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Neovenator (was Re: Allosauria redefined)



I've just recently had the chance to take a good look at the 
*Neovenator* from Surrey, England, and there seems to be a real 
interesting allocation of this theropod to the African 
carcharodontosaurids. Perusing the skeleton, and matching it with 
similar skeletons, I've found that the closest match was with 
*Afrovenator*. There a list of synapomorphies, which include:

*  broad scapula with shortend rectangular coracoid (Afro's is flanged 
   at the end, while Neo's is not)
*  ischium is long a slender with small obturator process, and has a\
   distal boot (this feature is also shared with *Eustreptospondylus*
   from earlier beds (Oxford Clay) on the mainland)
*  the tibia has a very large cnemial process (another feature shared
   by a derived theropod, *Acrocanthosaurus*, to a greater degree and
   morphological similarity to that dinosaur)
*  the neural spines of the posterior caudals are hypershortened at
   the half point in the tail
*  the maxilla is elongate
*  the naris is expanded posteroanteriorly

Characters that *Neovenator* and *Afrovenator* do not share:
*Afrovenator abakensis* Sereno et al, 1996 (Niger [{In Abaka}]) late 
Early Cretaceous or early Late Cretaceous

-------------
*  large maxillary teeth (based on one tooth from only tooth-bearing
   bone of known skull)
*  small antorbital more triangular (ie, primitive, based on other
   eustreptospondylids and basal allosaurians) than circular
*  neural spines of cervicals short

*Neovenator salerii* Hutt, Martill, Barker, 1997 (England [Surrey {Isle 
of Wight}]) early Late Cretaceous, Aptian, Wealden Group

------------
*  small maxillary teeth (based on maxilla; premaxilla lacks teeth and 
   dentary indetirminate for *Afrovenatro* lacks this bone)
*  large antorbital more circular than triangular
*  neural spines of cervicals tall (not much more than *Allosaurus*)


These synapomorphies are close enough and their differing characters not 
separating enough, to define a taxon that includes them as derivatives 
of the Eustreptospondylidae, and Afrovenatorinae wouldn't be a bad name 
for this, based upon the above characters.

I do not base this on any similarities of the name, just before anybody 
grills me on that.

Jaime A. Headden

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