Tuesday, December 08, 2015

The Giving of December. Rubeosaurus

Rubeosaurus originally started out as a species of Styracosaurus that was based upon partial skull remains,‭ ‬a partial parietal bone recovered in‭ ‬1928‭ ‬and a slightly more complete second specimen consisting of left and right nasal and horncore,‭ ‬left premaxilla,‭ ‬partial left orbital with horncore and almost complete right parietal with two spikes.‭ ‬The‭ ‬arrangement of spikes was key in identifying the remains as a distinct genus which led to them being named as Rubeosaurus,‭ ‬a reference to the similarity to the spikes you might see on a bush.‭ ‬There are four large spikes that rise up from the back of the neck frill,‭ ‬the centre two being angled so that they point towards one another,‭ ‬while the outer two point out away from the middle.‭ ‬Although not yet known,‭ ‬the skull remains indicate that the horn was very broad at the base,‭ ‬though its length is uncertain.
       There has been speculation that Rubeosaurus‭ (‬Ryan et al‭ ‬2007,‭ ‬referencing the remains as Styracosaurus ovatus‭) ‬may in fact be the adult form of Brachyceratops,‭ ‬a dubious ceratopsian genus established upon the remains of partial juveniles.‭ ‬Normally when an animal has been named twice the first name has priority over the second as well as any further namings.‭ ‬However because Brachyceratops is considered to be highly dubious it has also‭ ‬been‭ ‬figured to be an unsuitable senior synonym due to the incomplete nature of the remains that were used to establish the genus.‭ ‬However because it is so difficult to refer further remains to them,‭ ‬it is difficult to prove a formal connection between Brachyceratops and Rubeosaurus,‭ ‬hence the former still being left as a nomen dubium at the time of writing.

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