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Re: Abydosaurus mcintoshi, a new sauropod from the Albian of Utah

On 25 February 2010 13:03, Thomas R. Holtz, Jr. <tholtz@umd.edu> wrote:
> Tim Williams wrote:
>> Mike Taylor <mike@indexdata.com> wrote:
>> The discovery of _Abydosaurus_ might actually have provided a good
>> opportunity to test the monophyly of _altithorax_+_brancai_.  Instead,
>> this monophyly was simply assumed by Chure &c, and _altithorax_+_brancai_
>> were therefore treated as a single OTU (_Brachiosaurus_) in the
>> phylogenetic analysis.
>> Also, as mentioned by Mike, _altithorax_ is from the Morrison, and
>> _brancai_ is from the Tendaguru.  Thus, I would have thought that lumping
>> the two into a single genus would require compelling morphological
>> evidence.  This isn't the case.  IMHO, Taylor (2009) established a strong
>> case for treating _brancai_ as a separate genus (_Giraffatitan_).  It's
>> only historical tradition that's holding the two together.  If Janensch
>> had *not* referred _brancai_ to _Brachiosaurus_, but had instead erected a
>> separate genus, we wouldn't be having this discussion.
> I would be seriously interested in seeing Lusotitan, Europasaurus,
> Sauroposeidon, Paluxysaurus, and Astrodon thrown into the mix!

There are at least two separate groups, on two different continents,
actively working on basal titanosauriform phylogeny right now --
possibly three if a long-delayed project is now off the ground.  And
that is not counting Paul Upchurch's in-progress super-giant analysis
of Sauropodomorpha, which is well larded with putative brachiosaurs.
It's an exciting time to be working on the world's greatest clade.

(NO, Tom, NOT Tyrannosauridae!)

> --
> Thomas R. Holtz, Jr.
> Email: tholtz@umd.edu   Phone: 301-405-4084
> Office: Centreville 1216
> Senior Lecturer, Vertebrate Paleontology
> Dept. of Geology, University of Maryland
> http://www.geol.umd.edu/~tholtz/
> Fax: 301-314-9661
> Faculty Director, Earth, Life & Time Program, College Park Scholars
> http://www.geol.umd.edu/~jmerck/eltsite/
> Faculty Director, Science & Global Change Program, College Park Scholars
> http://www.geol.umd.edu/sgc
> Fax: 301-314-9843
> Mailing Address:        Thomas R. Holtz, Jr.
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