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RE: II CLPV talk summaries: Day 2

Scott Hartman wrote:

Diego Pol presented data from new specimens of Mussaurus. [snip] Good thing too, as his phylogenetic analysis found that Mussaurus is quite a bit closer to true sauropods than Plateosaurus is.

It'll be interesting to see how this ties in with Yates (2004), who alluded to the non-prosauropod nature of _Mussaurus_ based on a number of characters, including procumbent teeth in the upper and lower jaws.

Yates, A.M. (2004). _Anchisaurus polyzelus_ (Hitchcock): The smallest known sauropod dinosaur and the evolution of gigantism among sauropodomorph dinosaurs. Postilla 230: 58 pp.

Sterling Nesbitt gave one of my favorite talks of the conference. He showed that Shuvosaurus is not an ornithomimid (no real surprise there), but is rather a derived suchian.

This directly contradicts previous work that puts _Shuvosaurus_ in the Theropoda, based on a long list of theropod characters in the skull. If _Shuvosaurus_ is a crurotarsan, then homoplasy is rampant indeed.

Randall Irmis was up next, and picked up where Sterling left off; they feel that a lot of North American Triassic dinosaurs aren?t and made a pretty convincing argument for it. A (non-
comprehensive) list includes Eucoelophysis, which they feel pretty strongly is a silesaurid. Which makes the name EU-coelophysis ironic, to say the least.

Yes - especially considering that Sullivan and Lucas (1999) believe that the original type specimen of _Coelophysis bauri_ (AMNH 2722) is probably referrable to _Eucoelophyis baldwini_. I wonder if it is possible that the hypodigm for _Eucoelophysis_ might be chimeric, and include both theropod and non-dinosaurian material. If not, and if the original _C. bauri_ holotype is in fact non-dinosaurian, *and* the holotype of _E. bladwini_ belongs to the same non-dinosaurian taxon, then the name _Eucoelophysis_ may indeed be appropriate. However, AMNH 2722 does look rather theropodan.

Gojirosaurus they feel is a chimera (Ken, want to comment?), made up of theropod material and Shuvosaurus (or shuvosaur-like suchian) material.

The idea that _Gojirasaurus_ and _Shuvosaurus_ are the same animal has been floating around for a while now. This means that the teeth that were found with the type _Gojirasaurus_ material belong elsewhere, since _Shuvosaurus_ is toothless.

Speaking of chimeras... like Mickey, I'm curious what happened to _Alwalkeria_.

Thanks for the postings, Scott. They were extremely helpful and interesting.