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Re: Details on SVP Thursday posters (Part 2)



 
Bertini and Franco-Rosas, 2001. Scanning electron microscope analysis on Maniraptoriformes teeth from the Upper Cretaceous of Southeastern Brazil. JVP 21(3) 33A.
Over two-hundred teeth from the Bauru Group (Adamantina and Marilia Formations) of Brazil were examined and found to belong to dromaeosaurids (including velociraptorines), troodontids, Richardoestesia gilmorei and four new taxonomic groups.
Now that sounds promising...
Gishlick, 2001. Evidence for muscular control of avian style automatic extension and flexion of the manus in the forearm of maniraptors. JVP 21(3) 54A.
Three muscles are involved with the coordinated folding of the forearm and metacarpus in birds- m. extensor metacarpi radialis (EMR), m. flexor metacarpi ulnaris (FMU) and m. extensor metacarpi ulnaris (EMU).  These insert in a particular way in birds to allow "two joint" muscles that can automatically flex and extend.  Caudipteryx, Deinonychus, Velociraptor and Archaeopteryx are shown to have osteological correlates for these insertions, showing they had an avian-like wing-folding mechanism.
Did they mention something that does not have the... character? :-)
Leshchinskiy, Voronkevich, Fayngertz, Maschenko, Lopatin and Averianov, 2001. Early Cretaceous vertebrate locality Shestakovo, Western Siberia, Russia: A refugium for Jurassic relicts? JVP 21(3) 73A.
The title refers to the fact that tritylodontid almost-mammals have been identified from there. Before the discovery of EK tritylodontids in Japan in IIRC 1998 tritylodontids were supposed to have died out in the MJ.
 
Thanks for the information on the two characters I suggested (and for showing how my peculiar memory works). :-)
 
Next characters:
 
Pubis not (0) smoothly convex over its entire length including the foot/boot (1). Present in Allosaurus fragilis sensu PDW, not too robust tyrannosaurids, oviraptorids, Nomingia (to an enormous extent) and Caudipteryx (pers. obs.), not present in non-coelurosaurs except A. fragilis, dromaeosaurs, Archaeopteryx, Rahonavis and Avimimus. Allosaurs and tyrannosaurs have greatly enlarged the pubic peduncles and the corresponding proximal ends of the pubes, unlike oviraptorosaurs. Maybe this retrieves Oviraptorosauria...
 
I also need something that ties Sinornithosaurus, Microraptor and preferably Archaeopteryx to the (Bambiraptor + Dromaeosauridae) clade. Judging from the dorsal views in PDW, the plesiomorphy (coelophysids, allosaurs, tyrannosaurs...) is that the ilia are more or less parallel to the sacral neural spines and quite close to them, while Archaeopteryx and dromaeosaurids have the ilia far apart (the sacral transverse processes + ribs are longer than the transverse processes of the caudals and apparently the dorsals) and Avimimus has them close together cranially and far apart caudally, which is said to be birdlike (true for Neornithes, pers. obs.). What have I overlooked this time?
 
Could someone comment on the upturned nasals/depressed snout as a synapomorphy for (Archaeopteryx + Dromaeosauridae), or what else I could take from http://www.dinosauria.com/jdp/archie/dromey.htm to get some more resolution?
 
Thanks in advance.