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On Thursday, September 19, 2002, at 12:52 PM, Dino Guy Ralph wrote:

Fam Jansma wrote:

Has anyone noticed the similarities in the dentition between this new genus
and that of Protoarchaeopteryx with the LARGE premaxillary teeth?

The procumbent premaxillary teeth of _Protarcheopteryx_ are described as bearing
needle-like crowns and bulbous roots and showing minute serrations. This
description does not match the large rodent-like _Incisivosaurus_ two front
teeth and the remaining three premaxillary pairs of much smaller, more slender,
unserrated, subconical teeth. Furthermore, the mode of preservation and the
strata do not compare either, as _Incisivosaurus_ predates _Protarchaeopteryx_.
Unfortunately, there is little overlap for comparison between the two genera,
but at present it appears safe to assume that these are distinct theropods.

Given that Protarchaeopteryx has:

-procumbent premaxillary teeth (Incisivosaurus, Caudipteryx)
-enlarged premaxillary teeth (or reduced posterior teeth depending on how you look at it) (Incisivosaurus)
-a skull which is relatively short for its height (Caudipteryx, Oviraptoridae, Incisivosaurus)
- a relatively small skull relative to the size of the animal (Caudipteryx, Oviraptoridae, ?Therizinosauroidea, convergent in ostrich dinos)
-short distal caudal segments (Caudipteryx, Oviraptoridae, probably Caenagnathidae, Therizinosauroidea)
-digits II and IV of pes subequal (a reversal uniting it with Caudipteryx, Avimimus, Oviraptoridae, Caenagnathidae)

It looks quite likely that it is a basal member of the oviraptors, which is where I've usually got it in the past. It seems likely that it forms a grade/clade with Bunnysaurus.