Re: Does Baryonyx lack serrations on its teeth or not?

["Matthew Troutman" <m_troutman@hotmail.com>]

>Since _Baryonyx_ is suspected by some to be related to _Spinosaurus_
>and _Irritator_ (right?), does it also lack serrations on its teeth,
>then? Or is this possible relation based on other characters?

    Baryonyx has very minute, finely seratted teeth along the anterior 
and posterior ends and bear " fluting" teeth, whereas Spinosaurus does 
not. I think Irritator has unserrated teeth, though I'm not sure. But 
anyway, it seems painfully obvious that Spinosaurus and Baryonyx are 
closely related. The extent to this relationship is rather 
controversial. Charig and Milner ( 1990 ), rejected a relationship at 
the family level, mainly because of the teeth morphology. They 
reiterated this in 1997 maily based on the teeth. They characterize it 
by the elongation of the jaws, a non-terminal "rosette" in both jaws, 
upturned symphysial end of dentary with constricted posterior region, 
reduction of premaxillary tooth count, and tooth morphology. Sereno 
et.al. 1996 gave a different character set and it is more extensive. To 
summarize it : anterior ramus of maxilla long as tall, reduced or absent 
quadrate foramen, and elongate manual digit I. To view the complete set 
see Sereno et.al 1996. 
    Stay tuned for the next Sereno Morroco paper, it will _probably_ 
deal with this subject. ( Don't ask, my mouth is shut.)

WMattTroutman

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