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Chinese sauropod info
As I promised, here are the Upchurch refs:
Upchurch, P. 1995. The evolutionary history of sauropod dinosaurs. Phil.
Trans. R. Soc. Lond. B, 349: 365-390.
Upchurch, P. 1998. The phylogenetic relationships of sauropod dinosaurs.
Zoological Journal of the Linnean Society, 124: 43-103.
Upchurch, P. 1999. The phylogenetic relationships of the Nemegtosauridae
(Saurischia, Saruopoda). Journal of Vertebrate Paleontology, 19(1): 106-125.
Upchurch propsed a Eusauropoda which comprises all sauropods above
Vulcanodontidae (Barapasaurus, Ohmdenosaurus, Vulcanodon, Zizhongosaurus)
and incorporates both the Euhelopodidae and Cetiosauridae as outgroups to
the Neosauropoda, which includes all other sauropods.
According to Upchurch, his Euhelopodidae contains the following genera:
Datousaurus, Euhelopus, Mamenchisaurus, Omeisaurus, Shunosaurus. Upchurch
considers the tail club in Shunosaurus to be an autoapomorphy rather than a
synapomorphy of the Euhelopodidae.
Here are the seven synapomorphies Upchurch has used to justify Euhelopodid
1. Caudal end of the prefrontal is triangular in dorsal view (convergently
acquired in Diplodocidae); 2. 13 cervical vertebrae (convergently acquired
in Brachiosaurus and Diplodocidae); 3. Laterally compressed cranial cervical
vertebrae; 4. Centroparapophyseal lamina on middle and caudal dorsal neural
arches (absent in some euhelopodids; convergently acquired in the
Neosauropoda); 5. cranial process on middle and distal chevrons
(convergently acquired in the dicraeosaurid-diplodocid clade); 6. Ventral
midline slit on middle and distal chevrons (convergently acquired in the
dicraeosaurid-diplodocid clade); 7. Prominent parasagittally oriented ridge
on the dorsal surface of the sternal plate.
I encourage anyone interested to look up these articles and read them for a
somewhat different and interesting view on sauropod evolution.
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