[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Leshansaurus qianweiensis, Cruxicheiros newmanorum and carnosaur allosauroids
it's nice to see that the greatest dinosaurs that ever lived (I mean
allosauroid carnosaurs, of course:o)) are given more space in
scientific papers than earlier. However, it seems like we (or at least
"I") overlooked a paper on a new carnosaur*, Leshansaurus
qianweiensis, that was published during the September in Acta
Geologica Sinica. The paper can be downloaded here:
[11,2 MB], but, unfortunately, it's written in Chinese so the only
thing you will probably understand are the figures (which could be
better) and some words in the text.
*Please, people, don't use the name "Allosauroidea" for the
branch-based clade containing everything more closely related to A.
fragilis than to [some coelurosaur]. There are reasons why it's not a
good idea. Mike Keesey already posted the link to the PhyloNom thread
here but I will do it once again:
Anyway, that's not everything I'd like to say. You all surely know
about the forthcoming paper on another new basal member of Tetanurae
(C. newmanorum) that is going to be published in the next issue of
Acta Palaeontologica Polonica. I know, of course, that it would be
more polite to wait for the paper (and discuss it when it's out) but
on the other hand, I really think that we all (or at least most of us)
read the paper already, and a few (me including) even tested its
phylogenetic position, so I will start with it and if you want to
continue, go ahead. I will appreciate it;o) If not, we can wait till
the paper is out...
First of all I'd like to say that I didn't modify Benson's (2009) +
Benson et al.'s (2009) data set very much. For my first "attempt" I
just corrected the two scorings for Monolophosaurus jiangi that Benson
& Radley (in press) mentioned in their paper, and C. newmanorum was
found as the most basal tetanuran. However, when I "ordered" some
characters (in the original paper all characters are "unordered"), C.
newmanorum was found deeply within Megalosauroidea (or Spinosauroidea,
if you wish), and some clades splitted up (nothing really drastic;
carnosaurs remained practically unchanged). Well, I have to add that
"my" results are not satisfactory for a few reasons: (1) I haven't
seen the material personally (so all I can do is just a work with
literature which - after some experiences - I don't find very
reliable) and (2) I've been pretty busy lately so I think that I
didn't do my best while I was working on it. For example, I think that
ordering characters may not be a good idea in a few cases (so some of
the characters that I "modified" are just "provisionally ordered" and
may in fact stay unordered). As for the analysis, I don't think that
three coelurosaurs is a sufficient number. Also, there is a lot of
taxa that could be added into the analysis (Shidaisaurus jinae,
Metriacanthosaurus parkeri, Yangchuanosaurus shangyouensis,
Saurophaganax maximus, Gasosaurus constructus, etc.)... But I wrote
more than I originally wanted... Basically, I just wanted to know if
the people who tested Benson et al.'s hypothesis modified somehow the
data set, and if yes, how did the tree topology change.
Your comments are very welcome!
Benson, R. B. J. 2009. A description of Megalosaurus bucklandii
(Dinosauria: Theropoda) from the Bathonian of the UK and the
relationships of Middle Jurassic theropods. Zoological Journal of the
Linnean Society (doi: 10.1111/j.1096-3642.2009.00569.x).
Benson, R. B. J., Carrano, M. T. & Brusatte, S. L. 2009. A new clade
of archaic large-bodied predatory dinosaurs (Theropoda: Allosauroidea)
that survived to the latest Mesozoic. Naturwissenschaften
Benson, R. B. J. & Radley, J. D. In press. A new large-bodied theropod
dinosaur from the Middle Jurassic of Warwickshire, United Kingdom.
Acta Palaeontologica Polonica.