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At 02:46 PM 7/27/98 -0400, Dinogeorge wrote:
>The new Lower Jurassic Lufeng segnosaur jaw, only a few inches long, described
>in the current _Nature_ (July 16) as a therizinosauroid jaw, (1) looks very
        That is good to know. I can't wait to see it (actually, I can and
will wait until the end of the summer when my copy bills are paid off).

>(2) looks somewhat prosauropodan or even ornithischian; and (3)
>does >not< look at all coelurian: ornithomimid, oviraptorid, troodontid,
>dromaeosaurid, tyrannosaurid, maniraptoran, 
        Granted that (temporally) later therizinosaur jaws don't look all
that much like any of these boys either. Of course, this could have
something to do with dietary preference...

>or even theropodan. Unless you think that basal coelurians should have lateral
>shelves on their dentaries
        I'm not sure that therizinosaurs are *basal* coelurosaurs
("coelurians"?) at all. For that matter, it will take some evidence to
convince me that the new specimen is a *basal* therizinosaur, as opposed to
merely representing the FAD of therizinosaurs.

>lateral ridges on their coarsely serrated, leaf-shaped teeth, that is.
        If the specimen is a therizinosaur, then it can be minimally
expected to exhibit those features which are considered characteristic of
therizinosaurs, regardless of taxonomic assignment/phylogenetic position.
Unless I've been leaking data out of my thick skull (quite possible, I am a
student after all...), the shelf and leaf-shaped teeth are also present in
other therizinosaurs. As for the ridges, I am not currently sure. Please do
expand upon this.

        A good question remains: are therizinosaur (ok George, segnosaur)
bones hollow? Do they exhibit any other osteological characteristics
commonly associated with theropods (e.g. very compact lamellar bone)?

    Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
                    "...To fight legends." - Kosh Naranek