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Re: Aussie therizinosaurids?





It said that a characteristic of
Therizinosaurs is a large, bony crest on the humerus, the deltopectoral
crest.

Conspicuous by its absence is the lack of a sigmoidal shaft - courtesy of the distal "twist", which is quite obvious in the humerus of _Erlikosaurus_. Also in therizinosauroids, the humerus has a pointed internal tuberosity on its proximal end. This cannot be discerned in the Aussie bone.


So possibly, this is an
Australian
Therinosaur and based on relative proportions between the humerus of
Erlikosaurus and this beast, it was 1,5 times as big as that beast.

Based on the illustration, the humerus could come from a range of theropod taxa.


Not something you want to come across in a dark alley!

I think the biggest danger of encountering a therizinosaur in a dark alley would be if it trod on you by mistake. These large-bodied mega-clawed theropods seem to have been ponderous leaf-eaters.


And with Kakuru being a Avimimid,

I think this goes back to Greg Paul's _Predatory Dinosaurs of the World_, and is based on the similar proportions of the respective tibiae. Like _Avimums_, the shin bones of _Kakuru_ were very slender. I think we'll need more _Kakuru_ bones before we can be certain what this theropod was.


Australia becomes even more
interesting with this discovery, I hope, with [Ozraptor] being a
possible ancestor to the the raptors,

According to at least one palaeontologist, _Ozraptor_ is indeterminate and the evidence for its inclusion in the Maniraptora is weak.


the giant Alvarzsaurid Rapator,

This has not been published (AFAIK), but seems to be a safe bet.

the Euhelopid Rhoetosaurus,

This has been mentioned (or at least alluded to) to in several scientific articles. _Rhoetosaurus_'s referral to the Euhelopodidae is based principally on caudal morphology, I believe - especially, the presence of forked (or "skid-like") chevrons. However, considering the doubt surrounding the monophyly of Euhelopodidae (sensu Upchurch), the referral of _Rhoetosaurus_ to this family (or to Shunosaurinae sensu McIntosh, which Upchurch combines with _Euhelopus_ in the Euhelopodidae) is very tentative. Those forked chevrons are also found in diplodocids, and apparently pop up in a number of sauropod taxa.


the Titanosaurian "Hughenden Brachiosaurid" (could the new
partial skeleton be of this critter?) and Austrosaurus,

_Austrosaurus_ might be a titanosauriform - though, again, this placement is precarious.


Alas, Australia's only alleged prosauropod (_Agrosaurus_) appears to have hailed from Britain, and to belong to _Thecodontosaurus_. Its Antipodean provenance was nothing more than a case of specimen mislabelling. This means that Australia is the only continent not to have documented any prosauropod material. They've even been found in Antarctica.




Tim

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