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Rhinorex, new hadrosaurid from Upper Cretaceous of central Utah (free pdf)

Ben Creisler

A new online paper:

Terry A. Gates & Rodney Scheetz (2014)
A new saurolophine hadrosaurid (Dinosauria: Ornithopoda) from the
Campanian of Utah, North America.
Journal of Systematic Palaeontology (advance online publication)

A new hadrosaurid is described from the Upper Cretaceous Neslen
Formation of central Utah. Rhinorex condrupus gen. et sp. nov. is
diagnosed on the basis of two unique traits, a hook-shaped projection
of the nasal anteroventral process and dorsal projection of the
posteroventral process of the premaxilla, and is further
differentiated from other hadrosaurid species based on the morphology
of the nasal (large nasal boss on the posterodorsal corner of the
circumnarial fossa, small protuberences on the anterior process,
absence of nasal arch), jugal (vertical postorbital process),
postorbital (high degree of flexion present on posterior process), and
squamosal (inclined anterolateral processes). This new taxon was
discovered in estuarine sediments dated at approximately 75 Ma and
just 250 km north of the prolific dinosaur-bearing strata of the
Kaiparowits Formation, possibly overlapping in time with Gryposaurus
monumentensis. Phylogenetic parsimony and Bayesian analyses associate
this new taxon with the Gryposaurus clade, even though the type
specimen does not possess the diagnostic nasal hump of the latter
genus. Comparisons with phylogenetic analyses from other studies show
that a current consensus exists between the general structure of the
hadrosaurid evolutionary tree, but on closer examination there is
little agreement among species relationships.