Archive for March, 2020

Big wings in the Solnhofen

The Solnhofen limestones of Bavaria are famous for their well-preserved fossils and for a pterosaurs researcher, the plethora of specimens and taxa that are represented. Finds continue to this day and we now have more species known from more specimens than ever before, including from a variety of a branches of the pterosaurian tree. The Late Jurassic was an interesting time with the pterodactyloids diversifying, the non-pterodactyloids soon to fade (though doing pretty well) and a few intermediates (wukongopterids, or if you prefer, darwinopterids) are still about. One thing that is true of all of them though is that they are not very big.

While later pterosaurs are famous for producing numerous lineages with wingspans well in excess of 4 and 5 meters and all the way up to 10, before the Cretaceous, there’s basically nothing that even gets up to 2 m in wingspan, and even those tend to be relative giants and quite rare. This is especially true of the Jurassic pterodactyloids which really don’t seem to have got going yet in the size stakes. However, there are some tanatalising hints of bigger individuals or even big species with various bits of limb elements (and slightly bizarrely, some isolated but articulated feet). Not much has been done with these in part because they tend to be very incomplete.

However, quite a few years ago now, Dino Frey at the Karlshue museum in Germany acquired a complete and articulated wing of a large Solnhofen pterodactyloid. It was much bigger than any other known complete wing and it eventually feel to Ross Elgin (then a PhD student under Dino and myself) to work on. We started on this and worked up a manuscript and then sometime later I happened to be in Berlin and spotted on the wall of the collections, another, equally large (though rather less complete and less well preserved) Solnhofen wing. This has apparently sat all but ignored for many years and as far as we can tell, it’s never featured in any paper or been referred to before. So now we had two wings to describe, each of which would have been from an animal with a wingspan of just over 2 m and they turned out to be pretty similar to each other, but what were they?

Working out what they were took some work. After all, it’s perfectly possible that these represent known taxa, but are merely unusually large individuals. And with only the wings to go from, a lot of the anatomical data you would normally want from the skull or some gross proportions of the neck, legs and so on are missing. To make it more awkward, we don’t have a great understanding of the growth patterns of many pterosaurs so it’s not obviously what the trajectories might be of the rarer species where we have only a few specimens.

Looking in detail at our two wings and various other larger Solnhofen pterodactyloids and other isolated large wings showed that these two new ones are different to each other and there are likely two different ‘big wing’ morphs present. A number of major pterodactyloid clades are either around or at least suspected to be present in the Jurassic, and so there was a wide range of possible candidates. However, the anatomy present ruled out most of them (ornithocheiroids, istiodactyloids, azhdarchoids) though it did leave the identity uncertain and they could be ctenochasmatids or very early dsungaripterids.

So while we don’t know exactly what we have here (and we suspect there’s a new taxon in this material based on some unusual features of the Karlsruhe specimen) it is still interesting stuff. We now have a good record of all the largest Jurassic pterodactyloids and clear evidence of animals of over 2 m wingspan. We also have much more detailed information on their anatomy and while the exact identities are uncertain, it looks like there is more diversity here than previously realised and that there are more taxa to be discovered. New specimens are still being uncovered in the Solnhofen so hopefully it is only a matter of time until we have complete, large, pterodactyloids before the Cretaceous.

The paper is open access and fully available here.

Elgin, R.A. & Hone, D.W.E. 2020. A review of two large Jurassic pterodactyloid specimens from the Solnhofen of southern Germany. Palaeontologica Electronica.

Toronto Zoo

Snow leopard

Take a long drive (or in my case, an interminable bus ride at the end of a subway line) north of Toronto and you eventually come to the zoo. Thus despite the name this is not a city zoo but one very much out in, and even beyond, the suburbs (wild turkeys were present alongside the bison for example). As such it’s a very large zoo, which is always nice when it means that the larger animals have a lot of space but be prepared for a good workout with some decent hills thrown in too.

One nice hallmark of the zoo was the extensive collection of ‘local’ species – groups of both prairie bison and the wood bison subspecies (your definitions may vary), moose, bobcat, wolves, polar bear, snowy owls and Arctic fox (a new species for me) and others were all present and correct. Indeed, the polar bears were about as well kept as I’ve ever seen and one in particular was taking great delight in sliding down the snowy banks of the hill in its enclosure and rolling around in the snow. Much as LA Zoo makes great use of the local weather to keep lots of tropical species outside, Toronto does well in the same vein with cold weather species with things like snow leopards and ibex in addition to the Canadian animals.

Giant African soft-shell

They do though also have lots of more ‘traditional’ species and it’s rather neat to see white lions, rhinos and hyenas in the snow. Of particular interest though were the several walk-through tropical and temperate houses that had some especially neat animals. One house was linked to various species that had access inside and out including relative locals like beaver (sadly not visible) and grey shrike. It was especially cool to see the extremely rare black footed ferret though this spot was tempered somewhat by the fact that it was only visible as a sleeping ball of fluff.

I also got to tag some other species that have loomed a long time on my list of animals I wanted to see. First off was a pair of wombats which were everything I’d wanted and even were good enough to move around a bit and nearby in the Australian section were some galah cockatoos which was neat to see too. Sadly, the allegedly existing but not actually visible short-beaked echidna repeated the trick of it’s conspecific in the Berlin Tierpark and was underground and invisible.

Tentacled snake

On the upside though I did get two more stellar reptiles and both in the larger walk-through house that included pygmy hippos, crocodiles and numerous birds. First off a tentacled snake which was kind enough to sit near the glass allowing me to get a decent photo of this essentially aquatic animal. The second was another aquatic specialist, an African soft shelled terrapin. It was a huge one and much larger than I’d expected and was sat out on the bank but did extend and retract its neck which was fascinating to watch.

All in all, it’s a very good zoo, but be prepared for a long day and a decent hike. Even skipping some of the more distant parts of the zoo will still involve a healthy bit of exercise but it’s a great collection and, rarely, one that is very rewarding to visit in the deep of winter.

Wombat!

 

 

 

A little more Luchibang

Life reconstruction of Luchibang by Matt Van Rooijen

After the previous mammoth post on the long and painful history of the publication of the new paper, I still wanted to write a little more about the specimen and what we have learned. As noted in the first post this specimen is preserved alongside a couple of fish and apparently has some soft tissues associated with it.

The istiodactylids are one of those groups where their ecology has been very uncertain with a variety of activities suggested. Based on their affinities with the highly piscivorous ornithocheiroids it’s been suggested they were fish eaters, though their teeth don’t look well suited to catching fish at all, and that little cluster of interdigitating and cutting teeth has been used to put them forwards as scavengers. That doesn’t sit too well either since they appear to generally be quite aquatic in their habits and while we have a great many birds that are specialist scavengers today, none of them are marine soarers.

Luchibang doesn’t actually help resolve this much. While it’s limb proportions and especially long legs point to greater terrestrial competence and might point to an animal that is therefore scavenging more, it’s also preserved with two fish specimens. One of these is down and under the ribs and apparently in the ribcage. In the paper we are cautious over this specimen as small fish are commonly associated with these kinds of Liaoning specimens (indeed, there’s one already here by the head which clearly wasn’t’ eaten) but it is certainly possible that it represented preserved stomach contents.

So we can provide some tentative evidence to support both scavenging and piscivory in this animal (and of course these are not mutually exclusive positions) and so while what we have here is interesting it doesn’t resolve much. This uncertainty is reflected in the very nice life reconstruction that Matt Van Rooijen kindly did for the paper (quite a few years ago now, he’s been sat on it a while!). In the foreground Luchibang is wading in the shallow waters and grabbing a fish while nearby is the carcass of an iguanodontian which is available as an alternate source of sustenance.

One last thing to comment on is the preservation of soft material on the specimen that we interpret as soft tissues. It is really rather poorly preserved and is little more than some stains on the rock but with some regular patterning and shape that appears to be organic. There are several spots and they all look similar and are associated with the skull, the neck and the ulnae. They don’t appear to be parts of the wings suggesting these are skin traces. There’s no indications of any pycnofibers but then, assuming these are soft tissues, they are rather decayed.

That’s quite enough on Luchibang for now, the paper is fully open access so you can read the full description and discussion there. This only leaves me to thank Matt for his artwork, my coauthors and the referees and editors on this paper.

 

 

Ten years in the making of Luchibang

Some research papers can take a long time to finish and delays for all kinds of reasons can put projects on hold indefinitely or even kill them eventually. Luchibang has a particularly long lead up time but the history of this description and naming take in a whole bunch of issues over publication which are informative and important.

To begin at the beginning, way back sometime around 2010 (or possibly even 2009) while I was doing my postdoc at the IVPP, Xu Xing came to my office and asked me to look at a pterosaur specimen. A colleague of his was looking to acquire it for a museum and had been assured it was a new taxon but wanted confirmation. It was, of course, what has become the holotype of Luchibang, and it was immediately obvious that this was unusual and new with the large legs and somewhat odd tooth arrangement and so after a few minutes of checking various details and cross referencing with a few papers, the curator left happy.

A few months later the specimen was back as I’d been invited to describe it. I really hadn’t expected the opportunity and was delighted to do so and so set about the task of doing a full description. I didn’t include a phylogenetic analysis for a number of reasons, but notably as the specimen was so clearly an istiodactylid and their own relationships were rather unresolved, adding what was obviously a juvenile into the mix would have been a fair bit of work to not actually add any real information.

Looking through my files this was submitted sometime in late 2010 or early 2011. The paper came back from review after a time when I had left China and was now in Ireland, with one referee liking it a lot, but with the other review came a bombshell. They through the specimen might be a composite.

This was obviously a huge problem because first, I was worried it genuinely was and I’d somehow missed this and second because now I was back in Europe the specimen was hardly easy to access, and proving it was genuine was going to be tough. The referee pointed to the unusual hindlimbs and what they thought were unusually long cervical vertebrae and suggested this was an azhdarchid body on an istiodactylid head. My lack of phylogeny had also come back to haunt me as they suggested an analysis where the head and body were coded separately should reveal what respective animals they might come from. It then took me about three years to be able to begin to resolve this issue. Eventually I did get back to see the specimen and was able to do the most important thing to show it was genuine – to reprepare bits of it myself by hand.

The matrix and even the bone vary quite a lot in the specimen and that’s quite common in various specimens from Liaoning so this itself was no concern. It was suggested UV photographs might reveal any shenanigans, but work Helmut Tischlinger and I had done on several specimens at the IVPP showed that even those collected and prepared by the museum could show dramatically variable reflectance on single slabs and this would be unreliable in this situation (not that Helmut was around at the time either!). So instead I set to the specimen with some picks and carefully chipped away at the matrix at various points on the specimen where the head met the body. There was no glue, no cracks, no joins, no restoration, only natural and original sediments. Checking the margins of the slab also showed no cracks or joins where a piece could have been incised into the rest of the specimen and again, no traces of glue or other tampering at the margins. The very tip of the snout also is broken off at the margin of the specimen which helps trace the bones to the very edges. Critically, if you look closely it’s also clear that every part of the main skeleton is in direct contact to another part. The bones of the skull actually touch those of the neck, which contact those of the wings and chest, which contact the legs. If the head had been added to the specimen, it has been done to make the bones touch each other and even merge with each other (this happens on flattened specimens) and with no joins between them under preparation. In short, this must be genuine.

I have seen plenty of faked, and otherwise ‘improved’ specimens at various times and they are never even close to looking convincing once you study them in detail (and most are not convincing at all) and there’s some other circumstantial evidence to support his being genuine. Despite the odd loss of the back of the head, we’d expect in such a juvenile animal that the skull bones would not be fused together and so the ontogenetic status of the head does match the body and the proportions are about right too. It seems unlikely that not only were people able to insert a skull perfectly onto a postcranium but did so with an animal of the right size and growth stage (and why would they not put in a complete skull at that?). Minor points compared to the lack of evidence for any tampering, but all suggesting a genuine specimen.

Despite the lack of a phylogeny, I now wrote to the editor of the journal and pointed out that I was now able to confirm that the specimen was genuine. I’d been able to show that some of the alleged azhdarchid traits were actually shared with some ornithocherids too reducing that side of the equation, and I had even had a PhD student who was in China at the time do some prep themselves and confirm my observations and was able to have them send a supporting letter to support this. To my dismay, despite having previously agreed this would be sufficient, the editor now said they didn’t think it was enough to support publication of the specimen and they wanted to see some systematics.

I no longer had access to my systematics programs and while a couple of times I approached potential coauthors to help me run some phylogenetics, no one with the expertise I needed had the time. With my career now changing and my having less and less time for such work and the frustration of the delays the whole project fell to one side. I couldn’t convince the editor and didn’t have the time to do the new analyses and couldn’t get help with it. I didn’t abandon it, but nor did I think it was ever going to get done. I also had doubts about being about to convince any other referees or journals about the specimen so didn’t want to invest time and just have the paper bounce from journal to journal.

Then came the most recent Flugsaurier conference in LA and this coincided with my having a bit of free time. I decided this would be a great opportunity for a test case – I could present the specimen to a whole raft of researchers and lay out everything as I’ve done here and see what people said. After all, various experts on istiodactylids, ornithocheirds and azhdarchids would be there and the collective knowledge in the room would be greater than mine and a couple of coauthors and referees. In creating the talk, I was also able to delve back into the pterosaurian literature and with many years of new papers and in particular phylogenies meaning there were lots of new traits described and defined that could be used to support various taxonomic affinities. This really helped as I could now also find more traits in both the vertebrae and even the long legs that were clearly ornothocheiroid in nature and not azhdarchoid.

To my delight the audience was very receptive to the idea and only one person flagged a single trait that they thought might compromise my diagnosis as it should be present but didn’t appear to be. Talking to them more about it afterward and going through some photos we were able to establish that this was there as well and the apparent last of the questions over the possibility of any fakery were removed. Still though, a phylogeny would be nice and at this meeting I met Adam Fitch who was playing with pterosaur phylogenetics and had the time to get involved. We ran analyses to show that both the head and postcranium independently clustered with other ornithocheirids and I wrote a section to provide the evidence that the specimen was genuine. So the paper was dragged out into the light, got updated and revised and had a new phylogeny added that Adam and I produced. And so, submission and plain sailing to publication.

If only.

The first journal we sent it to rejected it with a long review pointing out that we really shouldn’t have included a lot of information showing the specimen was genuine. If there was any question about it, it shouldn’t be published at all, so we should take that information out. So the paper was revised, the material relegated to the supplementary information and onto the next journal.

This time it got rejected with the referee noting that the specimen either was actually a weird toothed azhdarchid or might not be genuine and we should include a clear explanation as to why we thought it was. They clearly hadn’t read the supplementary info with several pages of material on this exact subject or considered that maybe the long list of traits that we showed were homologies of ornithocheirids and istiodactylids. To make it worse, that same person then phoned me a couple of months later to say they’d seen a very similar specimen in another lab in China. So not only is there allegedly another one out there (making this seem more likely to be genuine) but now after all this time we might get eaten to the punch by another lab while we were being rejected for publication based on the review of a person now telling me they thought it was genuine.

So, we submitted to Palaeontological Electronica. It meant we could include lots of colour images and come out with an OA publication and importantly they require a four week turn around for reviews. Of course the paper then sat with the journal for nearly four months and several e-mails went ignored by an editor which only added to the frustration. During this time a new istiodactylid was published from China and then a near-complete specimen of the very closely related Mimodactylus meaning the paper managed to get out of date more in 3 months in review than it had in a 10-year hiatus. Eventually the reviews came back and the only substantive comments from the referees were that we should include the taxa which had just come out while our paper was in review. That meant redoing the phylogenetic analysis which wasn’t trivial (and it yielded effectively identical results), but we were able to return the paper fairly swiftly and now it’s finally out.

Hopefully this goes a very long way to explaining the various dips and delays in taking this specimen from first penning a description a decade ago to coming out now. Self-imposed breaks, unavoidable delays in accessing the specimen while on the wrong side of the world, other commitments, and recalcitrant referees and editors have all played a part. Establishing that the specimen is genuine was obviously important once the spectre had been raised, and it clearly improved the paper by forcing me to refine my arguments and make more detailed comparisons with various other taxa and by delving deeper into their anatomies. That said, it was a huge issue I could have done without and the timing could not have been worse as I’d just left China. This is though, the end of the tale now that the specimen is published, but there’s still more blog to come on the wonderful (and rather late) Luchibang.

A long overdue welcome to Luchibang

 

Luchibang has arrived

Today sees the publication of a new pterosaur that has been a very long time in coming. There’s a hell of a lot to unpack here with both the animal itself and the history of the research so this is going to take quite some time to get through. So, here’s the start of a lot of information on this really rather unusual animal.

First off, this is an istiodactylid. These are a branch of the pretty familiar ornithocheiroids which include things like Anhanguera and Ornithocheirus and (according to most researchers) aare close to Pteranodon too. In short, a group of medium to large sized, ocean-going fish eaters, many of which have lots of large grabby teeth to go with big wings and small legs. The istiodactylids are really rather unusual in that they have only a few small teeth at the front of the jaws and they also have giant fenestrae in the skulls which makes them very recognisable. Apart from the eponymous British Istiodactylus, they are all known from China which has really quite a diversity of them though in varying degrees of completeness. This is another specimen attributed to the Yixian Formation and its diverse pterosaur biota.

Luchibang immediately becomes important as it’s by far the most complete known istiodactylid. It is, unfortunately, crushed nearly flat, but apart from the back of the skull, the tail and few tiny bits, everything is there. There’s even rare elements like the gastralia and sternum in good condition and there’s not too much overlap of bones meaning everything is visible (though often at odd angles). The loss of the back of the head is especially annoying but otherwise this is an exceptional specimen. This alone would make it important but it also has some patches of what may be soft tissues in places and it’s also apparently got a fish preserved in the chest cavity (more on this later). One top of that, it’s also really big, or at least would have got bigger. The specimen is about 2 m or so in wingspan but it is also a very young animal. One of the major fusions of various elements that we see even in some relatively young pterosaurs, let along subadults or adults, are present and so this animal would have been considerably larger at adult, perhaps being one of the largest istiodactylids.

The skull and upper body of Luchibang xinghe

If you take more than a quick glance, it quickly becomes clear that while Luchibang has the incredibly typical head and tooth arrangement of istiodactylids, it’s also got a few very odd features. Most obviously, the hindlegs are really long and the feet are very big. Although rather incomplete, there is no evidence for anything like these proportions in other istiodactylids or the ornithocheiroids as a whole and marks it out as being quite unusual. In fact, when we plot out the proportions of the fore and hindlimbs, Luchibang plots over with the azhdarchoids rather than other ornithocheirids and otherwise the two groups are quite distinct in their anatomical arrangements.

This rather strongly suggests that Luchibang is doing something rather unusual and was much more terrestrially capable than its relatives and also then led to its name. Luchibang translates from Chinese as the ‘heron wing’ to convey the apparent heron-like attributed of long legs and catching fish, with the species name xingzhe meaning ‘walker’ also relating to this. Although this name was first created many years ago, while this manuscript was making its way through development hell, the pterosaur community lost palaeontologist Lü Junchang. JC, as he was generally known, was a friend and collaborator on various pterosaur projects and so this new taxon then became a great opportunity to honour his work and his memory and so the etymology formally recognises him too.

So, welcome JC’s walking heron wing, and in the next post I’ll talk some more about the long and tortured history of this publication which dates back a full decade.

 

Hone, D.W.E., Fitch, A.J., Ma, F., & Xu, X. 2020. An unusual new genus of istiodactylid pterosaur from China based on a near complete specimen. Palaeontologica Electronica.*

 

*Yes, there’s an error in the abstract with their weird hanging ‘postcranial’ in the last line. We asked the journal to remove it at the proofs stage but they refused because it had already gone for translation, so we can’t fix it. Feel free to mentally delete it yourself. And the ‘original’ planned species name of ‘wuke’ has managed to sneak through the proofing process and appears in Fig 8. Annoying and stupid but doesn’t affect the taxonomy, though it means I’ve effectievbly accidentally created a nomen nudum.


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