Bravoceratops, new chasmosaurine ceratopsian from Late Cretaceous of Texas

[Ben Creisler <bcreisler@gmail.com>]

From: Ben Creisler
bcreisler@gmail.com


A new online paper:

Steven L. Wick & Thomas M. Lehman (2013)
A new ceratopsian dinosaur from the Javelina Formation (Maastrichtian)
of West Texas and implications for chasmosaurine phylogeny.
Naturwissenschaften (advance online publication)
DOI: 10.1007/s00114-013-1063-0
http://link.springer.com/article/10.1007/s00114-013-1063-0


Bravoceratops polyphemus gen. et sp. nov. is a large chasmosaurine
ceratopsid from the lowermost part of the Javelina Formation (early
Maastrichtian) of Big Bend National Park, TX, USA. B. polyphemus has a
distinctive narrow snout, a long fenestrate frill, and a fan-shaped
median parietal bar with a midline epiparietal on its posterior
margin, as well as a symmetrical depression on its dorsal surface at
the nexus of the parietal rami. This depression is interpreted to be
the attachment point for a second midline epiparietal. This parietal
morphology is distinct from that exhibited by Anchiceratops or
Pentaceratops. The posterior midline epiparietal in B. polyphemus and
its bifurcated quadratojugal–squamosal joint are features shared with
the most derived chasmosaurines, Torosaurus and Triceratops. The
combination of primitive and derived traits exhibited by B.
polyphemus, and its stratigraphic position, is compatible with the
gradual transition from basal, to intermediate, to derived
chasmosaurines observed throughout the western interior of North
America, and with phylogenetic analysis, which suggests that
Bravoceratops may be closely related to Coahuilaceratops.