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RE: Newcomer (Male) with a few things to share (2nd attempt)
Jamie Stearns wrote-
My name is Jamie Stearns. I am 18 and going into college, hopefully to
become a paleontologist. I've been interested in dinosaurs since I was 5,
and have recently completed a massive cladogram containing every taxon I
could find sufficient information on, using several different websites as
well as the archives of this list.
Hi Jamie! You remind me of myself at your age-
http://dml.cmnh.org/2000Mar/msg00304.html
Am I to assume your cladogram should be indented? So it would actually be
like this?
|--Ornithischia
`--+--Sauropodomorpha
...`--+--Guaibasaurus
......`--+--Eoraptor
.........`--+--+--Herrerasaurus
............|..`--Staurikosaurus
............`--+--Segisaurus
etc.
Non-Coelurosaurian Theropods:
|--Ornithischia
|--Sauropodomorpha
|--Guaibasaurus
|--Eoraptor
|----Herrerasaurus
| `--Staurikosaurus
|--Segisaurus
|--Procompsognathus
|--Coelophysis
|--Syntarsus
|--Gojirasaurus
|--Liliensternus
|--Dilophosaurus
|-----Elaphrosaurus
| |--Spinostropheus
| |--Ceratosaurus
| |--Rugops
| |----Masiakasaurus
| | `--Noasaurus
| |----Abelisaurus
| | `--Indosuchus
| |--Ekrixinatosaurus
| |----Aucasaurus
| | `--Carnotaurus
| |--Majungasaurus
| `--Rajasaurus
|-------Megalosaurus
| | `--Poekilopleuron
| |--Torvosaurus
| |----Baryonyx
| | `--Suchomimus
| |--Irritator
| `--Spinosaurus
|--Eustreptospondylus
|--Gasosaurus
|-----Cryolophosaurus
| |--Piatnitzkysaurus
| |--Afrovenator
| |--Monolophosaurus
| |--Fukuiraptor
| |-----Siamotyrannus
| | |--Metriacanthosaurus
| | |--Sinraptor
| | `--Yangchuanosaurus
| |--Allosaurus
| |--Neovenator
| |--Acrocanthosaurus
| |--Tyrannotitan
| |--Carcharodontosaurus
| |--Giganotosaurus
| `--Mapusaurus
`--Coelurosauria
My preferred phylogeny is here-
http://students.washington.edu/eoraptor/Phylogeny%20of%20Taxa.html
I could not find much information on *Dubreuillosaurus* and the identity of
*Shuvosaurus* seems somewhat problematic, so I'm not sure exactly where to
put either one.
Dubreuillosaurus is very similar to Afrovenator (Holtz et al., 2004).
Shuvosaurus is a crurotarsan, as shown by the discovery of Effigia (Nesbitt
and Norell, 2005).
I agree with Rauhut on the placement of *Dilophosaurus* as well as the
inclusion of *Afrovenator* within Carnosauria (however, I find it to be
somewhat more basal than Rauhut). Piatnitzkysaurus may belong here too, as
it also seems to have the characteristic lacrimal ornamentation and the
narrow frontal between the eyes shared by other carnosaurs, though I'm not
sure its lacrimal is known.
Nope, no lacrimal is known for Piatnitzkysaurus.
I'm not sure why coelophysids are considered monophyletic. *Gojirasaurus*
and *Liliensternus*, at least the reconstructions I've seen of them, appear
to be closer to *Dilophosaurus* at least in size and robust build than
either is to *Coelophysis*, though I may be missing something here.
Tykoski (2005) found Liliensternus and Zupaysaurus to share the following
characters with other coelophysids- alveolar ridge on maxilla; deep ventral
fossa on ectopterygoid; low post-axial cervical neural spines; ischiopubic
ratio <66%; proximal end of metatarsal III with ventral boss; anterior ramus
of maxilla <10% maxillary length; more than 19 maxillary teeth; anterior
margin of antorbital fossa squared; anterior lacrimal process longer than
ventral process; cervical ribs fused to vertebrae in adults.
Finally, *Elaphrosaurus* and it's relative *Spinostropheus* are also pretty
hard to place, given that they're alternately placed as coelophysids (well,
*Elaphrosaurus* at least), more derived ceratosaurs, basal abelisaurs, or
even close to the beginning of Noasauridae. I have them as basal to
(*Ceratosaurus*+Abelisauria) at the moment.
What characters do Ceratosaurus and abelisaurs share that Spinostropheus
doesn't?
I look forward to seeing your coelurosaur cladogram.
Mickey Mortimer