Spec-Dinovember Day 12: Number-ceratops, a ceratopsid with multiple horns
Not to be confused with a rhinoceros of similar name, Bicerorhinus motocephalus is a pachyrhinosaurin centrosaur closely related to Stellasaurus. Found on the west coast of Laramidia, these dinosaurs are separated from their more famous eastern relatives by the rising Rocky Mountains. They can be found in what will one day become British Columbia, roaming the valleys between the mountains and coastal volcanic chains. Weighing in at 2 tons, they are rather average for a derived centrosaur in size and morphology save for their laterally paired nasal horns. No other ceratopsid shows this condition and it's quite uncertain as to how their's came to be.
------------------------------------------------------------------------------
This was the prompt I was looking forward to because ceratopsids are my favorite dinosaurs! I kicked around a couple ideas for this dinosaur, one where it has an extra horn behind each eye like in Psittacosaurus sibiricus, one in which it actually had no horns so I could name it Aceratops or some variation, but I settled on two nose horns. A neat little bit of trivia, ceratopsids ancestrally only had the brow horns, and the chasmosaurines and centrosaurines independently evolved nasal horns. But because they were independetly acquired they are structurally different. In chasmosaurines the nasal horn is an epiossification, like those on the frill, that fuses to the nasals during growth. In centrosaurines it's an outgrowth of the nasals, which are paired, so there is a suture that splits the nasal horn down the middle! as the animal ages this suture fuses, and it fuses in a distinctive way: from the tip downward. So what if they never fused? well, there'd have to be some more steps to separate the halves but that was the idea anyway