The first complete description of the holotype of Brachylophosaurus canadensis Sternberg, 1953 (Dinosauria: Hadrosauridae) with comments on intraspecific variation
Article first published online: 26 MAY 2010
© 2010 The Linnean Society of London
Zoological Journal of the Linnean Society
Volume 159, Issue 2, pages 373–397, June 2010
How to Cite
CUTHBERTSON, R. S. and HOLMES, R. B. (2010), The first complete description of the holotype of Brachylophosaurus canadensis Sternberg, 1953 (Dinosauria: Hadrosauridae) with comments on intraspecific variation. Zoological Journal of the Linnean Society, 159: 373–397. doi: 10.1111/j.1096-3642.2009.00612.x
- Issue published online: 26 MAY 2010
- Article first published online: 26 MAY 2010
- Received 5 February 2009; accepted for publication 9 June 2009
- morphological variation
The holotype of Brachylophosaurus canadensis was collected by C.M. Sternberg in 1936 from the Oldman Formation (Upper Cretaceous) of Alberta, Canada, with a brief description focusing on the cranium following in 1953. A re-description of the holotype skeleton confirms its position as a hadrosaurine dinosaur exhibiting the following unique combination of characters: paddle-like solid nasal crest; posteriorly elongated prefrontal; only the anterior tip of the lacrimal contacting maxilla; extremely elongated anterior maxillary process; and a quadratojugal with a noncrescentic posterior margin variably forming a paraquadratic foramen with the quadrate. Comparison of the holotype with other specimens assigned to the taxon reveals numerous morphological differences. These variable features include the presence/absence of an accessory premaxillary foramen, the number of maxillary/dentary vertical tooth rows, the number of functional teeth per tooth row contributing to the dental occlusal surface, the bones forming the mandibular glenoid, the presence/absence of a nasal foramen, nasal crest morphology, the number of cervical vertebrae, and axis morphology.
© 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159, 373–397.