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Regaliceratops, new chasmosaurine from Alberta, Canada

Ben Creisler

A new online paper:

Caleb M. Brown & Donald M. Henderson (2015)
A New Horned Dinosaur Reveals Convergent Evolution in Cranial
Ornamentation in Ceratopsidae.
Current Biology (advance online publication)
DOI: http://dx.doi.org/10.1016/j.cub.2015.04.041

pdf (it was open access for me when I tried):



•A new horned dinosaur, Regaliceratops, is described based on a nearly
complete skull
•It exhibits large nasal and small postorbital horns, and large frill
•A derived chasmosaurine, the new animal shows centrosaurine-like
display features
•Evidence for evolutionary convergence in horned dinosaur display is documented


Ceratopsid (horned) dinosaurs are an iconic group of large-bodied,
quadrupedal, herbivorous dinosaurs that evolved in the Late Cretaceous
and were largely restricted to western North America. Ceratopsids are
easily recognized by their cranial ornamentation in the form of nasal
and postorbital horns and frill (capped by epiossifications); these
structures show high morphological disparity and also represent the
largest cranial display structures known to have evolved. Despite
their restricted occurrence in time and space, this group has one of
the best fossil records within Dinosauria, showing a rapid
diversification in horn and frill morphology. Here a new genus and
species of chasmosaurine ceratopsid is described based on a nearly
complete and three-dimensionally preserved cranium recovered from the
uppermost St. Mary River Formation (Maastrichtian) of southwestern
Alberta. Regaliceratops peterhewsi gen. et sp. nov. exhibits many
unique characters of the frill and is characterized by a large nasal
horncore, small postorbital horncores, and massive parietal
epiossifications. Cranial morphology, particularly the
epiossifications, suggests close affinity with the late
Campanian/early Maastrichian taxon Anchiceratops, as well as with the
late Maastrichtian taxon Triceratops. A median epiparietal
necessitates a reassessment of epiossification homology and results in
a more resolved phylogeny. Most surprisingly, Regaliceratops exhibits
a suite of cranial ornamentations that are superficially similar to
Campanian centrosaurines, indicating both exploration of novel display
morphospace in Chasmosaurinae, especially Maastrichtian forms, and
convergent evolution in horn morphology with the recently extinct
Centrosaurinae. This marks the first time that evolutionary
convergence in horn-like display structures has been demonstrated
between dinosaur clades, similar to those seen in fossil and extant