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Titanosaurs and other Somphospondyli by Paleo-King Titanosaurs and other Somphospondyli by Paleo-King
This is a basic outline of the Titanosauriform "family tree" as I see it so far. It is NOT a finished product, and may be updated as new information is found. It is based on comparative analysis of overlapping elements of as many known species as possible, as well as features and morphology beyond what is normally included in "strict consensus" trees. For the time being I have left out Klamelisauridae and other possible "stem-titanosauriforms" more basal than Brachiosauridae. The tree is constructed based on visual data and taxonomic character inferences from many papers (I have over a hundred sauropod papers, most of them macronarians), though the positions and synapomorphies in these papers that I consider laterally weak or ambiguous were discarded. Yes, I read scientific papers. No, I do not always agree with their arrangement (or in some cases omission) of important data in peer-reviewed papers. Yes, I sometimes question their conclusions. In a clade that's still not well-understood. So pile the wood extra high. Meh. :XD:

Some of the clade terms I have defined for myself such that they are less vague or general and better describe or encompass what's "new" in each successively derived subclade.

It may not agree dogmatically with some of the published trees out there in the literature, and it does not include every published species (mainly unranked oddities such as Mongolosaurus, Austrosaurus, or the Nand Axis), however through side-by-side comparison of multiple elements of the skeletons of titanosauriforms, and comparisons of many papers, I have reached the conclusion that this is at least very close to how their evolution would have proceeded.
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:iconbricksmashtv:
bricksmashtv Featured By Owner Aug 29, 2016  Hobbyist Traditional Artist
I really like this tree. Do you have any plans to do a tree on the non-Somphospondyli Titanosauriformes (IE Brachiosaurids, Klamelisaurids, etc)?
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:iconpaleo-king:
Paleo-King Featured By Owner Sep 6, 2016  Professional Traditional Artist
That's the plan.
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:iconbricksmashtv:
bricksmashtv Featured By Owner Sep 6, 2016  Hobbyist Traditional Artist
Exciting! Can't wait to see it!
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:iconyutyrannus:
Yutyrannus Featured By Owner Jun 2, 2016  Hobbyist Traditional Artist
I noticed that you didn't put Sarmientosaurus or Magyarosaurus on here, why is that?
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:iconpaleo-king:
Paleo-King Featured By Owner Jun 3, 2016  Professional Traditional Artist
Didn't have the time, and Sarmientosaurus is a bit vague until I take a close look at the images and data. My best guess based on the teeth is a basal somphospondylian, those teeth are far too massive for a derived titanosaur. I woud put it near Paluxysaurus or Ligabuesaurus, and probably with a bigger nasal arch than depicted in the paper (the nasal bones are broken and missing and the skull has been somewhat crushed).

Magyarosaurus is a tough one, but is probably somewhere in lithostrotia.
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:iconbricksmashtv:
bricksmashtv Featured By Owner Jun 2, 2016  Hobbyist Traditional Artist
Or Elaltitan either
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 22, 2016  Hobbyist Traditional Artist
is it just me, or does Malarguesaurus being a Laurasiforme completely defeat the definition of the name (Forms from Laurasia) since Malarguesaurus is from Argentina (which is Gondwana).
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:iconpaleo-king:
Paleo-King Featured By Owner May 23, 2016  Professional Traditional Artist
It doesn't really defeat the purpose, seeing as Laurasiformes is just a name, coined earlier based on Laurasian somhpspondyls like Tastavinsaurus. Don't take a name too literally as being the definition of all members for all time. It's just a convenient label (and not a very descriptive one). We now know that most if not all titanosauriform families were on multiple continents. So it's not really "defeating the definition" since the founding members were indeed Laurasian. Just like not every nemegtosaur is from the Nemegt region (or even Mongolia in general) but the first ones discovered were.
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 23, 2016  Hobbyist Traditional Artist
Good point, it just feels strange.
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:iconornithopsis:
Ornithopsis Featured By Owner May 22, 2016  Hobbyist Traditional Artist
Laurasian forms is the etymology of the name, not the definition; there are loads of ironic names out there--my favorite is Saurolophinae ("lizard crest") for what are often called the crestless hadrosaurs.

I wouldn't bet too much on Malarguesaurus being a laurasiform, anyway, as titanosauriform phylogeny is still rather poorly understood.
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 22, 2016  Hobbyist Traditional Artist
Mine is Sigilmassasaurus brevicollis (the Short-necked Reptile from Sijilmassa, even though it's got the proportionally longest neck of Spinosaurs).

Well, we'll sort out this whole taxonomic mess one day. I'm certainly interested in a more complete description for this whole cladogram (maybe a paper?!).
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:iconornithopsis:
Ornithopsis Featured By Owner May 22, 2016  Hobbyist Traditional Artist
I agree. Titanosaur phylogeny is a mess, and it's definitely an area which needs as much research as possible. I'd love to see the dataset supporting this phylogeny published!
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:iconpaleo-king:
Paleo-King Featured By Owner May 23, 2016  Professional Traditional Artist
I'd love to. Unfortunately I have more immediate projects to work on, this tree has been in the works for a while as a personal project, not a commission. Best thing you can do is give me funding!!!! :XD:

That said my old phylogeny from 2011 is still on my computer. I would have to update it a LOT before trying to publish it these days. In the process I also discovered an interesting ratio in femoral features and proportions in determining the derivedness of titanosaurs, though with the exception that nemegtosaurs did converge on euhelopodids in some cases with regard to this ratio.
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:iconornithopsis:
Ornithopsis Featured By Owner May 22, 2016  Hobbyist Traditional Artist
You have several misplaced clade names on your cladogram; the clade you labeled "Osteodermata" is actually Lithostrotia, and Eutitanosauria should be either equivalent to Lithostrotia (your "Osteodermata") the clade comprising argyrosaurids+your "Lithostrotia", depending on whose definition of the clade you're using. Opisthocoelicaudiinae should include Aeolosaurini and "Isisaurinae". Euhelopodidae should include huabeisaurids.

I'm curious about several clades in your cladogram; what characters support Overosaurus+Pellegrinisaurus, Rocasaurus+Isisaurus, Jainosaurus+Yongjinglong, Baurutitan+Paludititan, and Alamosaurus as a nemegtosaurid?
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:iconpaleo-king:
Paleo-King Featured By Owner Edited May 23, 2016  Professional Traditional Artist
Welcome visitor! I don't believe we've been introduced before. You sound very incisive and curious so perhaps some clearing the air is in order.

Actually the clades are not misplaced. I put the names exactly where I intended them to be. I simply disagree with other people's definition of the clades. Many scientists do have a broader Lithostrotia, but in some cases it's so broad as to be paraphylectic or even nearly synonymous with titanosauria itself. In order for lithostrotia to actually mean something significant, specifically the derived skull, tail, and torso features associated with the saltasaur-like forms, it is necessary to categorize a bit more narrowly. And in reality the forms of armor found in basal Osteodermata (i.e. lognkosaurs and similar) are rather different than the forms found in true Lithostrotia like Laplatasaurus and Saltasaurus, which is truly lithostrotic in its skin (look up the meaning, the original Greek word itself has a rather bizarre history for a paleontological term). Also their morphologies are different enough that in my view Lithostrotia should be more specifically defined and the more general category of Osteodermata created for encompass all armored, caudally non-amphiplatyan and dorsally non-hypantrated titanosaurs, to include both Lithostrotia and their more basal non-lithostrotic armored cousins. Essentially it's a synonym for Upchurch's 2004 definition of Lithostrotia, which although monophyletic and thus far more scientific than some others, is nevertheless extremely broad and encompasses two very different armor types (one of which is not really lithostrotic at all) and also two morphologically rather different types of titanosaurs.

If you prefer to adhere to the more simplistic definitions commonly used in much of the literature, that's your call. I think more specific breakdown is needed rather than having all intermediate and derived titanosaurs lumped as unranked clades into Lithostrotia. It's currently FAR too large and vague for a category that is neither quite a family nor a superfamily. Sort of like how Gravisauria was invented to distinguish the Vulcanodontidae and Eusauropoda from more primitive sauropoda, but without Vulcanodontidae being merely an unranked clade in Eusauropoda or "basal sauropoda". So I stand by Osteodermata as a term I have defined for myself, to make Lithostrotia more descriptive. I know this is heresy for the ICZN... but honestly given how fast this still-murky area of sauropod taxonomy is changing, I am not bothered... I have lost a lot of respect for that unwieldy institution in the past few years. We use the earliest descriptions of groups and taxa for the sake of uniform reference standards, not  to make some sort of dogma from definitions that were written before many titanosaurs we know today were discovered or properly analyzed. Some folks just take all that is published at face value. I question it. That said, being an artist, and having a day job, AND compiling and submitting analyses for peer review is a tall order at this time. So I am focusing more on the art than the analysis. Though I hope to compile all my findings into a paper eventually. I have all the necessary source material and just as important, the photos.

Opisthocoelicaudiinae is a group whose breadth (pardon the pun) seems to wax and wane with every paper published. I would avoid putting Isisaurus in that group because it actually shares more morphologies with Saltasaurus. The scapula, caudals, and ilium are very Saltasaurus-like and nothing like Opisthocoelicaudia, and the tall neural spines and vertical neural arches are everything Opisthcoelicaudia is not. The latter feature is also not much like Saltasaurus or Neuquensaurus, and this animal is so unique in limb morphology it really needs its own group. It doesn't have a single opisthocoelous caudal either. I would also leave Aeolosaurini separate, though it is similar, due to their entirely different caudal morphology, at least until more complete specimens of its members are found.

Euhelopodidae may turn out to include Huabeisaurids. But that's a rather moot point since they are already so close anyway. I find them having some spinal differences with Euhelopus and Daxiatitan, and enough similarities with Phuwiangosaurus to perhaps be not quite in Euhelopodidae proper, but something closer to the branch node. Daxiatitan has some strongly procelous cudals, whereas with Huabeisaurus and "Xinghesaurus" they are all amphiplatyan or nearly amphiplatyan. In any case the two groups are so close it is hard to call either way.

As for characters:

Overosaurus+Pellegrinisaurus = the tail. caudal vertebrae morphs are a dead ringer.

 Rocasaurus+Isisaurus = the dorsals, particularly the laminae and the axial proportions. Also the hips.

Jainosaurus+Yongjinglong =
the scapula. The scap of Yongjinglong matches Jainosaurus more closely than Opisthocoelicaudia, especially the features on the trailing edge. The neck vertebra also looks just right to be there, a bit more derived than in Lognkosauria but not as derived as the Trigonosaurids.

Baurutitan+Paludititan =
the tail. The precise proportions and angles in the neural arch, neural spine, and prezygs is very close in these two. Closer than if you compare them with any other known titanosaur tails.

 
and Alamosaurus as a nemegtosaurid?.... overall proportions of the dorsal elements, features of the neural arches, the adult neck morphology, the hips.... definitely the hips. The hip proportions look closer to Rapetosaurus than to anything in Opisthocoelicaudiinae, where it's sometimes placed. And the femur as well. No hint of the extreme canting found in Opisthocoelicaudiinae. Plus Alamosaurus is a high-browser and its overall morphology fits very well with the known profiles of nemegtosaurids, not so well with squat tank-like Opisthocoelicaudiinae. Although there may end up being a member of Opisthocoelicaudiinae that was a tall-shouldered high browser, given that Isisaurus basically bucked the short, ground-feeder trend apparent in Saltasauridae as a whole.

BTW are you a watcher? I highly recommend it. The answers to many of your questions are in previous comments on my own work. I highly suggest being a watcher as then you will see the reasoning behind my perspectives. I am both a visual and a scientific thinker and I think the visual aspect is an aspect often lacking in the field and many of its compilations of cladistic data, which seem to ignore many significant characters and overemphasize obscure ones that either basal or convergent. Of course this goes back to "the tree is only as good as the different data and the realism of the weights you give them". At the end of the day this tree is as much to help me as anyone, since it is also based on a lot of my comparative reconstructions in preparing skeletals that are in the works. Knowing which animals are related to which is vital to filling in the gaps in incomplete specimens.

Of course purely non-diagnostic taxa, as well as those known from bad or conflicting photos, I have left out. Sonidosaurus was one such bitter disappointment, with the published description's rather good photos indicating something similar to Huabeisaurus or Phuwiangosaurus (though far too fragmentary to be 100% sure), but one of two contradictory sculpted mounts (and most internet sources) indicating it was a nemegtosaurid or similar, which I didn't see proof for in the rather gracile published images at all. This animal needs more research and probably a redescription.
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:iconornithopsis:
Ornithopsis Featured By Owner May 24, 2016  Hobbyist Traditional Artist
I do watch you, but I have not read through all of your posts, deviations, and comments (nor will I likely have the free time to do so in the near future), so my apologies if there is stuff I have missed.

Lithostrotia, Euhelopodidae, and Opisthocoelicaudiinae are all cladistically defined, and Lithostrotia in particular was created to include Malawisaurus. While I agree that "advanced titanosaurs" need a name, that name cannot be Lithostrotia.

Given the limited amount of published information on Pelligrinisaurus, I admit to a certain amount of lack of confidence in evaluating its relationships. However, I doubt it is a relative of OverosaurusPelligrinisaurus has a biconvex first caudal, as in Baurutitan, Alamosaurus, and Dreadnoughtus, but unlike the procoelous first caudal of Overosaurus and most titanosaurs. Unlike Overosaurus, Pellegrinisaurus has lateral pits on the anterior caudals and dorsoventrally compressed dorsal centra.

Rocasaurus is widely considered to be a saltasaurin. It shares several characters, such as dorsoventrally compressed caudals with a deep ventral fossa divided by a septum, uniquely with saltasaurins.

Yongjinglong is markedly more robust than Jainosaurus (based on the Chhota Simla radius), but an overall lack of overlap makes it hard to compare them. What scapular characters do they share? The angle between the dorsal/posteror margin of the acromion and the anterior/dorsal margin of the scapular blade looks to be close to 90 degrees in Yongjinglong and slightly obtuse in Jainosaurus, the anterior/dorsal margin of the blade appears straighter in Yongjinglong, and I don't see a prominent triceps longus tuberculum on Jainosaurus. Not sure what this says about their relationships, other than that I see no compelling synapomorphies between the two.

I don't see the similarity between Paludititan and Baurutitan. Paludititan has weakly anteriorly inclined, simple neural spines, whereas Baurutitan has more posteriorly inclined neural spines with well-developed laminae. Paludititan also has much smaller neural canals than Baurutitan, as well as having more closely-positioned haemal arch facets. In all of these characters, Baurutitan closely resembles Alamosaurus, a genus which it also resembles in having bulges dorsal to the transverse processes (seemingly absent in Paludititan), lateral bulges on mid-caudal haemal arches, and loss of transverse processes by caudal 10 (not preserved in Paludititan).

Dongbeititan
had a fairly long neck, so I doubt that the whole of Opisthocoelicaudiinae was characterized by squat, bulky, short-necked forms. Since the only nemegtosaurid Alamosaurus can currently be effectively compared to is Rapetosaurus, I'll focus there. Alamosaurus' coracoid foramen is located near the center of the coracoid, unlike the foramen in Rapetosaurus which is located on the scapulocoracoid suture. Rapetosaurus is also far more gracile than the massively-built Alamosaurus. The hips do look somewhat similar, but not remarkably so.

Based on the described Sonidosaurus material, what do you think it is? I agree that it does not seem particularly nemegtosaur-like, which makes me suspect that the mounts are in error. Its anteriorly directed transverse processes seemingly resemble Xianshanosaurus, if Mannion et al.'s LSDM codings are right for the latter genus.

What about Elaltitan? It's fairly well-described and known from somewhat decent material, but it's one of the few titanosaurs I can't find on this cladogram.
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:icondinolove453:
dinolove453 Featured By Owner May 22, 2016  Hobbyist Traditional Artist
*claps*
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:iconkrajax:
Krajax Featured By Owner May 22, 2016
I want to ask what analyses is your phylogenetic tree based on?
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:iconpaleo-king:
Paleo-King Featured By Owner Edited May 23, 2016  Professional Traditional Artist
It is based on comparative morphological analysis of the best available photos (unaltered) of all the overlapping material from these taxa, as well as a thorogh comparison of cladistic trees, their inclusivity of relevant visual data, etc. from among over 100 papers I have in my files. Literally too many to name them one by one right now.

It is not dogmatically based on any one analysis, but essentially takes the best and most consistent aspects of all of them (some of them are not very good admittedly and I do not agree with every part of every analysis that has been printed. Some of the ones coming out of China have been particularly crude and mistaken, though they are far from the only ones).  Also keep in mind that the more detailed papers often have multiple consensus trees, alternative positions for the taxon being analyzed, etc. based on bootstrap values and various other methods of logic, so there is no "final" conclusion even in more detailed papers like those of Upchurch.

I actually presented my own phylogenetic analysis at SVP 2011 in the abstract and poster on Ruyangosaurus (compiled the thing in Mesquite, great little program without the price-gouging of PAUP), though there weren't as many good specimens and taxa known then, and some of my findings were indeed off at the time - and I was also crunched for time. In 5 years we will look back again and see that some of my findings here were off too (though hopefully fewer this time around.) And there are some species which just continue to perplex everyone and no analysis will satisfy the whole field for them. Janenschia being a big one.

I have made this tree as much for my own use as for others, to aid in restoring incomplete species based on related animals. If parts of it seem "off" to you, please specify which species you are concerned about and I will be happy to answer.
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:iconstanleyrabbid:
StanleyRabbid Featured By Owner May 22, 2016  Hobbyist Traditional Artist
Wait, is this saying Sauroposeidon and Paluxysaurus aren't brachiosaurs?
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:iconpaleo-king:
Paleo-King Featured By Owner May 23, 2016  Professional Traditional Artist
Pretty much. The D'Emic paper busted their brachiosaur credentials with a lot more data than the description of Paluxysaurus had, and the added benefit a young Sauroposeidon for comparison and overlap. And not only that, taking a look at their shallower centra, wider hypantrum gaps, kinked femora, and oddly twisted (and interlocking) radii and ulnae, points to Sauroposeidon and Paluxysaurus being far more like Chubutisaurus than like any brachiosaurid.

Of course they superficially would still have looked a lot like brachiosaurs on the outside. Only that they weren't. Funny thing is not all Chubutisaurs had this appearance. Ligabuesaurus was a chubutisaur that may have anticipated Lognkosaurian neck proportions, i.e. really deep and thick. Its dorsal spines were also unusually tall. Still has the aforementioned defining chubutisaur features though.

I don't necessarily support D'Emic's second conclusion of Sauroposeidon being the same species as Paluxysaurus, however. For both the smaller Paluxysaurus specimen and the juvenile Sauroposeidon being of similar size range, they do show a number of differences in the bones that can not be pinned solely on ontogeny. Also the larger Paluxysaurus specimen looks to be at least subadult if not adult judging by the shoulder blade, and it's a lot smaller than the type specimen of Sauroposeidon. Like only half the size. And the cervical ribs of Paluxysaurus are pretty well-ossified at the ends, making it unlikely that it was another juvenile of Sauroposeidon. It was too mature in comparison to the Sauroposeidon juvenile from the Cloverly formation. Nevertheless they are closely related.
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:iconyutyrannus:
Yutyrannus Featured By Owner May 30, 2016  Hobbyist Traditional Artist
How possible would you say it is that Paluxysaurus is another species of Sauroposeidon? The size difference between different Palaeoloxodon species makes me think that could possibly be the case....
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:iconpaleo-king:
Paleo-King Featured By Owner May 31, 2016  Professional Traditional Artist
It's possible but the laminae and other features in similar-sized individuals lead me to question this.

Of course the problem with Paluxysaurus is that it's crushed, eroded, and distorted in so many ways. The juvenile Sauroposeidon material is in overall better shape. Some of the laminae and ends of processes are eroded pretty badly in Paluxysaurus so some comparisons are hard. We could be talking about two different genera here as well.

Paleoloxodon is an interesting case but with so many species all over the planet I think it's probably overlumped. At least they don't merge it with Elephas anymore... :XD:
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:iconyutyrannus:
Yutyrannus Featured By Owner May 31, 2016  Hobbyist Traditional Artist
Oh, okay. Funny, I always thought the Paluxysaurus material was better preserved than the Sauroposeidon juvenile material. Hopefully more remains will be discovered soon and settle this mystery.
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:iconpaleo-king:
Paleo-King Featured By Owner May 31, 2016  Professional Traditional Artist
Well if you download the Paleo-Electronica paper on Paluxysaurus, the color photos show how ugly the fossils are... most of them are a bit mangled. A couple cervicals are still in good shape. But it's just a beat up dinosaur extracted from ironstone or some other really hard rock. So it wasn't going to be a clean specimen no matter how precise they were. It had a lot of cracks that needed to be puttied.

The Sauroposeidon juvenile may have some broken parts but the intact parts at least are not so eroded and fractured/crushed.

There is already a good amount of remains, but you're right in one sense, we need more ADULT remains. Something from adult sauroposeidon besides just neck. That way we can see how ontogeny plays out long-term in these two animals.
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:iconyutyrannus:
Yutyrannus Featured By Owner May 31, 2016  Hobbyist Traditional Artist
Yeah, I hadn't seen the Paluxysaurus paper yet.

And better preserved Paluxysaurus remains as well.
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 22, 2016  Hobbyist Traditional Artist
Yeah, that's been generally accepted for a while (ever since D'Emic's analysis came out with that result in 2012). however, there are many of us who don't believe that Paluxysaurus is synonymous with Sauroposeidon as D'Emic suggests.
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 22, 2016  Hobbyist Traditional Artist
Wow, this is great. Really puts the whole tree into perspective. But one question: What's the Nand Axis?
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:iconornithopsis:
Ornithopsis Featured By Owner May 22, 2016  Hobbyist Traditional Artist
There's an isolated axis vertebra from the Nand region of India, which based on provenance probably belongs to either Jainosaurus or Isisaurus (neither of which has a known axis).
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 22, 2016  Hobbyist Traditional Artist
Ooh, exciting. I just found the paper earlier today. It was locked behind Elsevier's paywall (at least until I went to Sci-Hub ;) ).
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:iconpaleo-king:
Paleo-King Featured By Owner May 23, 2016  Professional Traditional Artist
The Nand Axis is undoubtedly a murky, nefarious and, it goes without saying, unpatriotic nuclear conspiracy, by nations so foul and deceptive that the original "Axis of Evil" left them out....

Wait, no, it's just a flippin' neck bone. Too much caffeine today. OOOOOOPS! :XD:
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:iconbricksmashtv:
bricksmashtv Featured By Owner May 23, 2016  Hobbyist Traditional Artist
:dignity-laugh:  It's a conspiracy, a bloody great big one! Illuminati cunfermed!

Yeah, too much caffeine will definitely do that to you.
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