Rebbachisaurus gets a proper description

July 8, 2015

This just in: Wilson and Allain’s (2015) redescription of Rebbachisaurus garasbae, the type and only true species of Rebbachisaurus!

Wilson and Allain (2015:figure 3). Holotype of R. garasbae. Dorsal vertebra (MNHN-MRS 1958) in anterior (A), right lateral (B), posterior (C), and dorsal cross-sectional (D) views. Anterior faces top in D. Scale bar equals 20 cm.

Wilson and Allain (2015:figure 3). Holotype of R. garasbae. Dorsal vertebra (MNHN-MRS 1958) in anterior (A), right lateral (B), posterior (C), and dorsal cross-sectional (D) views. Anterior faces top in D. Scale bar equals 20 cm.

Here we see the much-admire’d dorsal vertebra that’s been on display for some time in the French National History Museum, and which we’ve seen here previously:

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

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

(It’s a shame that photo didn’t make it into the paper, really.)

There’s good and bad news here. The good news is obvious: this is a really important specimen, the type of a whole sauropod family, and it’s been in dire need of redescription because Lavocat’s (1954) paper did a bit of a drive-by on it. It’s great that there’s a proper description at last.

The bad news is, you can’t read it — at least, not unless you’re a JVP subscriber or at a wealthy university. It’s been a while, I think, since we wrote about a non-open access paper here at SV-POW!, and it’s funny how little we seem to have missed them. A lot of the action in vertebrate palaeo, especially for dinosaurs, seems to have moved to open access journals — especially PLOS ONE and PeerJ, but also of course the venerable Palaeontologia Electronica.

FIGURE 13. Holotype of R. garasbae. Right scapula (MNHN-MRS 1957) in medial (A) and lateral (B) views. Abbreviations: ac fo, acromial fossa; ac no, acromial notch; ac ri, acromial ridge; ss, origin of M. subscapularis. Inference of muscle attachment sites is based on comparisons with crocodile pectoral musculature (Meers, 2003). Reconstruction of distal margin of blade based on photograph of scapula in situ (Fig. 2A). Scale bar equals 20 cm.

Wilson and Allain (2015:figure 13). Holotype of R. garasbae. Right scapula (MNHN-MRS 1957) in medial (A) and lateral (B) views. Abbreviations: ac fo, acromial fossa; ac no, acromial notch; ac ri, acromial ridge; ss, origin of M. subscapularis. Inference of muscle attachment sites is based on comparisons with crocodile pectoral musculature (Meers, 2003). Reconstruction of distal margin of blade based on photograph of scapula in situ (Fig. 2A). Scale bar equals 20 cm.

It’s no secret that I am done with JVP (and Palaeontology, and the Journal of Paleontology, not that I’ve ever had a paper in that last one) until they become fully open access journals — and no, a hybrid OA option doesn’t cut it. I’m glad to have that notch on my bedpost, but I don’t feel any need to go back there.

But what I’d forgotten, or perhaps never really registered, is how terribly old-fashioned JVP papers look. No-one is disputing the journal’s high editorial standards or the importance of the work published there; but their tiny fonts, cumbersome two-column layout, and low-resolution black-and-white figures located bizarrely distant from the relevant text all make it feel like a journal badly in need of an overhaul for the 21st Century. I’m not sure what plans the Society has (it’s been years since I was a member) but I’d love to see JVP reinvented as a full-colour open-access journal, primarily online with printed copies only for those who want to pay for them. We’ll see.

Wilson and Allain (2015:figure 5). Holotype of R. garasbae. Computed tomography (CT) scans of the dorsal vertebra (MNHN-MRS 1958). A–E, transverse sections; F– G, frontal sections. Abbreviations: acpl, anterior centroparapophyseal lamina; cpol, centropostzygapophyseal lamina; cprf, centroprezygapophyseal fossa; ct, cotyle; lat. spol, lateral spinopostzygapophyseal lamina; med. cprl, medial centroprezygapophyseal lamina; med. spol; medial spinopostzyga- pophyseal lamina; nc, neural canal; pc, pleurocoel; pcdl, posterior centrodiapophyseal lamina; podl, postzygodiapophyseal lamina; posl, postspinal lamina; poz, postzygapophysis; prpl, prezygoparapophyseal lamina; prsl, prespinal lamina; prz, prezygapophysis; sc, subcamerae; spdl, spinodiapophy- seal lamina; se, septum; tpol, intrapostzygapophyseal lamina. Scale bar equals 10 cm for CT images.

Wilson and Allain (2015:figure 5). Holotype of R. garasbae. Computed tomography (CT) scans of the dorsal vertebra (MNHN-MRS 1958). A–E, transverse sections; F– G, frontal sections. Abbreviations: acpl, anterior centroparapophyseal lamina; cpol, centropostzygapophyseal lamina; cprf, centroprezygapophyseal fossa; ct, cotyle; lat. spol, lateral spinopostzygapophyseal lamina; med. cprl, medial centroprezygapophyseal lamina; med. spol; medial spinopostzygapophyseal lamina; nc, neural canal; pc, pleurocoel; pcdl, posterior centrodiapophyseal lamina; podl, postzygodiapophyseal lamina; posl, postspinal lamina; poz, postzygapophysis; prpl, prezygoparapophyseal lamina; prsl, prespinal lamina; prz, prezygapophysis; sc, subcamerae; spdl, spinodiapophyseal lamina; se, septum; tpol, intrapostzygapophyseal lamina. Scale bar equals 10 cm for CT images.

It’s great that Wilson and Allain had the Rebbachisaurus vertebrae CT-scanned, showing just how crazily lightly they are built: see figure 13, especially part A, above. But I have to admit to finding it strange that a 34-page paper that deals in detail with sauropod pneumaticity doesn’t cite anything by either Brooks Britt or our own Matt Wedel — surely the two people who have done the most important work in this area, certainly the most foundational work.

My 2009 paper (Taylor 2009, duh) does get a mention — not, this time, to disagree with me on the generic separation of Giraffatitan from Brachiosaurus, to but to acknowledge its recognition of the spinoparapophyseal lamina (SPPL) that occurs in D?8 of the Giraffatitan paralectotype MB.R.2181 (formerly HMN SII) and has now been recognised also in Rebbachisaurus.

Anyway, this is an important new paper, very well illustrated (apart from the annoyingly avoidable lack of colour) and with typically careful and exhaustive descriptions. It’s going to be very helpful, and it’s reawakened an idea that I once had …

… but that’s for another time.

References

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One Response to “Rebbachisaurus gets a proper description”


  1. […] that the new Wilson and Allain (2015) paper has redescribed Rebbachisaurus, we can use it to start thinking about some other specimens. Particularly helpful is this beautiful […]


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