Sauropod guru Jeff Wilson is on Twitter, as of a couple of weeks ago. In one of his earliest tweets, he showed the world this gorgeous photo of a Rebbachisaurus dorsal:

Jeff Wilson (left) and Ronan Allain (right), with dorsal vertebra of Rebbachisaurus.

Jeff Wilson (left) and Ronan Allain (right), with dorsal vertebra of Rebbachisaurus. Photograph by MNHN photographer, Copyright © Muséum National d’Histoire Natural.

I’m pretty certain this is the dorsal vertebra that’s been on exhibition in Paris for some time, and which is part of the holotype of Rebbachisaurus garasbae, which is in turn the type specimen of Rebbachisaurus and so of Rebbachisauridae as a whole. In which case it’s pretty darned important as defining a major group of sauropods.

This specimen was initially described, very briefly and without illustrations, by Lavocat (1954). The species (though a different specimen) was given a slightly better treatment by Russell (1996), as part of a larger work on isolated dinosaur bones. Russell included some line-drawings of the material (his figures 29-31), of which the pick is definitely this one of the bottom part of a dorsal vertebra:

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Rebbachisaurus garasbae, NMC 50844, anterior dorsal vertebra in (a) right lateral, (b) anterior, (c) left lateral and (d) posterior aspect. From Russell (1996:figure 30).

As noted by Russell (p388), this vertebra is similar, but not identical, to the one in Wilson’s photo. Russell says of his specimen that “the greater length of the centrum relative to the height and width of the intercentral articulations and less steeply projecting transverse processes imply that the vertebra occupied a more anterior position in the column.”

Will Rebbachisaurus ever get the detailed treatment that such gorgeous material deserves? Yes! here’s another tweet from Jeff:

Fantastic to think that Rebbachisaurus is in the works, and Nigersaurus to follow! Happy days!

References

  • Lavocat, R. 1954. Sur les Dinosauriens du continental intercalaire des Kem-Kem de la Daoura. [On the dinosaurs of the Continental Intercalaire of the Kem Kem of the Daoura].Comptes Rendus 19th Intenational Geological Congress 1952 (1):65-68. [English translation]
  • Russell, D.A. (1996). Isolated dinosaur bones from the Middle Cretaceous of the Tafilalt, Morocco. Museum Natl. d’Histoire Nat. (Paris) Bull. Ser. 4 18 (Section C, Nos. 2-3), 349-402.

Here is Tataouinea, named by Fanti et al. (2013) last week — the first sauropod to be named after a locality from Star Wars (though, sadly, that is accidental — the etymology refers to the Tataouine Governatorate of Tunisia).

FantiEtAl2013-tataouinea-fig3

Fanti et al. (2013: figure 3) T. hannibalis selected elements and reconstruction. (a) Sacral neural arches 1-3, right lateral view; (b) sacral neural spine 4, right lateral view; (c) sacral neural spine 5, right lateral view; (d) caudal vertebra 2 and fragment of caudal 1 postzygapophyses, left lateral view; (e) caudal vertebra 1, left lateral view; (f) sacral centrum 1, ventral view; (g) sacral centra 2-5, ventral view; (h-j) caudal vertebra 3, anterior (h), left lateral (i), posterior (j) views; (k) left ilium, lateral view; (l) right ischium, medial view; and (m) skeletal reconstruction of T. hannibalis. Missing elements based on other nigersaurines. Scale bar: 10 cm (a-l), 1 m (m). a, acetabulum; f, fossa; hr, hyposphenal ridge; ip, ischial peduncle; ll, lateral lamina; pf, pneumatic foramen; pl, pleurocoel; poz, postzygapophysis; pp, pubic peduncle; psdf, prezygospinodiapophyseal foramen; sdl, spinodiapophyseal lamina; spol, spinopostzygapophyseal lamina; spzl, spinoprezygapophyseal lamina; sr, sacral rib; tp, transverse process. The asterisk indicates the fossa bounded by the spzl and the sdl.

No doubt Matt willl have much more to say about this animal, and especially its pneumatic features. I just thought it was time for a picture-of-the-week post.

UPDATE: Matt here, just a few quick thoughts (I’m in the middle of my summer anatomy lectures so they will be less extensive than this animal deserves). First, it’s awesome to see so much pneumaticity, and in elements that have not previously been reported as pneumatic in sauropods. The authors make a good case that we’re looking at actual pneumaticity here, for example in the pelvic elements, and not something else. So that’s cool.

What’s even cooler is that we’re seeing this in a diplodocoid:  Tataouinea is a rebbachisaurid. We’ve seen extreme pneumaticity in saltasaurines, and now we’ve got a parallel evolution of this character complex in diplodocoids. That’s cool by itself, and it’s further evidence that the underlying generating mechanism–the air sacs and their diverticula–were all in place long before they started leaving traces on the skeleton. The case for a birdlike lung-air sac system in sauropods, in saurischians, and in ornithodirans generally only keeps getting stronger. That is, we’re seeing more evidence not just that air sacs were there, but that they were bird-like in their layout, e.g., pneumatization of the pectoral girdle by clavicular air sacs, in both saltasaurines and theropods (avian and otherwise), and now extensive pelvic pneumatization (i.e., going beyond what we’ve seen previously in saltasaurines) by abdominal air sacs in rebbachisaurids and theropods (and pterosaurs, can’t forget about them). Happy times.

Reference

Fanti, Federico, Andrea Cau, Mohsen Hassine and Michela Contessi. 9 July 2013. A new sauropod dinosaur from the Early Cretaceous of Tunisia with extreme avian-like pneumatization. Nature Communications 4:2080. doi:10.1038/ncomms3080

Just a quick note that my article Academic publishers have become the enemies of science is now up on the Guardian’s Science Blog.  Spread the word!

(You’re welcome to comment here, of course, but if you post your comments on the Guardian site, they will be much more widely read.  Registration is very quick and free.)

Rebbachisauridae incertae sedis MMCH-Pv 49, anterior cervical vertebra (MMCH-Pv 49/11) in right lateral (reversed) and anterior views (Haluza et al. 2012:fig 2A-B)

Here at SV-POW! Towers, we have often lamented that so much dinosaur research is locked up behind the paywalls of big for-profit commercial publishers, and that even work that’s been funded by public money is often not available to the public.

One of the quiet delights of the last couple of years has been watching the hide-research-from-researchers edifice slowly crumbling, and indeed we have a whole section of the site dedicated to that very thing: the Shiny Digital Future.  The process is slow, which should surprise nobody given that large, powerful, profit-motivated corporations are trying to prevent it, but it does feel increasingly inevitable.

This week has brought two more steps towards the open-access utopia: one of them specific and immediate, the other more long term but potentially much more far-reaching.

  • In the immediate, the New Mexico Museum of Natural History has made all issues of its Bulletin up to 2008 freely available.  Although the quality of the articles in these issues is hugely variable, there is a lot of good and important stuff in there, and it’s a boon to the community that they are now open to anyone who wants to read them.
  • I just heard today about the Federal Research Public Access Act (HR 5037), brought before Congress six days ago by a bipartisan group of six representatives (four Democrats and two Republicans).  If passed it would ensure that all research funded by eleven U.S. federal agencies was made open-access.  If you’re American, follow the link to see what you do to help ensure that it’s passed!

As Galadriel said, the world is changing.

Holotype dorsal vertebra of Nopcsaspondylus, apparently, from Mannion (2010:fig. 5), although it bears little resemblance to Apesteguia (2007:fig. 2) which is the illustration of that element in the paper that named the genus. Mannion's figure seems to be reproduced from Nopcsa (1902), which I really ought to get hold of so I can check this for myself. Ever notice how Haplocanthosaurusy rebbachisaurid dorsals look? Just sayin', is all.

Finally: I know that whenever we talk about proprietary publishers, I always tell people to go and read Scott Aaronson’s essay on the subject, but seriously: if you’ve not read it before, go and read it now.  It’s brilliant.

Update (22 April 2010)

Thanks to Phil for the clarification below on whether the pictured vertebra is or is not the Nopcsaspondylus holotype (it is).  Phil also sent me a scan of Nopcsa’s original figure of this plate, which is rather better than the reduced version that made it into the new paper, so here it is!

Definitely the holotype dorsal vertebra of Nopcsasopondylus, from Nopcsa (1902). Still looking kind of Haplocanthosaurusy. The main differences apparent here seem to be that this vertebra has a more vertically compressed centrum and more medially directed SPOLs than the Haplo dorsals. Still, I find myself wondering how many steps it would take to move Haplo into a basal rebbachisaurid position. Funny, really, Rebbachisauridae is just about the only sauropod clade that it hasn't been referred to.

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