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RE: Paper on drepanosaurids


Christopher Taylor wrote:

Amongst the conclusions: Drepanosaurids are stem group diapsids, not
archosauromorphs, and not related to prolacertiformes. Archaeopteryx,
Ornitholestes and Sinosauropteryx were included in the analysis to test the
Feducci-oid theory that birds are derived from Avicephala - they're not.

In Senter's analysis _Longisquama_ falls right out of the Archosauriformes, a long long way from birds. Still, I don't think this sounds the death-knell for the loopy idea that birds evolved from an animal closely related to _Longisquama_, since aherents of this idea eschew cladistic methodology.

I think it's great that the bizarre gliding reptile _Coelurosauravus_ is coming out near the drepanosaurids. _Coelurosauravus_ has a lateral gliding membrane supported by long bony rods of dermal origin in the thoracolumbar region.

Forgive my ignorance, but what sort of a beastie is _Mesosuchus_? 

_Mesosuchus_ is a basal rhynchosaur, I believe.






Tree:

0--Palaeothyris
 `--+--Petrolacosaurus
    `--+--Avicephala
       |        |--+--Longisquama
       |        |  `--Coelurosauravus
       |        `--Drepanosauridae
       `--+--Youngina
          `--+--Gephyrosaurus (for Lepidosauria)
             `--+--Mesosuchus
                `--+--Prolacertiformes (incl. Tanystropheidae)
                   `--Archosauriformes

    Forgive my ignorance, but what sort of a beastie is _Mesosuchus_?


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