Re: Notarium question

[Graydon <oak@uniserve.com>]

On Mon, Aug 18, 2003 at 01:23:06PM +0200, David Marjanovic scripsit:
> > The pterosaur notarium articulation is a new structure, that is, one
> > not present on Ichthyostega. I'm trying to think of other such
> > examples in tetrapods, but I'm coming up almost blank.
> 
> There aren't many, AFAIK. The mammalian 2nd jaw joint ( = only jaw
> joint in the crown group, between squamosal and dentary) is one. And
> the teeth on the palatal rami of the premaxillae of *Haptodus*
> http://tolweb.org/tree/eukaryotes/animals/chordata/synapsid_lichen/synapsida_synapomorphies.html
> - - pmx teeth are normal, teeth on the palate are normal, but palatal
> teeth on the pmx are AFAIK unique. (Unfortunately. A few denticles on
> mine would be very practical for munching hard stuff like cornflakes.
> :-} )
> 
> Or do you mean new bones, too? Could the sternum be one, er, two?

Ceratopsian rostral bone is not found in Ichthyostega, too.

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