Re: Hadrosaur nomenclature

[Paleo_Mont <paleo_mont@excite.com>]

Ok...guess I need to do something here, again. 

>Maiasaura = Brachylophosaurus<
>I admit I don't know much about hadrosaurs, so maybe this is old, but I
haven't heard it before. What's the reasoning behind this

>  Because the look similar. I'm not being smart. The Mor adult Maiasaura
skull is crushed dorsal-ventrally. ROM has a new uncrushed skull that really
really looks like Brachylophosaurus without that crest in the back.  

Arg... Hello not that similiar. That specimen is not that new. 93/94/95 or
so when it was acutally found. Is also, the same speciman that has the skin
impressions that show a "waddle" (loose skin under the neck). 

>Fun thought: Brachylophosaurus is a male Maiasaura (or vice versa). Boy, we

really don't know >anything< about dinosaurs, do we? 

<cough>bs<cough> Well maybe you...<grins>.  

1. _Brachylophosaurus_ is a JUDITHIAN Dinosaur.

2. _Maiasaura_ is a TWO MEDICINE Dinosaur. 

3. Same time period yes. Different Enviroments yes. 

4. No Two Medicine Dinosaur has been found outside of the Two Medicine
formation.(fragmented and isolated teeth dont count, cause you cant use them
to determine actual specimens!.. ex:Troodon)

5. There are two types of Maiasaurus skulls a broad and a narrow snout/beak.

6. Both animals, Frontal, Postorbbital, Jugal, Premax, Nasal, Maxilla, are
very different. Can see that when you look at both skulls together.

7. Brachylophosaurus has small flat crest that begins before the orbit and
continues back past the post-orbit.

8. Maiasaurus has a  well it doesnt really have much of a crest. The bone
that makes up the crest is a bit procurved. It lays right before the orbit,
curves forward abit.

9. The nasal opening in Brachylophosaurus is longer.

10. Brachylophosaurus has a more rounded snout/beak then Maiasaurus.

11. What I babbled abbout last night... they both have and ungal ridge.
Which was only known in Maiasaurus until a few years ago, when ungauls were
found with an articulated Brachylophosaurus.( That particular ungaul was
found in the Claggot of central MT.) And has been changed to being
Brachylophosaurus.

12. Any questions?  I hope I have cleared it up. Also take a look at the
specimens yourself. The nice Maia, skull that Tracy refered to can be found
on the ROM website, http://www.rom.on.ca/ after looking for it in the
Maiasaur project. Or if you have the Dinosauria can see them both in there,
cept you see the crushed Maia skull. The info about the two skull types of
Maiasaura, came from Dave Trexler's masters thesis from U of Calgary.
Probally most of you dont have access to that, but He is going to get it
ready to publish for next year.

13. Thats all.


K.Wicks

Paleo Mont - www.geocities.com/paleo_mont
Paleo Mont Park - www.geocities.com/paleo_montpark





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