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Re: Agustinia ligabuei



I wouldn't say that this instance typifies my experience with the rest
of the matrix (or, at least, the sections of it which I have
scrutinised so far); I shall report back when I'm done (which could be
a while and, I think, requires a trip to South America at some stage).
The number of taxa which I've been trying to code from the literature
(a dangerous undertaking I know, but I've used the codings of people
who have observed the specimens first hand when they're available)
that are poorly or incompletely figured is phenomenal. I've been so
glad to see redescriptions of *Argyrosaurus*, *Andesaurus*,
*Rayososaurus*, *Rocasaurus*, *Neuquensaurus* (at least the holotype
and appendicular elements), and whichéver others I've forgotten, come
out in the last few years.

On Wed, May 23, 2012 at 10:23 PM, Mickey Mortimer
<mickey_mortimer111@msn.com> wrote:
>
> Interesting idea that I unfortunately have no information on.  I did want to 
> say your experience with Curry Rogers' codings matches mine though, which is 
> a shame since its large number of taxa and characters had me excited 
> initially.
>
> Mickey Mortimer
>
> ----------------------------------------
>> Date: Wed, 23 May 2012 15:57:25 +0200
>> From: stephenfporopat@gmail.com
>> To: dinosaur@usc.edu
>> Subject: Agustinia ligabuei
>>
>> Hi all,
>>
>> I'm going to ask a potentially very silly question: how certain can we
>> be that the osteoderms (particularly types 3 and 4) of *Agustinia
>> ligabuei* Bonaparte, 1999 are actually osteoderms? Is it possible that
>> they are just misidentified transverse processes / sacral ribs
>> (compare the base of the osteoderm (but rotate it upside down) in
>> Bonaparte (1999) to Figure 23.B in Curry Rogers (2009), for example)?
>> If so, then the sacrum would have to have been at least a third wider
>> than it is long (though I don't 100% trust the scale bars for the
>> dimensions of the sacral vertebrae - in Bonaparte (1999), Figure 1
>> suggests that they are ~11cm long, whilst Figure 2 suggests ~67cm...).
>> Novas (2009) follows Bonaparte's (1999) Figure 2, and based on his
>> Figure 5.4 (p. 173; presuming his scaling of the osteoderms is
>> correct) the breadth of the pelvis (without the ilia) would be ~91cm.
>>
>> The identity of the Type 2 osteoderm (640mm transverse length) is a
>> bit more problematic; could it be the fused ischia, viewed dorsally?
>> Similarly problematic is the type 4 osteoderm in Figure 5 of Bonaparte
>> (1999) which was 760mm long; could this be a dorsal rib?
>>
>> The only images I am able to find of the holotype specimens are those
>> in the original paper and the rearranged images in Novas, 2009. The
>> discussions of Salgado & Bonaparte (2007) and Upchurch et al. (2004)
>> don't add much to the original description, the codings for
>> *Augustinia* [sic] in Curry Rogers 2005 appear not to actually
>> correspond to *Agustinia*, and I've had no luck finding any images on
>> the internet. Have I missed any important references to this specimen?
>> Do any photos and / or a quarry map exist somewhere, I wonder?
>>
>> If I'm completely off the track here, please let me know, it's just
>> that I've been looking at Bonaparte's figures and struggling to
>> believe the interpretation. This taxon is definitely in need of
>> redescription and re-illustration... or (wishfully thinking) another,
>> more complete specimen!
>>
>> Cheers,
>>
>> Steve
>>
>> Bonaparte, J.F., 1999. An armoured sauropod from the Aptian of
>> northern Patagonia, Argentina, In: Tomida, Y., Rich, T.H.,
>> Vickers-Rich, P. (Eds.), Second Gondwanan Dinosaur Symposium: National
>> Science Museum Monograph, 15, Tokyo, pp. 1-12.
>> Curry Rogers, K.A., 2005. Titanosauria: a phylogenetic overview, In:
>> Curry Rogers, K.A., Wilson, J.A. (Eds.), The Sauropods: Evolution and
>> Paleobiology. University of California Press, Berkeley, pp. 50-103.
>> Curry Rogers, K., 2009. The postcranial osteology of *Rapetosaurus
>> krausei* (Sauropoda: Titanosauria) from the Late Cretaceous of
>> Madagascar. Journal of Vertebrate Paleontology 29, 1046-1086.
>> Novas, F.E., 2009. Cretaceous sauropods, In: Novas, F.E. (Ed.), The
>> Age of Dinosaurs in South America. Indiana University Press,
>> Bloomington, pp. 166-241.
>> Salgado, L., Bonaparte, J.F., 2007. Sauropodomorpha, In: Gasparini,
>> Z., Salgado, L., Coria, R.A. (Eds.), Patagonian Mesozoic Reptiles.
>> Indiana University Press, Bloomington, pp. 188-228.
>> Upchurch, P., Barrett, P.M., Dodson, P., 2004. Sauropoda, In:
>> Weishampel, D.B., Dodson, P., Osmólska, H. (Eds.), The Dinosauria:
>> Second Edition. University of California Press, Berkeley, pp. 259-322.
>>
>> --
>> Dr. Stephen Poropat
>>
>> Postdoctoral Research Fellow
>> Uppsala University
>> Villavägen 16
>> SE-752 36 Uppsala
>> Sweden
>>
>> Research Associate
>> Australian Age of Dinosaurs
>> PO Box 408
>> Winton 4735
>> Australia
>



-- 
Dr. Stephen Poropat

Postdoctoral Research Fellow
Uppsala University
Villavägen 16
SE-752 36 Uppsala
Sweden

Research Associate
Australian Age of Dinosaurs
PO Box 408
Winton 4735
Australia