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New Refs.

Dear Listmembers for those of you (the most on the List) that are
interesting on Tetanuran-Theropods I think that this is a new refs, because
I don't have see it before.
_Rauhut O.W.M. 2004 Braincase structure of the Middle Jurassic theropod
dinosaur Piatnitzkysaurus. Canadian Journal Earth Science 41(9)
Follow the abstract:
The braincase of the Middle Jurassic basal tetanuran theropod
Piatnitzkysaurus floresi is described in detail. It exhibits several
probable autapomorphic characters of this taxon, including the extremely
shortened and narrow basipterygoid processes, the presence of parasphenoid
recesses that seem to communicate with each other, and basipterygoid
recesses that are approximately as long anteroposteriorly as they are high.
The braincase of Piatnitzkysaurus shows two possible synapomorphies with the
enigmatic European Middle Jurassic theropod Piveteausaurus, a subrectangular
pituitary fossa that is wider than high and the transverse span between the
basipterygoid processes being smaller than the width of the basal tubera. A
noteworthy aspect of the braincase of Piatnitzkysaurus is the high number of
accessory pneumatic recesses, which indicates that the presence of an
anterior and dorsal tympanic recess, and possibly also of subcondylar and
basipterygoid recesses is plesiomorphic for tetanurans. In contrast, the
bones enclosing the brain (e.g., laterosphenoid, prootic, supraoccipital)
are very massive and lack internal pneumatic chambers, as they are present
in later tetanurans.

Alessandro Marisa
Via A. grandi n.18
email: amaris@tin.it
or: iguanodontia@yahoo.it