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Chuanjiesaurus: more info



From: Ben Creisler bh480@scn.org
Subject: Chuanjiesaurus--more info

I finally had time to do a rough translation of the 
Chinese description of Chuanjiesaurus. Sorry to report 
that the description is extremely short and provides no 
comparisons with other taxa or  measurements of the major 
elements of the skeleton (or even an estimate of the 
animal's total size). I also had some problems deciphering 
exactly what the authors meant in certain passages (it's 
not clear if some descriptions apply to individual 
vertebra or part of the whole tail, for instance) so I'm 
leery about some details of my current translation (note 
the ??'s). Illustrations of the bones would have helped 
but none were published with the description! Caveats 
aside, here's a bit more info:

Fang, Pang, Lü, Zhang, Pan, Wang, Li & Cheng, 2000.  
Lower, Middle and Upper Jurassic divisions of the Lufeng 
region of Yunnan Province. pgs: 208-214. IN Proceedings of 
the Third National Stratigraphical Conference of China. 
Geological Publishing House, Beijing. 

Chuanjiesaurus ananensis
Description:
Cervical vertebrae vertebral bodies comparatively long, 
opsithocoelous type, lateral depressions comparatively 
shallow,  neural arches low; anterior caudal vertebrae 
procoelous type, towards back part ??distal ball weakly 
developed??, posterior (vertebrae) amphicoelous type, 
height of neural spines becomes lower toward the posterior 
(?end of the tail?), through change from club-shaped to 
plank-shaped; haemal arch forked; scapula proximal end 
markedly enlarged; coracoid nearly oval in form;  ilium 
comparatively large, near semi-circular in form; pubic 
bone expanded, (?expansion) situated middle slanting 
anterior part; ischium (distal end?) not expanded; front 
to hind limb ratio 0.83: 1, ulna to humerus ratio 0.65: 1, 
tibia to femur ratio 0.67 : 1. 

The holotype (Lfch 1001 (Lufeng Museum)) is described 
as "a comparatively complete postcranial skeleton" that 
includes 9 cervicals, 17 caudals, 2 ribs and various 
elements from the limbs and limb girdles. (I'm a bit 
mystified about a piece described as "incomplete skull 
join dorsal vertebra"--an incomplete atlas-axis?) From 
Laochang Jing site, less than 1 km from A'na hamlet and 
about 10 km from Chuanjie village, Lufeng County, Yunnan 
Province; Middle Jurassic Chuanjie Formation.

More info comes from an article in German that appeared in 
March 1999 about dinosaur finds around the village of 
Chuanjie in Yunnan Province. The article is still up on 
the web at the Das Bild website:
http://www.bild.de/service/archiv/1999/mar/05/leute/dino05/
dino05.html
The article mentions three specimens of sauropods and 
provides a photo of part of a skeleton with a leg bone 
described as 1.2 meters long--it's likely that at least 
one (if not all) of the finds represents Chuanjiesaurus 
but the Bild article doesn't give a direct clue and the 
Chinese paper only mentions one specimen.

Of special interest, though, is the photo of a complete, 
articulated theropod skeleton. As far as I know, this is a 
new Middle Jurassic theropod yet to be described. Does 
anybody have info on this mystery "Chuanjie" theropod?  
Note that Betty had a posting about the Chuanjie dinosaur 
graveyard ("China to Build First Dinosaur Park in Yunnan") 
on Feb. 29, 2000--the CNN piece appears to be an update 
for discoveries made after those mentioned in the Bild 
article, though some details were mixed up in the CNN wire 
story (the terms "carnivore" and "herbivore" were switched 
in the text!). The theropod mentioned in the February 
article may be related to the one in the 1999 Bild photo--
if not the same specimen.  

The Chinese paper that includes a description of 
Chuanjiesaurus pegs the Chuanjie Formation as earliest 
Middle Jurassic in age, possibly making it older than the 
Dashanpu (Bathonian-Callovian) fauna (Gasosaurus, 
Shunosaurus, etc.), but that point obviously needs more 
research. The paper does not address the issue as far as I 
can tell, only indicating that the Chuanjie Formation 
immediately follows the Early Jurassic Lufeng Formation 
series locally. Note that the Bild article cites 160 
million years ago as the date, which would be Callovian 
(probably too late). The presence of 25 m-long sauropods 
at such an early date would be of particular interest (see 
translation below).

Here's a rough translation of the German text of the Bild 
article:

First the scientists found only a pair of fossilized 
bones. Now, with chisels and brushes, they're unearthing 
more and more prehistoric giants. A dinosaur graveyard has 
been discovered in China.
The "Jurassic Park" lies near Lufeng in Yunnan Province. 
The first dinosaurs fossils were dug up in 1938  some 
kilometers away. Several years ago paleontologists renewed 
the search and found the graveyard in the soft, red 
sandstone of the Chuanjie rocks. At least a dozen animals 
must have died in this relatively small area 160 million 
years ago.
The researchers have so far unearthed three nearly 
complete skeletons of sauropods. These are the gigantic 
long-necked, multi-ton giant dinosaurs whose steps made 
the earth shake. They were peaceful planteaters. According 
to the discoverer: "Based on the vertebrae and the hip 
bones we can estimate the size.  One of the dinosaurs must 
have been at least 25 meters long. A monster!" In addition 
the researchers dug up the remains of a meat-eating 
dinosaur--it likely comes from the same family as the 
predatory Tyrannosaurus. They also found four snake-necked 
turtles and a row of fish bones.
The dinosaurs' discoverers now are beginning to mount the 
carefully extracted skeletons for museum display, so their 
finds can be marveled at and protected from the elements.