Amargasaurus (was Re: Quaesitosaurus and Nemegtosaurus)

["Thomas R. Holtz, Jr." <th81@umail.umd.edu>]

At 12:15 PM 12/12/96 -0500, Nick Longrich wrote:

>> I wonder then if _Antarctosaurus_, which has also been 
>> reconstructed with a very diplodocoid-like skull, might be a 
>> titanosauroid after all.
>
>       Amargasaurus, however, is generally reconstructed as
>diplodocid, so that would argue that they were in S. America.

The possibility that Antarctosaurus (a late Late Cretaceous form) was a
titanosauroid does not change the observations that Amargasaurus (an early
Early Cretaceous form) was a dicraeosaurid diplodocoid.  All recent studies
have placed Amargasaurus quite close to Dicraeosaurus.

>Then again, if Opisthocoelicaudia has cleft neural spines and
>peglike teeth...

Peglike teeth are found in titanosauroids and in diplodocoids.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661

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