Yangdangornis

["Timothy Williams" <twilliams_alpha@hotmail.com>]

I just received the paper describing _Yangdangornis longicaudus_, the new 
long-tailed bird from China.  On p.439 the authors (Cai and Zhao) state 
"..the new bird has been examined by many scholars at home and abroad.  Some 
of them consider that it is a small theropod dinosaur."

No kidding.  The bird is not really all that bird-like.  Most of the lower 
forelimbs (apart from two digits of one hand) are missing, so it's hard to 
tell how long they were.  The authors say the ulna is shorter than the 
femur, although both ulnae are missing theit distal portions.   Alas, only 
the ventral side of the skull is preserved.  The tail is indeed very long - 
305mm, around half the total body length - and no sign at all of any fusion.

Cai and Zhao suggest that _Yangdangornis_ had "become a primitive bird 
adapted to ground dwelling", retaining its long tail but its forelimbs were 
subject to "degeneration".  Not a lot is discussed regarding its 
phylogenetic position in the Aves, although the Sauriurae vs Ornithurae 
dichotomy is wheeled out (the authors put _Yangdangornis_ in the former).

The specimen was found associated with _Zhejiangopterus_.  The stratum is of 
early Late Cretaceous age (81.5 Ma BP).

That's all for now.  I'll send a follow-up post with more info on anatomy 
and provenance.


Tim
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