PARAPHYLETIC 'COELOPHYSOIDS'

[darren.naish@port.ac.uk]

On ceratosaur paraphyly, Tom wrote..

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Yes, several recent studies support a topology of 
Coelophysoidea + (Ceratosauria + Tetanurae); in fact, 
classical "coelophysoids" are paraphyletic in Rauhut's 
analyses. 
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What I find especially interesting about Rauhut's placement 
of _Dilophosaurus_ closer to Tetanurae than to 
Coelophysoidea is that this topology is dependent on the 
inclusion of _Shuvosaurus_. As he notes on p. 167, when 
_Shuvosaurus_ is excluded, a coelophysoid 
_Dilophosaurus_ is as parsimonious as a non-coelophysoid 
one. It's significant then that Carrano et al. (2002) also 
found _Dilophosaurus_ closer to tetanurans than to 
coelophysoids, but didn't include _Shuvosaurus_.

Note though the possibility that some of the characters that 
put _Dilophosaurus_ closer to tetanurans than to 
coelophysoids might be size related. 

Re: Neotheropoda - of course the original usage of this 
name by Bakker excluded coelophysids.

BTW, can I encourage people to use 'tetanuran' (or 
tetanuraen?) rather than 'tetanurine'? Tsk tsk John...

-- 
Darren Naish
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL

email: darren.naish@port.ac.uk
tel: 023 92846045