CRETACEOUS STEGOSAURS

[darren.naish@port.ac.uk]

On Cretaceous stegosaurs, Tim wrote...

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>From the Early Cretaceous of England comes 
_Craterosaurus_ (?=_Regnosaurus_).  
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If these two are synonyms then you have it the wrong way 
round (though seeing as both should best be treated as 
nomina dubia this cannot of course be demonstrated). The 
holotype of _Craterosaurus pottonensis_ - the partial 
vertebra SMV B.28814 from the Lower K Potton Sands of 
Bedforshire - was first described and named in 1874 (as a 
partial lacertilian braincase). _Regnosaurus northamptoni_, 
based on the partial lower jaw BMNH 2422 from the 
Wealden of Sussex (extant location uncertain), was first 
described and named in 1848.

Lower Cretaceous stegosaur material really isn't as rare as 
some people seem to be implying. Besides _Craterosaurus_, 
_Regnosaurus_ and _Paranthodon_ there is 
_Wuerhosaurus_ (China), _Monkonosaurus_ (Tibet), the 
Broome Sandstone tracks (Australia), the Argentinian 
stegosaur, material from Cretaceous Morocco (mentioned 
by Russell 1996), and assorted bits and pieces from 
Cretaceous Portugal and the Wealden.

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?Stegosaurid material is also known from the Early 
Cretaceous of France (_Lexovisaurus_ sp.).
----------------------

_Lexovisaurus_ is a Middle Jurassic genus - are you sure 
about this? I don't have the literature to hand.

For reviews of Cretaceous stegosaurs see...

Galton, P. M. 1981. _Craterosaurus pottonensis_ Seeley, a 
stegosaurian dinosaur from the Lower Cretaceous of 
England, and a review of Cretaceous stegosaurs. _Neues 
Jahrbuch fur Geologie und Paläontologie, Abhandlungen_ 
161, 28-46.

Naish, D. & Martill, D. M. 2001. Armoured dinosaurs: 
thyreophorans. In Martill, D. M. & Naish, D. (eds) 
_Dinosaurs of the Isle of Wight_. The Palaeontological 
Association (London), pp. 147-184.

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

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