RE: Neuquenraptor argentinus

[Tim Williams <twilliams_alpha@hotmail.com>]

Some other interesting tidbits...

_Hulsanpes_ is given as a "derived dromaeosaurid".  (There had been murmurs 
that this maniraptoran might be a bird.  Looks like it's back in with the 
dromies.)

_Unquillosaurus_ is not mentioned explicitly, but it is referenced by Novas 
and Pol with respect to "bizarre representatives [of Maniraptora] of large 
size".  Earlier, Novas and Agnolin (2004) call _Unquillosaurus_ a "giant 
maniraptoran".  However, my back-of-the-envelope calculations give an 
estimated body length of 4m for _Unquillosaurus_.  This is based on the 
length of the pubis (c.50 cm), which is all we have to go on.  Relatively 
speaking, 4m really isn't very big for a theropod - especially considering 
that we have alvarezsaurids and dromaeosaurids that were at least that 
large.  And therizinosauroids were typically larger, and no doubt much 
heavier.

The arctometarsalian foot of _Neuquenraptor_ and troodontids implies that 
derived dromaeosaurids lost this trait.  I wonder why?  As Jeff Hecht 
mentions in the _New Scientist_ article, dromies like _Velociraptor_ might 
have been less speedy than their arctomet counterparts.

Also note that the dromaeosaur was found "while digging up the rib cage of a 
titanosaurid sauropod".  Coincidence?  Or was the poor titanosaur the 
predator's last meal?

I might be wrong here, but I believe that _Neuquenraptor_ is the first 
direct evidence of a South American theropod that has an enlarged 
sickle-claw on its foot (the second toe, as in other paravians).  We lack 
the right pedal material for _Unquillosaurus_ and _Unenlagia_ to determine 
if these guys had sickle-claws; the enlarged sickle-claw of _Megaraptor_ 
appears to come from the hand, not the foot (based on new material); and 
that of _Noasaurus_ is open to doubt based on comparisons with related taxa 
(especially _Masiakosaurus_).


Tim