Re: Mamenchisaurus tail club

["ashmidt" <ashmidt@flash.net>]

This is really exciting news.  I can't wait to see Mamenchisaurus restored
with this new tail club and I wonder how its skull material compares with
the skull material known from other mamenchisaurus species (I recall at
least one other is known from skull material, saw it on a Discovery program
years ago).  Its certainly an interesting skull, with just an amateurs
perspective it looks like a cross between the Diplodocus and
Camarasaurus-like skulls (which were the two kinds they debated putting on
it all those years before skull material was known if I recall right).

Its also nice to see the amterial referred to an existing species instead of
creating a new one from it.  It seems to me this is done too often with
Chinese sauropods.

One question though.  How could something sensitive enough to be a sense
organ also function as a weapon (which would typically need to be tough and
resitent to damage)?  The two purposes seem to be mutually exclusive.
----- Original Message -----
From: <Dinogeorge@aol.com>
To: <dinosaur@usc.edu>
Cc: <Dinogeorge@aol.com>
Sent: Monday, August 19, 2002 4:29 PM
Subject: Mamenchisaurus tail club


> I've been going over some recent new references and have come across this
> one, which I don't recall being mentioned on the list before (maybe the
> messages were AOL-blocked?):
>
> Ye Yong, Ouyang Hui & Fu Qian-Ming, 2001. "New material of _Mamenchisaurus
> hochuanensis_ from Zigong, Sichuan," _Vertebrata PalAsiatica 39_(4):
266-271
> [October 2001; in Chinese with Engllish abstract].
>
> The authors describe a new partial skeleton (ZDM0126) referable to the
long
> sauropod _Mamenchisaurus hochuanensis_ that fills in some of the areas
> missing from the holotype skeleton. There is , for example, quite a lot of
> cranial material. In particular, they report a tail-club-like fusion of
the
> posterior caudals along with a concomitant elevation of their neural
arches:
> "The new materials show that the posterior caudals are fused with each
other
> and are expanded and cockscomb-shaped, which differ distinctly from the
> hammer-shaped tail of _Shunosaurus_ and _Omeisaurus_. We suggest that its
> posterior caudals have two main functions: it serves not only as a
defensive
> weapon, but also as an acute sense organ." (From the English abstract.)
>
> The paper also carries this reference in the bibliography:
>
> Zhang Y H, Li K & Zeng Q H, 1998. "A new species of sauropod dinosaur from
> the Upper Jurassic of Sichuan Basin, China," _J. Chengdu Univ of Technol
> 25_(1): 61-68 [in Chinese with English summary].
>
> This seems to be where the species _Mamenchisaurus jingyanensis_ is
> described. But I have a 1996 date for that species; it's rather well
figured
> in the article by Zhang and Chen in Museum of Northern Arizona Bulletin
60,
> although the reference to its description by "Zhang & Li, 1996" is missing
> from their bibliography. So what gives? 1996 or 1998?
>
> If that isn't wacky enough, the following article
>
> Zhang Yuguang & Li Jianjun, 2001. "A study on new materials of
> _Mamenchisaurus jingyanensis_," in Deng Tao & Wang Yuan, eds.,
_Proceedings
> of the Eighth Annual Meeting of the Chinese Society of Vertebrate
> Paleontology_, China Ocean Press, Beijing: 35-39 [in Chinese with English
> summary].
>
> notes: "In 1997, another new species of _Mamenchisaurus_ was found in
> Jingyan, Sichuan Province. _Mamenchisaurus jingyanensis_ developed in
Sichuan
> Basin in the early part of the Late Jurassic. ..." This clearly indicates
> that Mj hadn't yet been found in 1996. Typo? Anyone have anything more
> definite on this species?