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Nasutoceratops described



Ben Creisler
bcreisler@gmail.com

A new paper:

Eric K. Lund, Scott D. Sampson & Mark A. Loewen (2016)
Nasutoceratops titusi (Ornithischia, Ceratopsidae), a basal
centrosaurine ceratopsid from the Kaiparowits Formation, southern
Utah.
Journal of Vertebrate Paleontology (advance online publication)
http://www.tandfonline.com/doi/full/10.1080/02724634.2015.1054936
DOI:10.1080/02724634.2015.1054936

The skull and associated postcrania of Nasutoceratops titusi, a basal
centrosaurine ceratopsid from the Upper Cretaceous (Campanian)
Kaiparowits Formation of Grand Staircase–Escalante National Monument,
southern Utah, are herein described. Autapomorphies of this taxon
include: an ectonaris that comprises 75% of preorbital skull length;
pneumatic nasals; a hyper-robust premaxilla–maxilla contact; a
double-faceted, medial flange on the maxilla contributing to the hard
palate; and unique supraorbital horncores that are anterolaterally
directed, anteriorly curved, torsionally twisted, and relatively
enormous. A Bayesian analysis, the first conducted for ceratopsians,
is coupled with a parsimony phylogenetic analysis of Centrosaurinae,
with both analyses recovering Nasutoceratops as the sister taxon to
Avaceratops lammersifrom the late Campanian of Montana. Nasutoceratops
titusi provides insights into the origins of Centrosaurinae and
suggests the existence of a previously unknown clade of short-snouted,
long-horned centrosaurines that we here hypothesize to have originated
in the southern Western Interior Basin of North America.