PROBLEM COELUROSAURS

[darren.naish@port.ac.uk]

I congratulate Mickey on the results of his study - it clearly involved a 
lot of work. A lot of the stuff there is great and makes sense, and 
obviously there may be other positions for some of the more poorly 
described or poorly known taxa (e.g., _Shanshanosaurus_ is likely to 
be an aublysodontine but you can't really tell this from the description 
(does _Shanshanosaurus have the unserrated premax teeth with a 
bilobed median ridge on the lingual face, as does _Aublysodon_/ 
_Stygivenator_)). Obviously my main take on the whole thing is - - 
how does the new coelurosaur I am working on fit into all of this?

As some of you know, this is the Wessex Formation (Wealden Group, 
Barremian) animal previously described in the popular press as a 'big 
cat dinosaur' (ugh) and variously dubbed _Gavinosaurus_ and 
_Lengosaurus_ (after Gavin Leng, who found it). Without giving too 
much away, I can say that it is a gracile, long-handed predator with 
elongate fused nasals and a premaxillary angle (sensu Britt) of about 
90 degrees. Various characters suggest an affinity with tyrannosaurids 
but the thing is not arctometatarsalian. One idea that needs a lot of 
thought is whether or not this is the same as _Nedcolbertia_ - 
unfortunately there is little overlapping material. The femur, distal 
tibia and pelvis are missing from our animal, dammit. And, BTW, what 
Nick L has been saying about trochanter homology in coelurosaurs 
makes me think that every identification I have ever made for a 
theropod trochanter is now probably wrong (see my paper in the next 
_Neues Jahrbuch_ to see what I mean).

Jim et al. say that _Nedcolbertia_ has a coracoid tuber, as does our 
animal (and so do ornithomimosaurs, apparently some individuals of 
_Allosaurus_ and birds), but unfortunately this element has not been 
figured for _Nedcolbertia_. In our animal, the coracoid is one of the 
coolest elements (IMHO). Manual unguals figured for _Nedcolbertia_ 
are weakly curved compared to those in our animal and I've previously 
used this as a feature that might differentiate the two (in my thesis). Of 
course, however, it's not impossible that such a character could be 
subject to ontogenetic or sexual variation.

Mickey mentioned _Stokesosaurus_, which he finds to be a basal 
coelurosaur. There is more material of this taxon awaiting publication. 


DARREN NAISH 
PALAEOBIOLOGY RESEARCH GROUP
School of Earth, Environmental & Physical Sciences
UNIVERSITY OF PORTSMOUTH
Burnaby Building
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