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Nanningosaurus (was Re: Planet of the New Papers)



>
> Mo, J., Zhao, Z., Wang, W., and Xu, X. 2007. The first hadrosaurid dinosaur
> from southern China. Acta Geologica Sinica (English Edition) 81(4):550-554.
>
> ABSTRACT: A new hadrosaurid dinosaur, Nanningosaurus dashiensis gen. et sp.
> nov., is described based on an incomplete skeleton from the Late Cretaceous
> red beds of the Nalong Basin, Guangxi, southern China. Diagnostic features
> for the new taxon include the presence of a tall and sharply peaked dorsal
> process of the maxilla with reduced process of the jugal and a distinct
> lacrimal facet, gracile humerus with low, rounded deltopectoral crest,
> mandibular condyle of the quadrate transversly broad with reduced
> paraquadrate notch, dentary tooth with sinuous median carina and subsidiary
> ridge, relatively few tooth positions, ischial shaft straight along most of
> its distance, but to curve dorsally and expand at the distal end before the
> ischial foot begins. Phylogenetic analysis suggests that Nanningosaurus
> dashiensis is a basal member of Lambeosaurinae.
>

A week later, I finally got the chance to sit down and score
Nanningosaurus into Evans and Reisz's dataset. The results were 3
MPTs, TL 121, CI 0.835, RI 0.878
3 MPTs, 121 steps, CI- 0.834, RI 0.878
--+--Probactrosaurus
   |--Telmatosaurus
   `--+--Gryposaurus
       `--+--Aralosaurus
          `--+--Nanningosaurus
              `--+--Tsintaosaurus
                  `--+--Jaxartosaurus
                     `--+--Amurosaurus
                         `--+--+--Charonosaurus
                             |  `--Parasaurolophus
                             `--+--Nipponosaurus
                                 `--+--Lambeosaurus
                                     `--+--Olorotitan
                                         |--Corythosaurus
                                         `--Hypacrosaurus

Topology does not vary from that of the original authors (Evans and
Reisz), except for the presence of Nanningosaurus between Aralosaurus
and Tsintaosaurus. This does not conflict with the topology found by
Mo et al. given that they had scored Nanningosaurus into Horner et
al.'s dataset which I suspect was completed and submitted to the
reviewers for the Dinosauria II long before most of the recent
publications came out on Amurosaurus, Aralosaurus, Charonosaurus,
Olorotitan and so on. I'm being tolerably nice this evening and
cutting them some slack based on their dataset choice. Obviously, it'd
have been nice if they'd included it in something a little more
inclusive, such as Prieto-Marquez's work (which is a little bit better
than Horner et al.'s in some aspects), or a composite effort from
several different sources, or at the very least, scored in those
additional lambeosaurines. Horner et al.'s dataset is fairly
expansive, but seems to suffer from a bad case of "Amero-centrism",
largely ignoring a great deal of non-NAm taxa (I do believe what I
suggested earlier is the cause of this though).

As I get more time, I'll keep poking into this, I suppose.

Only 20.2% of the total characters were able to be scored-
'Nanningosaurus dashiensis'         ?????????? ????????11 011???????
?????????? ???????1?1 ?????11??0 000??????0 ??????01?? ????????11 1???

Nick
http://www.alkalyze.net/nick.html


Evans, D.C. and Reisz, R. R. (2007). Anatomy and relationships of
Lambeosaurus magnicristatus, a crested hadrosaurid dinosaur
(Ornithischia) from the Dinosaur Park Formation, Alberta. Journal of
Vertebrate Paleontology 27 (2): 373-393.
Horner, J.R., Weishampel, D.B. and Forster, C.A. (2004).
Hadrosauridae. Pp. 438-463 in The Dinosauria, 2nd ed., D. B.
Weishampel, P. Dodson and H. Osmólska (eds.). University of California
Press, Berkeley.
Mo, J., Zhao, Z., Wang, W. and Xu, X. (2007). The First Hadrosaurid
Dinosaur from Southern China. Acta Geologica Sinica 81 (4): 550-554.
Prieto-Marquez, Gaete, Rivas, Galobart and Boada (2006). Hadrosauroid
dinosaurs from the Late Cretaceous of Spain: Pararhabdodon isonensis
revisited and Koutalisaurus kohlerorum, gen. et sp. nov. Journal of
Vertebrate Paleontology 26(4): 929-943.