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Re: "Elaphrosaurus" gautieri identified as an ......



Tim Williams wrote-

> Does the ulna bear a well-developed olecranon process?  This is referred
> material, so it may not have much bearing on the affinities of the
holotype.
> (You know how it goes with those Continental Intercalaire fossils...)

If only I knew.  Lapparents descriptions are anything but thorough.  He says
the bone was found isolated from the rest of the material, is 30 cm long,
and probably represents the ulna of this taxon.  No illustration or
anything.  Thirty centimeters is pretty long for an ulna when the humerus is
20 cm.  Perhaps the extra length is the olecranon, perhaps it has a weird
bird-like ulnohumeral ratio, perhaps the humeral length was underestimated,
perhaps it's from a larger individual, perhaps it's not even from "E.
gautieri.  So many possibilities.

> > The humerus, though missing its middle portion, is quite short (10 cm
> > wide proximally by 20 cm long).
>
> An obvious question, and I don't mean to sound facetious: if the middle
> portion is missing, how do you know how long/short the humerus is?

Good question.  Lapparent's again very brief, but the fact he would make
such a deal about how short and broad the humerus is indicates he had some
reason to believe it was that robust (especially since it was unheard of at
the time).  Perhaps they were found closely associated arranged as if the
middle section eroded away.  Perhaps the outline in lateral/medial view is
indicative.  Again, it's hard to know without more data.
Also, I made an error in my last post.  The proximal end of the tibia is
very expanded, not the distal end.  Specifically, the lateral condyle
projects away from the shaft quite a bit, and the medial condyle angles away
more.  The possible outline of where the astragalar ascending process would
be suggests it was laterally displaced, as seen in mononykines.

> _E. gautieri_ an alvarezsaur?  Very intriguing...

I thought so too, but there's really nothing else that even comes close to
the mix of characters seen in "E." gautieri.  I doubt "E." iguidiensis will
be as interesting.....

Mickey Mortimer