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COELOPHYSOIDS & CARCHARODONTOSAURS



I recently said that coelophysoids do not have a fibular crest on the 
tibia, and that this might therefore be a shared derived character of 
Neoceratosauria + Tetanurae. This does not seem to be correct.

Padian, in his redescription of the type material for _Coelophysis_, 
figures and describes a fibular crest. I know that this material 
probably does not belong to the same taxon as the GRT, but it is 
still a coelophysoid so far as I know. I do not have Welles' (1984) 
on _Dilophosaurus_ to hand, but the diagrams in Rowe and Gauthier 
(1990) of the dilophosaur tibiae do have a ridge that appears to be a 
fibular crest.

Gauthier (1986) used fibular crest as a theropodan synapomorphy, but 
outside of Tetanurae he only said that it was present in 
_Liliensternus_ and _Procompsognathus_. In Ostrom (1981), the 
_Procompsognathus_ tibiae are such a mess it's hard to make sense of 
them, and a fibular crest is not evident. I've not seen Huene's 1934 
paper on _Liliensternus_.

Therefore, presence of fibular crest is apparently common to 
coelophysoids, neoceratosaurs and tetanurans.

CARCHARODONTOSAURIDS AS ABELISAURS

Coria's suggestion that carcharodontosaurids are abelisaurs is not 
just published in Currie and Padian (1997) - it also deserves mention 
in Sampson et al. (1998): the _Majungatholus_ paper. Coria's 
characters are all based on cranial ornaments and the fact that the 
postorbital invades the orbit as a rostral flange. This is seen 
convergently in tyrannosaurids, and in fact I think all of these 
characters are prone to homoplasy and are outweighed by the 
characters uniting Allosauroidea. 

The new _Geology Today_ has an article by Lingham-Soliare on 
predation in tyrannosaurs. Nice photo on the cover of some tarbosaur 
specimens.

"Never trust a tidy scientist"

DARREN NAISH
darren.naish@port.ac.uk