Triceratops sub-adult growth stage

[bh480@scn.org]

From: Ben Creisler
bh480@scn.org

A paper that apparently has not been mentioned yet on the 
DML. The pdf is free.

FUJIWARA Shin-ichi and TAKAKUWA Yuji (2011)
A sub-adult growth stage indicated in the degree of 
suture co-ossification in Triceratops.
Bulletin of Gunma Museum of Natural History(15):1-17
http://www.gmnh.pref.gunma.jp/research/no_15/bulletin15_1.
pdf

A Triceratops specimen, GMNH-PV 124, excavated from the 
Hell Creek Formation, South Dakota, is composed of nearly 
complete skull elements, axial skeleton, and partial limb 
elements. Co-ossification of the skull elements and the 
scapula-coracoid contact are not finished and hence the 
specimen is sub-adult. However, co-ossification has been 
started or finished among the occipitals, supraorbital 
horn cores, and parietal, between the rostrum and 
premaxillae, between the epinasal and nasals contacts, 
the first to third cervical vertebrae, and sacral 
vertebrae.

More  content for this Japanese Journal with links to 
free pdfs can be viewed at
http://www.gmnh.pref.gunma.jp/research/no_15/