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Re: Misc. Questions



Dino Rampage wrote-

> 1) How is Marshosaurus related to other theropods? Is it a coelurosaur,
> carnosaur or spinosauroid?

Latest word is that it's a megalosauroid (=spinosauroid), based on
undescribed material (Chure and Britt, 1997).  I found some coelurosaur-like
characters several months ago though-
http://www.cmnh.org/dinoarch/2002Aug/msg00078.html
And of the supposed primitive characters placing it near megalosauroids-
1. a long braincase is found in most coelurosaurs, such as ornithomimids and
dromaeosaurids.
2. a rectangular laterotempral fenestra is seen in basal coelurosaurs like
Proceratosaurus, Ornitholestes and Scipionyx.
3. camerate vertebral pneumaticity is seen in dromaeosaurids, but most basal
coelurosaurs are unknown for this character.
4. a bowed pubic shaft is found in Coelurus, Ornitholestes, SMNK 2359 PAL
and to a lesser degree in some other basal forms.
5. the small pubic boot is seen in Scipionyx and Nqwebasaurus.
6. long low ilia are present in Ornitholestes, Compsognathus,
Sinosauropteryx and other such taxa.
7. inclined axial intercentra are only found in Sinraptor and
Monolophosaurus to my knowledge.
8. I know of no coelurosaur with cervical epipophyses approaching the height
of the neural spines.
9. opisthocoelus cervical centra are found in Eotyrannus, Calamosaurus and
Compsognathus.
10. a moderately expanded scapular blade is present in Sinosauropteryx,
Compsognathus and Nqwebasaurus.
11. open obturator notches are known in SMNK 2349 PAL and Coelurus.
12. short massive humeri are found in Sinosauropteryx.
Remember too that this undescribed material is only referred to Marshosaurus
based on similarities in dorsal neural spines to those referred to
Marshosaurus (found in the type locality).  They contain no pelvic material,
though the posterior dentary and maxilla might be preserved.

> 2) What dinosaurs inhabited the eastern half of North America during the
> Late Cretaceous?

Ignoring indeterminate material that fits into a category known from
diagnosable or named material (eg. Theropoda indet., Ornithomimidae indet.)-

Dryptosaurus aquilunguis
two undescribed basal tyrannosauroids
Coelosaurus antiquus
"Dromaeosauria" indet.
Ichthyornis dispar
Laornis edvardsianus
Palaeotringa littoralis
Palaeotringa? vagans
"Palaeotringa" vetus
undescribed neornithine
undescribed possible anseriform
Anatalavis rex
Graculavus velox
Telmatornis priscus
Tytthostonyx glauconiticus
unnamed procellariiform
Nodosauridae indet.
Ankylosauridae indet.
Lophorhothon atopus
Hadrosaurus foulkii
Hadrosaurus? cavatus
Hadrosaurus? minor
Hypsibema crassicauda

Mickey Mortimer