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RE: Talluscoatum and Maniraptoran Tyrannosaurs

My response to Dr. Holtz: (his text is preceded by ">>")
>>Maniraptora suffers from "too many definitions syndrome" anyway.  Gauthier was explicit >>in his original definition in 1986: its modern birds and all taxa closer to them than to >>ornithomimosaurs.  My 1994 "redefinition" was unwarrented: hence the creation in 1996 of >>Maniraptoriformes.  Sereno's 1997/1998 "redefinition" (modern birds + Oviraptor) is >>equally unwarrented.
>>In other words, you cite a small handful of features that support your hypothesis, but do >>not deal with those which refute it (although, to be fair, you do deal with the absence of the >>hyperextendable toe in tyrannosaurs (where it is most assuredly NOT present!!!!).
There is a large number of reasons I'm still working on (the arctometatarsus, hindlimb modification, etc.), that's why I wrote: "Yes, I know it needs work and probably should be revised."
>>Of minor note, Vorona was established as a much more derived bird than the >>archaeopterygids, so other than their co-occurrance in the same quarry there is little shared >>between them among the birds.
I guess it should return to the Ornithothoraces where I found it from.
>>I am interested in your reasons for placing Microvenator in Elmisauridae (more properly >>Caenagnathidae).
Microvenator is a possible member of the Elmisauridae which is what I seem to pick up from other dinosaur sites. Caenagnathus is not a valid taxa whereas Elmisaurus is therefore the clade should be renamed to fit valid internal members.
>>If you popped the tyrannosauroids and coelurid-grade forms out of there, I'd largerly >>agree with the details.  However, I think that troodontids would definitely be up in there.
About the "coelurid-grade forms",  do you mean the ornitholestids and Coelurus?  I'm still working on the troodontids (actually, I forgot to put them in the when I wrote my post).  They could be dromaeosauroids, birds (?), arctometatarsalians or "enigmosaurs".  Personally, I think they may be somewhere between birds and dromeys.
>>Ummmm...  Gee, I wish I had thought of that... :-)  (Holtz, 1994).
In response, I never read that paper because at the time because third graders don't have access to technical papers (they also don't know about technical papers).  Also I didn't say my idea was original, I just said what my conclusions were.  And my conclusions were based on the work of others.  Besides, I didn't claim I thought of it first just that it was what I think about it.
>>You are mistaken about the wrist morphology of ornithomimosaurs.  Their carpals are >>NOT re-expanded: they are instead reduced relative to the condition in typical theropods >>OR more derived maniraptorans.
I just meant that...No wait, I'm confused and mistaken.  And you are right on that.  I guess working in a museum and being a professional paleontologist gives you access to stuff I only can find in books or on the internet.
  |--"Enigmosauria" Keesey, unofficial
  |  |--Oviraptorosauria
  |  |  |?-Caudipteryx
  |  |  `--+--Avimimidae
  |  |     `--Oviraptoroidea
  |  |        |--Elmisauridae
  |  |        |  `--+?-Microvenator
  |  |        |     `--(others)
  |  |        `--Oviraptoridae (sensu J.A. Headden, DML)
  |  `--Therizinosauria
  |     |?-Beipiaosaurus
  |     `--Therizinosauroidea
  |        |?-Alxasaurus
  |        `--Therizinosauridae
  |           |?-Nothronychus
  |           |--Segnosaurinae (?=Enigmosaurinae)
  |           |  |--Enigmosaurus
  |           |  |--Erlikosaurus
  |           |  `--Segnosaurus
  |           `--Therizinosaurinae
  |              |--Nanshiungosaurus
  |              `--Therizinosaurus
     |  |--"Archaeornithoidinae"
     |  |  |--Archaeornithoides
     |  |  `--Byronosaurus
     |  `--Troodontinae
     |     `--+--(others)
        |  |?-Alvarezsauridae
        |  `---->Pygostylia
        `--Dromaeosauroidea (implied Matthew & Brown, 1922)
There for now, I hold this view but I don't know what to do with everyone coelurosaurs, especially the dryptosaurids, coelurans, ornitholestids, compsognathids, tyrannosaurs and ornithomimosaurs.  I think Sereno's Tyrannoraptora might be reworkable...
Just one last thing, though...  WHAT ABOUT TALLUSCOATUM?  No one seems to want to talk about it...
Nicholas Gardner
The Dinosaur Homepage

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