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Re: the importance of Qianosuchus
Plugging what is shown online in the excellent line drawing, Quianosuchus
nests as the sister taxon to Ticinosuchus, which begets aeotosaurs. Their
common ancestor was a sister to Vjushkovia.
I'd like to see that data matrix.
In the original paper, *Qianosuchus* comes out in Crurotarsi -- in a huge
polytomy. That's why the poor beast hasn't received more attention: nobody
knows what it is.
Incidentally, the... well... Standard Mandarin sound transcribed "q" is...
somewhere between ts and ch, and heavily aspirated. It can occur in front of
i and u (which is then pronounced the French way). Any vowels directly
behind these belong to the same syllable, BTW, so that _qian_ is a single
syllable that more or less rhymes with English "an".
Q also nests just below Turfanosuchus, the last known
common ancestor of crocs and dinos.
What? Are you really saying *T.* is a known common ancestor of crocs and
dinos?!? For that, you would need to show that
- *T.* lacks any autapomorphies (good luck when the soft anatomy is not
preserved... and not even the whole skeleton...)
- *T.* has the right stratigraphic age (IIRC it's much too young)
- the fossil record around the origin of Archosauria is so good that we
should not expect to find yet another side branch (I'd bet _real money_ that
it isn't -- we aren't talking about marine diatoms!).
These three reasons are why PAUP* _assumes a priori_ that no OTU is an
ancestor of any other and would find real ancestors as the sister-groups of
their descendants. (This can easily be simulated, and has been, even though
a simple thought experiment should be enough.)
And its nice to know that none of the metatarsals are
reduced in diameter. That little fact has big implications for
Irmis's so-called "dinosauromorphs."