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RE: K-Pg extinction global firestorms



David Marjanovic wrote-

> *Vegavis*, itself less than 70 Ma old, doesn't count anymore: the latest
> phylogenetic analysis of Mesozoic birds (part of the redescription of
> *Chaoyangia*; Journal of Systematic Palaeontology, online-early; Jingmai
> O'Connor is one of the authors, probably the first) finds it outside of
> what should be called Gallanseres. (Possibly even outside Neornithes,
> because there aren't any other neornitheans in the matrix.)

Hold on a minute.  O'Connor and Zhou's analysis doesn't even include most of 
the characters the Vegavis description used to place it by Anas- lack of a 
pneumatic foramen on the proximomedial surface of ribs; apneumatic coracoid; 
ovoid m. scapulohumeralis cranialis scar; diminutive pectineal process on 
pelvis; numerous hypotarsal cristae.  

It does contain- hypotarsus with well developed cristae and sulci (but Vegavis 
and Anas are miscoded as lacking it); metatarsal II shorter than IV (but 
Vegavis is miscoded as lacking it).

It groups Anas with Gallus instead of Vegavis because of- medially hooked 
acrocoracoid (but Vegavis is miscoded as lacking it); supracoracoidal nerve 
foramen of coracoid displaced so that it no longer passes through the coracoid 
(true, but also absent in the non-included Presbyornis and Anatalavis); 
coracoid, sternolateral corner present and with a distinct omal projection 
(truem, but also absent in the non-included Anatalavis).

So, a combination of missing characters, miscodings, and missing intermediate 
taxa.  I'd say Vegavis is still secure in Anatiformes.

Mickey Mortimer