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Re: Senter, P. 2004



David Peters wrote-

> 1. The taxa I, and others, found to be closest to the Drepanosauridae
(Protorosaurus, Borepricea, Jesairosaurus) were not included. Most of the
problems and major hurdles would go away with the inclusion of these three
taxa. Only 20 taxa and 73 characters were included in Senter's analysis.
Twice as many characters would help.
>
> As a result Longisquama + Coelurosauravus were found to be the outgroup to
the Drepanosauridae.

Senter's paper is a modified portion of his thesis, which includes a much
larger phylogenetic analysis (85 taxa, 215 characters).  This analysis
includes Protorosaurus.  I would suppose he thought prolacertiformes were
well covered with Prolacerta, Protorosaurus, Macrocnemus, Langobardisaurus,
Cosesaurus, Sharovipteryx, Longisquama and Megalancosaurus.

> 2. The taxa I (Peters 2000) found to be closest to Longisquama
(Sharovipteryx and the Pterosauria) were not included in Senter's analysis
(ignored, according to him out of "laziness" [direct quote]).

His thesis' analysis also includes Sharovipteryx and two pterosaurs
(Austriadactylus and Eudimorphodon).

> If you don't invite the right taxa to 'the dance,' you end up with less
than optimal results. Unfortunately, I don't think any of Senter's proposed
clades nomenclature will prove valid or useful, and the relationships of the
drepanos to others have not been elucidated.

The irony of your first statement is that Senter actually describes this
phenomenon in some detail in his thesis, which is why he included so many
taxa in his diapsid analysis.  The phylogeny is roughly the same as the
drepanosaur paper, though much expanded.
|--Paleothyris
`--+--Petrolacosaurus
   `--+--+--Coelurosauravus
      |  |--Longisquama
      |  `--Megalancosaurus
      `--+--Icarosaurus
         `--+--Younginia
            `--+--+--Askeptosaurus
               |  `--Palaeopleurosaurus
               `--+--+--Monjurosuchus
                  |  `--Hyphalosaurus
                  `--+--+--Protorosaurus
                     |  `--+--Prolacerta
                     |     `--+--Macrocnemus
                     |        `--+--Sharovipteryx
                     |           |--Langobardisaurus
                     |           `--Cosesaurus
                     `--+--Proterosuchus
                        `--+--Euparkeria
                           `--+--+--Parasuchus
                              |  `--+--Ornithosuchus
                              |     `--+--+--Saurosuchus
                              |        |  `--Postosuchus
                              |        `--+--Gracilisuchus
                              |           `--+--Sphenosuchus
                              |              `--+--Saltoposuchus
                              |                 `--+--Dibothrosuchus
                              |                    `--+--Alligator
                              |                       `--+--Malawisaurus
                              |                          `--Protosuchus
                              `--+--+--Scleromochlus
                                 |  `--+--Eudimorphodon
                                 |     `--Austriadactylus
                                 `--+--Marasuchus
                                    `--44 dinosaurs + 7 birds
Peters' three important taxa are all included, but Pterosauria still falls
out in Avemetatarsalia.

Mickey Mortimer
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html