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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.