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RE: Agustinia ligabuei
Here was my conclusion for the first 50 of her characters (in her thesis, which
I assume is the same as her publication), when I examined it back in 2005. 29
out of 50 characters survived, which is not the best ratio. Of course now that
we have Tapuiasaurus, maybe some of those characters that were autapomorphies
of Rapetosaurus would be useful. And maybe someone better versed in sauropods
than I was in 2005, or whose seen actual material, would have a different
1. Snout elongate.
2. Subnarial foramen inside narial fossa, not visible
3. Premaxillae taper smoothly posteriorly.
4. Nasal process of premaxilla projects at an angle of
<65 (1); <40 (2). (ordered)
Eu 55 Ca 75 Br 80 Ra 30 Ne ~30-35 Ma ~80 Martinez 55
5. Subnarial process absent.
6. Anterior margin of antorbital fenestra placed >70%
down maxillary length.
Ca 51 Br 76 Eu 62 Ra 21Ne ~53-68 Martinez 78
Coding of Nemegtosaurus contra Upchurch (1998).
9. Posterior maxillary process ends far dorsal to dental
10. Maxilla-nasal contact absent.
Correlates with 2.
12. Preantorbital fenestra absent.
13. Slit-shaped subnarial foramen.
Non-homologous, mix of 1 and 2.
15. DELETE. Apomorphy
16. Naris extends posteriorly far past anterior margin of
17. Naris faces dorsally.
19. DELETE. Apomorphy
20. Naris undivided.
21. DELETE. Apomorphy
22. Jugal contacts antorbital fenestra.
23. DELETE. Apomorphy
24. DELETE. No
difference noted between taxa.
Non-varying (Wilson, 2003).
26. Lacrimal angled >10 degrees posteriorly compared to
line drawn from ventral dental margin to ventral quadrate tip.
Ca 0 Eu 5 Br 5 Ne 15 Ra 25 Martinez 12
Correlates with 10.
28. DELETE. Apomorphy
Saltasaurus and Nemegtosaurus are coded differently by Wilson
(2003). Antarctosaurus has a suture as
33. Could not verify Camarasaurus, Brachiosaurus,
Nemegtosaurus or Quaseitosaurus.
34. Could not verify Ampelosaurus, Quaesitosaurus and Santa
35. Frontoparietal suture lower than frontal and parietal
midlines sutures (0); on same level (1); higher (2). (ordered)
38. Could not verify Ampelosaurus, Antarctosaurus,
Malawisaurus, Quaesitosaurus, Santa Rosa or Jabalpur.
39. Distance between supratemporal fenestrae twice their
width (0); subequal to their width (1); less than their width (2). (ordered)
40. Postparietal foramen.
41. Could not verify Jainosaurus, Malawisaurus,
Quaesitosaurus or Santa Rosa.
42. State 2 replaced with 1, as nothing exhibits state 1.
43. Could not verify Antarctosaurus, Santa Rosa or
45. Temporal bar at angle >10 degrees to tooth row (1);
>35 degrees (2). (ordered)
Ca 0 Br 30 Ra 40 Ne 55 Martinez 55 Qu ~50
46. Anterior process of quadratojugal concave
ventrally. Could not verify in
47. Quadratojugal process more than 130 degrees apart.
48. Squamosal-quadratojugal contact absent.
49. Anterior squamosal process reduced.
> Date: Wed, 23 May 2012 22:38:20 +0200
> From: firstname.lastname@example.org
> To: email@example.com
> CC: firstname.lastname@example.org
> Subject: 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
> <email@example.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: firstname.lastname@example.org
> >> To: email@example.com
> >> 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
> Research Associate
> Australian Age of Dinosaurs
> PO Box 408
> Winton 4735