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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