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Re: Coelurus a maniraptoran (for how long?)



David Marjanovic wrote-

> Is this the same as
>
> > 18.  Wide vertebral foramen in thoracic vertebrae, vertebral
> > foramen/articular cranial facies ratio (vertical diameter) larger than
> > 0.40: absent (0), present (1).
>
> , and is it connected to the wide foramen magnum of *Shuvuuia*?

Yes, it's the same character.  It may very well be related the large foramen
magnum, as those theropods with wide foramen magnums (foramina magna?) (more
than 150% of occipital condyle width) also have tall vertebral foramina.
This includes Shuvuuia and ornithothoraceans.  Avimimus also has a wide
foramen magnum and tall neural canals.  However, Confuciusornis has a
foramen magnum of normal maniraptoran width and tall neural canals, so the
characters don't coincide exactly.

> Additionally, in *Eoalulavis* nearly only the keel is ossified.

Yes, I forgot about that one.  Eoalulavis has an incredibly narrow sternum
(width/length ratio 33%).

> "ulnar distal condyle present;"
> Is this the same as
>
> > 51.  Distal end of ulna subrectangular and transversely compressed (0),
or
> > subtriangular in shape (1).

Yes, you'll notice the full entry in the character list is-
"ulnar distal condyle: transversely compressed and craniocaudally extended
approximately at the same plane of humero-ulnar flexion-extension movement
(0); subtriangular shaped in distal view, with a dorsomedial condyle, and
twisted more than 54 degrees with respect to the proximal end (1)."

> Does anyone have an idea as to what a carpometacarpus is good for in
> flightless animals, and why only some pygostylians and alvarezsaurids have
> it?

So does Avimimus, though that doesn't answer your question.

> Is the famous book "Mesozoic Birds: Over the Heads of Dinosaurs" or
whatever
> its title was already published? Can someone give me the complete ref?

Not yet, I'm afraid.
L. M. Chiappe and L. Witmer, eds. Mesozoic Birds: Above the heads of
dinosaurs. Berkeley: University of California Press.

> What's the condition in oviraptorosaurs?

The symphysis extends for about half the pubic length in Caudipteryx,
Nomingia, Microvenator, Chirostenotes and oviraptorids.  This is the
primitive condition for coelurosaurs.

> "obturator process of ischium absent; terminal process[es?] of ischia not
in
> contact."
> True of *Mononykus*; oviraptorosaurs and segnosaurs have obturator
> processes; only the acetabular portion of the ischium is known for
> *Patagonykus*. Is an ischium of *Alvarezsaurus* known? And wasn't there an
> ornithothoracine whose ischia touched, or is this false memory?

No ischium is known for Alvarezsaurus.  Mononykines and pygostylians are
unique in lacking obturator processes, which is a good metornithine
synapomorphy.  Concornis has a proximoventrally placed process that Sanz et
al. (1995) interpret as an obturator process, but I think this looks more
like the "obturator process" of many birds that is a neomorph, not
homologous to the obturator process of other coelurosaurs.  Mononykines and
euornithines have distal ischia positioned far from each other.
Confuciusornis appears to be similar, although in Concornis they nearly
contact.  Rahonavis also has this derived condition.  Noguerornis (which I
know almost nothing about) has an ischial symphysis.  It's probably the
ornithothoracine you were thinking of.

> Does the sentence "A deep postspinal depression exists in each proximal
> caudal" refer to pneumatic fossae? (Depressions that look like pneumatic
> fossae are present on proximal caudal centra below the transverse
> processes.)

No, that's referring to the depression on the back of the base of the neural
spine, seen clearly in figure 7C.  However, the sentence "The centrum
exhibits an elongate excavation laterally" does refer to the lateral fossae
you are speaking of. :-)

Mickey Mortimer