Re: Sauropods Size

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

At 04:31 PM 4/14/99 -0500, Tim Williams wrote:

>As I understand it, most of the knowledge of this genus comes from 
>_A. altus_, not _A. fragillimus_, and I don't know to which species 
>Wilson and Smith refer the new material.  I have seen _A. altus_ 
>listed as a junior synonym of _A. fragillimus_.  Does anybody know 
>why _A. altus_ is referred to the genus _Amphicoelias_? 

Because it is the type species...  _Amphicoelias altus_ Cope 1877, _A.
fragillimus_ Cope 1878.

Osborn & Mook (in their 1921 review of sauropods) and McIntosh (see below)
doubt that there was sufficient cause to erect a new species for the giant
specimen, and consider it provisionally referrable to _A. altus_.

McIntosh's most recent published review of _Amphicoelias_ is in:
McIntosh, J.M.  1998.  New information about the Cope Collection of
sauropods from Garden Park, Colorado.  Modern Geology 23:481-506.

He discusses (among many other things) the loss of the _A. fragillimus_ type
(for which the number AMNH 5777 was reserved, although no record shows it
ever arrived at New York).  He also says:
"Although loss of the fossil [is] a major tragedy, there is no reason not to
consider it a very large individual of _Amphicoelias altus_." (p. 502)

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