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Re: "Ichabodcraniosaurus" and NGMC 91



Mark Norell wrote-

> > 1) "ichabodcranosaurus" was referred to in passing in Mike Novacek's
> > first book.  This reference refers to an as yet unnamed dromaeosaur
> > skeleton collected at Khulsan and figured (fig. 24) in Norell and
> > Makovicky 1999- Important features of the dromaeosaurid skeleton II.
> > It is Novitates # 3282. The specimen number is IGM 100/980.  The name
> > comes from how pissed off Perle and I  were after spending days
> > excavating it in bad sandstorm conditions only to find out that while
> > most of the skeleton was there up to the axis/atlas it had no head.
> > The skull has never been discovered.  I think what people are
> > referring to is another unnamed dromaseosaur, known only from a skull
> > and a few cervicals, from Ukhaa Tolgod (IGM 100/1015) which is on the
> > cover of Discovering Dinosaurs 2nd edition.  This animal will have a
> > name in the next few months.

Interesting.  Gotta love being subject to misinformation.  Sorry about that.
The photographed portion of "Ichobodcraniosaurus" is very similar to
Velociraptor, but I'll have to look at it more closely in the future.  Seems
there are characters in IGM 100/1015 that do indicate it's a new taxon, not
just Velociraptor.  I await reading that paper.

> > We could have easily found minutiae that would have allowed
> > us to designate NGMC 91 as a new taxon.  It would have been in our
> > best interest to do so.  However, it does none of us any good to
> > recognize yet another bad type specimen.  If we were into this game
> > we could have a press conference every few months naming new poorly
> > preserved rubble dinosaurs from the Gobi and China.  These animals
> > are diagnosable, they are on my desk and in my cabinets, I just don't
> > see how it helps us to name them.

This is confusing to me.  Assuming a taxon is diagnostic, aren't we expected
to name it?  As long as there isn't a good possibility of it being
diagnosable due to ontogenetic/pathological/ individual variation, I don't
see the problem.  Even if it's poorly preserved, naming and describing
diagnostic organisms is one of the main goals of biology, is it not?

> > 6) A comprehensive analysis of coelurosaurs that includes microraptor
> > will appear soon.  The data matrix will be available at
> > http://research.amnh.org/users/norell/TWGhome.html          Along
> > with our other matrices.  The links go live coincident with
> > publication.  The sinovenator  matrix will be up early next week.
> > Errors and reinterpretation always exist- in comment it is best to
> > restrict it to the most recent iteration of our matrix.  All
> > comments, corrections etc. are appreciated.

That's a great idea!  I look forward to utilizing these resources.

> > 7) The classification issues that are coming up all of the time about
> > whether microraptor is a dromaeosurid or sinovenator is a troodontid
> > are naïive.  It does not matter what you call these animals  and many
> > of us are adverse to using any formal names for higher taxa.  Current
> > phylogentic hypotheses show that microraptor is more closely related
> > to sinornithosaurus, velociraptor, deinonychus, etc. than it is to
> > anything else. Sinovenator is likewise more closely related to
> > Ttroodon, byronosaurus and saurornithoides, etc. than it is to
> > anything else.

Adverse to using formal names for higher taxa?!  Can't say I like that idea.
I think the issues arising with regards to Microraptor and Sinovenator are
due to disagreements as to it's phylogenetic placement, not subjective
issues such as if the concept of Dromaeosauridae or Troodontidae should
extend to them.  For instance, I think there's a good possibility
Microraptor is more closely related to neornithines than to Dromaeosaurus,
and may even be an avian.  Thus, I would dispute calling it a dromaeosaurid.
I don't see how such issues are naive.

Mickey Mortimer