RE: Sauropods Size

["Thom Holmes" <tholmes@dolphinsoft.com>]

Greg Paul did a reconstruction of Amphicoelias fragillimus based on its
known vertebra (which was close to eight feet tall, I believe) in which he
estimated it to be about 200 feet long. Several  people, including Ken
Carpenter and Jack McIntosh in particular, have been puzzling over the
location of this lost fossil and have tried to trace its path but with no
luck yet as far as I know. After having been in touch with the Cope family
for my research on E.D., I have been exploring a couple of other
possibilities for its location, but again with little results. It has
probably been lost forever. Let's hope there is another specimen out there
waiting to be discovered.

--Thom Holmes
dinosaur writer at large

-----Original Message-----
From: Dinogeorge@aol.com [mailto:Dinogeorge@aol.com]
Sent: Wednesday, April 14, 1999 3:39 PM
To: tholmes@dolphinsoft.com; laibly@blue.weeg.uiowa.edu;
dinosaur@usc.edu
Subject: Re: Sauropods Size


In a message dated 4/14/99 11:31:29 AM EST, tholmes@dolphinsoft.com writes:

<< Jack McIntosh, David Gillette, Rodolfo Coria, and Brian Curtice are all
 expert on the biggest of the big. Gillette named Seismosaurus, currently
 considered by most to be the longest sauropod at about 150 ft. Curtice
 recently compared Supersaurus and Ultrasaurus and helped determined their
 status in relation to Brachiosaurus. I just visited Rodolfo Coria in Plaza
 Huincul, Argentina and saw the bones of Argentinosaurus in his museum--this
 is considered the largest (weight/height) of the sauropods. And Jack, of
 course, is a leading expert on all sauropods. >>

Largest sauropod overall: Amphicoelias fragillimus
This is the largest dinosaur ever described in the scientific literature.
Trouble is, the only known specimen is a huge partial vertebra (a neural
arch--the upper part of a vertebra: largest such fossil ever described) that
is estimated, when complete, to have been more than two meters tall. This
fossil was extremely fragile (very thin bony laminae) when Cope described it
in 1878 (hence the species name: and we need the species name because Cope
also described smaller species in the genus Amphicoelias), and it apparently
didn't survive intact after he measured and described it. It was not in the
Cope collection acquired by the American Museum and it is believed
destroyed;
all we have of it is Cope's description. But (as I recall) the description
and illustration are good enough to identify the neural arch as belonging to
a gigantic diplodocid. If this dinosaur had roughly the same proportions as
its smaller relative, Diplodocus, then it would have been >at least< 150
feet
long and would have weighed about 100 tons--something like a blue whale on
four legs. These figures would make it both the longest and the heaviest
dinosaur on record. I understand that paleontologists have tried to relocate
the site where this vertebra was found (somewhere in Colorado), in case
there
is more of this dinosaur still in the ground, but so far no luck. I'd
appreciate anything that might be added to this thumbnail account.