articulated. It would be odd indeed if the only thing to have rotted or moved was the chevrons or parts of them, while the rest remained intact and complete. Similarly, with even tiny parts like the delicate palate and gastralia being preserved (and indeed at least a couple of chevrons) it also seems unlikely that these somehow resisted preservation when everything else is there. Certainly it’s possible, but even so, some are still there and the loss of many chevrons would not affect the shape of the ones that have survived and wouldn’t affect the zygopophyses.

Were these destroyed or modified through preparation? This is a tricky one to answer, but again, there’s no obvious reason to think so. The preparation job is superb (look at the skull!) and was done with great care and attention to detail. It’s always possible that thin and delicate structures were lost, but while the matrix has been all but scraped clean, at least some have survived (and again lots of other delicate things) and I find it hard to imagine they were modified in such a consistent manner.

Are these genuinely distinct then? That is the obvious conclusion given the problems with the other hypotheses. However, there is more than just negative arguments against these other ideas, but there are reasons to positively support the idea that these are genuinely short. Although greatly reduced in length, the anatomy of both the zygopophyses and chevrons is otherwise well consistent with the anatomy of these features in other rhamphorhychines. The zygopophyses are rather rod-like and then taper abruptly to a point, just as we see in others, only with a much shorter rod. And similarly the chevrons are long and thin and splint-like, terminating in a point at each end, just as we see in others, only again being rather shorter.

While as noted we are rather short of chevrons for whatever reason, those that remain and indeed the zygopophyses seem to have a genuinely distinct morphology to other rhamphorhynchines, including similarly small and young specimens of Rhamphorhycnhus. This then is a major anatomical difference that separates Bellubrunnus from its nearest relatives as well as providing a little more interest and intrigue in the origins of this structure since while it is present on all other rhamphorhycnhines, it’s also present in basal pterosaurs outside the group and so may well have had multiple origins and losses.

Brunn – not the Solnhofen

At the end of my last post I raised a most significant point – Bellubrunnus isn’t a Solnhofen pterosaur. While it’s easy to think that those Jurassic lithographic beds from Bavaria are the Solnhofen, it’s not the case. Like all rock records, different divisions are known and are grouped in various hierarchical clusters. The Solnhofen is home to a lot of important species (Archaeopteryx for starters, not to mention all the pterosaurs and insects and plants and fishes) and a good deal of work has gone into working out the stratigraphy of all these different fossil-bearing beads, but not all lithographic limestones lie in the Solnhofen.

Obviously this doesn’t mean that an animal from one layer right above or below the Solnhofen didn’t overlap in time with other strata – the rocks don’t delineate when and where species lived. However, Brunn is rather older than even the oldest Solnhofen beds and from the Kimmeridgian rather than the Tithonian. While the rocks are of a similar kind and were put down in a similar manner in similar ecosystems, the two are different.

Work on the Brunn beds are still very new and I must confess I’ve not looked into it in any great detail (not least as all the literature seems to be in German) and have had to rely heavily on my colleagues here. Still, the two do seem to contain different taxa as a whole and while to date the higher vertebrates at Brunn have been few and far between, given the quality of the preservation, I don’t think there’s any reason to expect that we won’t get a lot more in the future. Moreover this does suggest that Brunn is different to the Solnhofen and so we might expect a different (if closely related) fauna to be present. In short, the fact that we now have literally hundreds of pterosaurs from the Solnhofen and no record of Bellubrunnus there, supports the idea that this is a different genus, and also the idea that there might be many more new pterosaur species in there to be found. At the very least, there is a lot more to learn from the Brunn biota.

One last point to address here lies in the temporal distribution of rhamphorhycnhines. The recently described Qinlongopterus is also known from a single, small, and young specimen, though it heralds from the Middle Jurassic of China. As described this taxon is really rather similar to Rhamphorhynchus and it was suggested that as such, the rhamphorhycnhines might be really rather stable as a group and went long periods of time with little morphological change. Obviously Bellubrunnus interrupts this apparent trend, as compared to the Middle Jurassic of China, it’s much closer in time and space to Rhamphoprhynchus, yet does have quite a few differences. This is probably due to that fact that unlike Bellubrunnus, Qinlongopterus is really badly preserved, and morphological information is rather limited. What can be seen in Qinlongopterus is very Rhamphorhynchus-like, but that’s not saying much since the condition of it means that not all the many details can be seen. Plus of course the young of species tend to be much harder to tell apart than the adults, since, well they don’t have all their adult features yet and typically the younger they are the harder that will be. So in fact this ‘stability’ is illusory based on the age and condition of Qinlongopterus and in any case is interrupted by the emergence of Bellubrunnus and its differing anatomy.

And on that subject, next up, that interesting tail…

Bellubrunnus – definition, diagnosis, and why it’s not Rhamphorhynchus

Right, lets crack straight on with dealing with the details of this lovely little thing. First off, if you have read this post on pterosaur ontogeny, you should be able to recognise that while Bellubrunnus is small (in fact it’s tiny, with a wingspan under 30 cm and a skull just a fraction over 2 cm), it’s also very young. The head is proportionally huge, and the eyes (represented by the sclerotic rings) are massive too, lots of neurocentral sutures are open (as can be seen by displaced centra in the dorsal series) and the wrists, pelvis and scapulocoracoids are unfused, and even the skull is coming apart. Unusually for such a small pterosaur though, the tarsals are well ossified, though they are rather amorphous in shape, which is a classic feature of young pterosaurs.

This then is a very young animal. That does of course complicate issues a little as obviously some things change during growth and we don’t want to misdiagnose this by thinking it has some unique features which are in fact simply a result of its age. On the other hand though, following mostly from the work by Chris Bennett, we have a good idea of the ontogenetic changes undergone by Rhamphorhynchus as it grew so we do know what kinds of things change as they grow (and so can be avoided, or used carefully) and which don’t (and can be used pretty freely).

Lets start with the most obvious thing – Bellubrunnus is a rhamphorhynchoid pterosaur. It has a proportionally small head (compared to the size of the animal as a whole, and the body specifically), short neck, short wrist and pteroid, short metacarpal IV, long tail, long 5th toe and other characteristics. Moreover, it’s also a rhamphorhynchine – a derived member of this basal assemblage and close to things like Rhamphorhynchus and the recently described Qinlongopterus. Bellubrunnus exhibits a number of characters associated with this clade such as the shape of the deltopectoral crest and the proportional length of the wing finger.

Bellubrunnus is also really rather like Rhamphorhynchus which might be no surprise given the rocks it heralds from (though more on this later) – the area is kinda famous for producing specimens this genus in serious numbers. The two share a number of characters previously used to diagnose the latter alone such as edentulous jaw tips, a femur shorter than the humuers, and an H-shaped prepubis. However, the two also have some rather notable differences that clearly mark them as different taxa. Among other things, Bellubrunnus has only 22 teeth (or perhaps even fewer) compared to some 34 in Rhamphorhynchus, it has a rather different tail anatomy (more on this to follow as well) a different humeral shape, and several major proportions of the limbs are quite different.

The point about proportions is quite a significant one. Proportional ratios between various elements are common characters for pterosaur taxonomy and systematics, but unhelpfully, we also know that some of these change during ontogeny in at least some groups. So we do need to be careful and this is no exception. The best example here is the ratio of the humerus to the femur – in Rhamphorhynchus this seems to get larger as the animal gets bigger. Small (and so young) specimens tend to have a lower ratio and adults a high one. Bellubrunnus is among the smallest pterosaurs known and comparable in size to the smallest (and youngest) specimens of Rhamphorhynchus, but it’s ratio is the higher than any specimen of the other genus.

While I’ve not mentioned it here, in the paper we do compare this to other members of the rhamphorhynchine clade and provide similar numbers of difference in things like tooth count, anatomical features, skeletal proportions and the like. A number of these taxa are rather fragmentary and hard to say too much about, but do always differ from Bellubrunnus.

So in short while we can be sure this is a very young animal, we can also be confident with our assignment to the rhamphorhycnhoids and rhamphorhynchines, and while this would appear to be a close relative of Rhamphorhynchus, it’s also clearly quite different in a number of characters, marking it out as a new and distinct taxon. One last point needs to be raised here too as a launch-pad for the next post, Bellubrunnus is from Brunn, and Brunn, well it’s not actually part of the traditional Solnhofen that is home to Rhamphorhynchus. It’s older and the two were not contemporaneous.

Introducing Bellubrunnus

Visitors to the Solnhofen Museum in Germany in recent years might well have seen a delightful specimen of a small Rhamphorhynchus on display. While clearly a nice little find, it was hard to see too much detail under the glass given how a) small it was and b) just how close in colour the bones were to the matrix it was preserved in. Certainly I didn’t give it much more than a glance when I first saw it as part of the Flugsaurier fieldtrip way back in 2007, and I’m not sure that many of my colleagues did either (though to be fair we had only an hour or two to try and do the whole museum, and well, if you work on pterosaurs you generally have seen a lot of Rhamphorhynchus material).

However, while I was in Dublin, a PhD student working on Solnhofen jellyfish pointed me back to this as something worthy of more special interest. Once I had some decent photos of it, it was clear that it was indeed something rather more special than just a young and complete specimen of Rhamphorhynchus. Indeed, while clearly having a lot in common with this very well known genus, there were some obvious and pretty significant differences. Talking to the curator at the Solnhofen, Martin Roeper, I discovered that (perhaps inevitably) Helmut Tischlinger had already taken a number of UV images of the material and he and Dino Frey had planned to work on it, but things had fallen behind. A few more exchanges and I was generously offered the chance to lead the formal description of the material and write up this interesting find.

That paper has now been completed and indeed published, and as such the inconveniently labelled specimen BSP–1993–XVIII–2 should now be known as Bellubrunnus rothgaengeri. The species name honours Monica Rothgaenger who led the team that uncovered the material and donated it to the museum (note that while this has a BSPG number, it is on permanent loan to the Solnhofen). The generic name comes from the locality of the matieral, Brunn, and the Latin ‘bellus’ meaning beautiful. This is the beautiful one from Brunn, and well, as you can hopefully see, it really is a superb specimen. It’s effectively complete and articulated and preserved in ventral view. While it is indeed hard to make out too much detail under normal lighting conditions, under UV, the difference between bone and matrix is obvious in the extreme and the details quite apparent and with tiny and fragile parts like the sclerotic rings, the palate, the tarsals and prepubes being preserved. Sadly though, there’s no sign of a single jot of soft tissues anywhere, despite the superb (indeed, unusually good) preservation of the bones. The matrix around the bones has been prepared right down to help expose them and you can see the scrape marks of preparation tools around the specimen.

Happily for all fans of sci comms and outreachy things, the paper is in PLoS ONE (the latest in quite a series for pterosaur work this year it must be said) and so freely available. There is, inevitably, a lot to be said about this animal and while the paper IS freely available, I think that there is a good mine of interesting things here that help reveal ideas about pterosaur evolution and anatomy. And let’s face it, even with the best will in the world, it can be hard to fight through a long paper, and it’s rather easier to read a few blog posts. That said, obviously with the paper being freely available, if you do want more details and specifics and citations etc. then the paper should be the first place you look.

This post then is perhaps not so much more than a holding pattern while obviously showing off the material itself, and this superb life reconstruction by Matt van Rooijen (which is also in the paper and so available) whom I must thank for his superb efforts. I’m not going to try and spin this out too much, but there are some nice areas of interest about Bellubrunnus that can be easily separated from the rest and make nice short and self-contained posts, so I’ll try and do just that. We’ll start almost immediately with the most obvious question – what exactly is it?

Hone, David W. E., Helmut Tischlinger, Dino Frey & Martin Röper. 2012. A new non-pterodactyloid pterosaur from the Late Jurassic of southern Germany. Public Library of Science ONE.

Horniman pterosaurs

Yesterday I put up some photos of the gloriously anachronistic dinosaurs at the Horniman museum. As you’ll have already deduced from the title that they also had a couple of pterosaur models. While presumably hailing from the same era (and perhaps even that same artist) they are not quite as inaccurate, though this is, I suspect, more to do with the fact that our ideas of pterosaurs have changed less over time (or in some cases returned to an earlier idea), rather than any greater level of detail being paid to the pterosaurs.

While there are (inevitably) some mistakes, the only really standout one is the neck of the Pteranodon. It’s absolutely tiny and makes it look like the head has just been welded onto the body. Given that one of the defining characteristics of the pterodactyloids is the long neck, and that in Pteranodon it should be about half to two-thirds of the length of the skull, this is far from a good representation of a pretty basic bit of anatomy.

Pterosaur ontogeny

 Not too long ago, Matt Wedel had an SV-POW! post that talked about ways of diagnosing an adult vs non-adult sauropod. Inspired by this and the fact that I have recently been playing around with issues of ontogeny in pterosaurs, I decided to write something similar for the non-avian Mesozoic fliers. If you have a pterosaur specimen in front of you, just how do you know if it’s an adult or not?

Obviously there are some general indicators that are pretty good for vertebrates as a whole that will get you quite a long way (even if this is a new species). Size is obviously rarely a great indicator, but if you have a pterodactyloid with a 20 cm wingspan then it’s going to be a juvenile, and likewise if you have a rhamphorhynchoid coming in close to the 2 m mark it’s very unlikely to be anything but a big adult. Young animals (and especially very young animals) tend to have big heads compared to their body and especially very big eyes compared to the size of the head. A bunch of fusions are absent in young pterosaurs that are present in adults too, just as you’d expect for most animals. The sutures between the centrum and neural arch of the vertebrae will be open in juveniles and closed in adults, and similarly the elements of the pelvis and sacrum, and the scapula and coracoid will be separate in young animals and fused together in adults.

Pterosaurs also have some characters of ontogenetic change that are rather more peculiar to them than vertebrates in general. Very young pterosaurs also tend to have a very grainy texture to the surfaces of their longbones, despite the fact that even embryonic pterosaurs have a pretty ossified set of bones (unlike many young animals). Smaller pterosaurs also tend to have various parts of the skeleton being less ossified and rather amorphous compared to those of adults. The tarsals are often not well ossified and can be missing (well don’t preserve) and if present may be very simple shapes. The carpals tend to look more ‘blobby’ and lack the detailed morphology seen in adults and will be separated into multiple elements whereas in adults the wrist will primarily be formed of just two massive elements (plus the pteroid). Finally, while obviously you would expect skulls to fuse up during ontogeny, pterosaurs do tend to take it one step further than most. Rather like birds, in adult pterosaurs the sutures all but disappear, or even go entirely, such that the skull looks like a single smooth piece of bone. Also as in some birds, bigger pterodactyloids have a notarium and this only fuses up and fully develops in adults. Similar to the point above about absolute size, the presence and development of some form of head crest is indicative, but not a great indicator of age. Yes a massive and elaborate crest in an animal is indicative that it’s an adult, but there could be a fairly well developed crest in an animal that is close to becoming and adult and of course there are taxa without crests and in at least once case it appears that females don’t have crests.

As in mammals, but unlike dinosaurs and birds, pterosaur also have epiphyses. The growing plates at the ends of the long bones physically separate the main shaft of the bone from the proximal and distal ends, so things like the femur can appear to be in three pieces. Obviously as growth slows towards maturity these epiphyses slowly disappear as they fuse into the single element that you would expect to see.

So in short, something that is small, with grainy textured bones, a big head, with big eyes, unossified tarsals, amorphous carpals, no crest, clear sutures in the skull, no notarium, and separated scapulocoracids, pelvis, epiphyses and neurocentral sutures is going to be a young juvenile. And the close these various features get to the opposite condition the closer the animal is likely to be to adulthood.

As ever with such things these are not absolutes, but merely guides. Good guides, certainly – you simply won’t see a notarium in a very young pterosaur, or open neurocentral arches in a big, old adult. However, in terms of determining more subtle difference in age it will be tricky – one animal may have fused up the notarium, but may have incompletely ossified tarsals and another could have the reverse. Although at least some characters do seem to have a bit of a pattern (the scapulocoracoid seems to fuse pretty early in most things) a general lack of numerous specimens of different ages makes it hard to do any more detailed analysis. Still, in terms of gross age (hatchling – young – adolescent – adult) even for a specimen of a previously unknown species with no obvious close relatives, it should be relatively easy to determine the approximate age of the animal.

Parapsicephalus

A last left-over AMNH pterosaur and again I’m most grateful to Steve Cohen for the photos. This is all there is of this little taxon (assuming you think it’s valid – Dave Unwin sank it into Dorygnathus, but Kevin Padian kept it separate in his more recent review of Dorygnathus). I don’t know where the original specimen is, but as it was from the UK I assume it’s here and that this is a cast, but if so it’s rather a good one.

The view here is dorsal, looking down on the skull (well, most of the skull) with the posterior part at the top of the picture and the snout pointing down as seen. As you can hopefully make out, this is essentially an incomplete skull which as I recall has no teeth in it. Just another incomplete pterosaur, but nicely preserved and in 3D which is always a bonus for such a basal animal.


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