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Re: Anatomical details
David Marjanovic wrote-
> - Does *Hesperornis* have a pygostyle? Is the end of the tail known at
Yes. Clarke (2002) says it's approximately two caudals in length.
> - Behind the transition point, most theropods have broad, forward-leaning
> prezygapophyses that stiffen the tail. Some (*Archaeopteryx*, *Rahonavis*)
> have narrow prezygapophyses that do the same. Dromaeosaurs have both pre-
> and postzygapophyses elongated beyond good and evil, and the chevrons,
> Scansoriopterygids... *Epidendrosaurus* is not well enough preserved.
> *Scansoriopteryx*, however... its chevrons are plesiomorphic; but are its
> pre- and postzygapophyses discernible in the first place? In the photos
> are seemingly not. I can't tell if only the prezygapophyses are lengthened
> (as the very optimistic drawings show it) or the postzygapophyses, too. I
> remember some fellow listmembers have seen the specimen...?
I find the caudal prezygapophyses quite visible in figure 13 of Czerkas and
Yuan (2002). They are about 50-60% of the previous centrum's length.
Similarly, the postzygapophyses seem to extend to the tip of the preceding
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html