The last centrosaur for this month is one of the most distinctive and recognizable of all ceratopsians – the elaborate Styracosaurus (“spiked lizard”).
Known from Alberta, Canada, about 75 million years ago, it was part of the Centrosaurini branch of the centrosaur evolutionary tree, closely related to both Centrosaurus and Coronosaurus. Many fossils have been found in several different bonebeds, including some nearly complete skeletons with body lengths of around 5.5m (18′).
There was a lot of variation in the frill ornamentation between different Styracosaurus individuals. They could have either two or three pairs of very long spikes at least 50cm long (19″), along with various smaller hooks, knobs, or tab-shaped projections.
The long nose horn was also very variable between specimens, with some pointing slightly backwards, some being straight, and others pointing forwards. Juveniles are known to have had small pointed brow horns which became even more reduced in adults.
Tomorrow we’re moving on to the chasmosaurs, so here’s the centrosaur evolutionary tree:
