Supplementary material from "A new ankylosaurine dinosaur from the Judith River Formation of Montana, USA, based on an exceptional skeleton with soft tissue preservation"

Published on 2017-04-27T14:16:51Z (GMT) by
The terrestrial Judith River Formation of northern Montana was deposited over an approximately 4 Myr interval during the Campanian (Late Cretaceous). Despite having been prospected and collected continuously by palaeontologists for over a century, few relatively complete dinosaur skeletons have been recovered from this unit to date. Here we describe a new genus and species of ankylosaurid dinosaur, <i>Zuul crurivastator</i>, from the Coal Ridge Member of the Judith River Formation, based on an exceptionally complete and well-preserved skeleton (ROM 75860). This is the first ankylosaurin skeleton known with a complete skull and tail club, and it is the most complete ankylosaurid ever found in North America. The presence of abundant soft tissue preservation across the skeleton, including <i>in situ</i> osteoderms, skin impressions and dark films that likely represent preserved keratin, make this exceptional skeleton an important reference for understanding the evolution of dermal and epidermal structures in this clade. Phylogenetic analysis recovers <i>Zuul</i> as an ankylosaurin ankylosaurid within a clade of <i>Dyoplosaurus</i> and <i>Scolosaurus</i>, with <i>Euoplocephalus</i> being more distantly related within Ankylosaurini. The occurrence of <i>Z. crurivastator</i> from the upper Judith River Formation fills a gap in the ankylosaurine stratigraphic and geographical record in North America, and further highlights that Campanian ankylosaurines were undergoing rapid evolution and stratigraphic succession of taxa as observed for Laramidian ceratopsids, hadrosaurids, pachycephalosaurids and tyrannosaurids.

Cite this collection

M. Arbour, Victoria; Evans, David C. (2017): Supplementary material from "A new ankylosaurine dinosaur from the Judith River Formation of Montana, USA, based on an exceptional skeleton with soft tissue preservation". The Royal Society.

https://doi.org/10.6084/m9.figshare.c.3757232.v1

Retrieved: 19:03, Nov 19, 2017 (GMT)