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re: Sinopterus cladistically



Jaime Headen wrote:

>>From what I have available, a possible *Tupuxuara* skeleton has long
legs and wings that look like this. <<

I agree with you to this extent: All pterosaurs have "long" legs if one
consideres diameter versus length.

But IMHO "Long legs" should be considered relatively, perhaps to ilium
length or to pes length. If we go that way, then Sinopterus has shorter
legs than dsungaripterids (relative to both ilium and pes) and longer
legs than tapejarids, nyctosaurs and pteranodons (which is a nice place
to be if you want to be a transitional taxon).

On the other hand, in Pterodaustro, which you referenced, the ilium and
pes are both relatively large, perhaps the largest, relatively, of all
pterosaurs, so on that scale, Pterodaustro would have, relatively
speaking, the shortest legs among pterosaurs.

If you consider the whole body, then Quetzalcoatlus would probably win
the short legs contest, which is really strange to think about when
you're considering how "long" the Q. femur and tibia are all by
themselves.

It's weird.

David Peters


>>Jaime Headen wrote:

  From what I have available, a possible *Tupuxuara* skeleton has long
legs and wings that look like this. My personal observation in the
pteranodont lineage, which includes a basal toothy dsungaripterid stock,

developed the long skull first, and shortening progresses to *Tapejara
wellnhoferi*. Consequently, I restore *Tapejara* with long legs and a
relatively short trunk, possibly with an overbite, though the underbite
in
*Dsungaripterus* and possibly *Thalassodromeus* may reflect feeding
style
and thus length of jaw to skull will have little phylogenetic
significance. The animal appears to resemble in the skull of *Tapejara
imperator* very much, and they may be sister taxa, or closer, with *T.
wellnhoferi* at the end. Might be good to separate *T. imperator* as a
new
"taxon" from typic *T. wellnhoferi* so that taxonomic confusion isn't
conflated. I think the orbital area is strongly distorted, as many
temporal elements appear to be broken or loose in the photo. Long legs
are
seen convergently in *Pterodaustro* and this may also reflect feeding
styles. Note that long limbs in many bird clades that are waders versus
swimmers or flyers, even closely allied, vary when the ecology is
considered. Food for thought. If anyone has access to the Chinese I
would
like to know, I prefer having both references, actually, for as Jerry
has
said, the original Chinese of many of the Kexue Tongbao/Chinese Science
Bulletin articles are the proper citation. I have both english and
Chinese
*Jinzhousaurus* (iguanodontoid from Jiufotang levels) articles, for
instance.
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