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Thecodontia defined and saurischian Marasuchus



Mark Van Tomme sent me a pdf of a new paper-

Kischlat, 2002. Tecodoncios: A aurora dos Arcosaurios no Triassico. in Holz
and De Rose (eds.). Paleontologia do Rio Grande do Sol. 273-316.

The paper's not in English, but does contain a lot of new phylogenetic
definitions.  I'm not really up on non-dinosaurian definitions, so perhaps
some of those are taken from older works.

Thecodontia (Protorosaurus + Thecodontosaurus)
Suppose there is such thing as a thecodont now, and it's a
heterodefinitional synonym of Archosauromorpha.  Were protorosaurs,
rhynchosaurs and trilophosaurs ever thought of as thecodonts?  I figured
they were eosuchians or something back in the day.

Protorosauria (Protorosaurus <- Crocodylus)

Archosauriformes (Proterosuchus + Crocodylus)

Proterosuchia (Proterosuchus <- Crocodylus)

Erythrosuchia (Erythrosuchus <- Crocodylus)

Proterochampsia (Proterochampsa <- Crocodylus, Vultur)
At least the man knows to use eponymous names in definitions.

Archosauria (Crocodylus + Megalosaurus)
I actually like this definition, since birds weren't originally archosaurs,
right?

Crocodylotarsi (Crocodylus <- Vultur)

Crurotarsi (Crocodylus + Belodon + Ornithosuchus)

Dromaeosuchia (Crocodylus + Ornithosuchus)

Ornithosuchia (Ornithosuchus <- Crocodylus, Vultur)

Belodontia (Belodon <- Aetosaurus, Crocodylus)
Uhh... isn't it bad enough we have Parsuchia and Phytosauria for this clade,
do we need a third name? Especially one based on indeterminate remains...

Aetosauria (Aetosaurus <- Belodon, Crocodylus)

Crocodylomorpha (Crocodylus <- Postosuchus)

Hallopoda (Hallopus <- Crocodylus)
Do we even know where in the mono/paraphyletic mess of sphenosuchians
Hallopus goes?  Well, Kischlat does include it in his preliminary cladistic
results from a crurotarsan analysis.  But nobody else has, to my knowledge.

Crocodyliformes (Crocodylus <- Protosuchus)

Avemetatarsalia (Vultur <- Crocodylus)

Ornithodira (Vultur + Pterosaurus)
Well, the absence of a Pterosaurus invalidates this name and the next two.

Pterosauromorpha (Pterosaurus <- Megalosaurus)

Dinosauromorpha (Megalosaurus <- Pterosaurus)

Dinosauriformes (Megalosaurus + Lagosuchus)
This clade was created to include Marasuchus, so the latter should really be
in the definition.  Especially since the precise placement of Lagosuchus is
uncertain.

Dinosauria (Megalosaurus + Hylaeosaurus)
Hylaeosaurus instead of Iguanodon why?

Ornithischia (Stegosaurus <- Allosaurus)

Neornithischia (Stegosaurus + Ceratops)
This is equivalent to Genasauria

Saurischia (Allosaurus <- Stegosaurus)

Pachypodosauria (Morosaurus <- Allosaurus)
And Morosaurus is used instead of Camarasaurus why?  Interesting idea for
the stem-sauropodomorph group though.

Sauropodomorpha (Plateosaurus + Morosaurus)

Theropoda (Allosaurus <- Morosaurus)

Neotheropoda (Ceratosaurus + Allosaurus)
I have to agree with Wilson et al. (2003) that the more inclusive
(Coelophysis+birds) definition has priority.

A new rauisuchian is named- Karamuru vorax Kischlat and Barbarena.

There's some additional information on Teyuwasu.  The femur's 260 mm, the
tibia's 270 mm.  Additional remains include pelvic fragments and a dorsal
centrum.

Kischlat presents preliminary results of (his?) analysis, showing the
following topology-
|--Prolacerta
`--+--Proterosuchus
   `--+--Rhamphorhynchus
      `--+--Euparkeria
         `--+--Proterochampsia
            `--+--Crocodylotarsi
               `--+--Lagerpeton
                  `--+--+--Pisanosaurus
                     |  `--Hypsilophodon
                     `--+--Marasuchus
                        `--+--+--Staurikosaurus
                           |  `--Plateosaurus
                           `--+--Eoraptor
                              `--+--Herrerasaurus
                                 `--+--Rioarribasaurus
                                    `--Allosaurus
Yes, saurischian Marasuchus and sauropodomorph Staurikosaurus, not to
mention very basal pterosaurs.

Finally, there's details about an Abaporu loricatus, which may be a new name
for Prestosuchus loricatus.  It's said to resemble Marasuchus and
saurischians in epipophyseal and neurapophyseal detailsa, but also
poposaurids.  Could it be dinosaurian?

I can send a pdf to those who want one.  Maybe someone who can read
Brazilian wants a copy (hint, hint).

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