Re: Scipionyx position

[HPB1956@aol.com]

Tracy L. Ford wrote on 12/21/2001:

>>
It is considered a basal coelurosaur because of the presence of the following primitive features: prefrontal well-developed; lacrimal robust; acromion present, rounded coracoid ;ischial distal expansion (ischial foot?); 4th trocanter weakly developed ;  unexpanded , thin v-shaped chevrons.
 
These are given in the book.
<<

IIRC Scipionyx is regarded a juvenile. If true it may lack some derived characters due to being juvenile. This in turn would automatically lead to a basal position inside Coelurosauria in a cladistic analysis. BTW in the last cladogram which Thomas Holtz presented to the DML Scipionyx was found to be the most basal coelurosaur.

I think to solve this question we have to find a fossil which can be shown to be the adult form of Scipionyx.

Cheers


Heinz Peter Bredow