In addition, we modified Characters 59 and 61, which describe the epiparietal (ep) morphology at loci ep 2 and ep 3, to include a state that differentiates between rugose, tongue-shaped horncores and greatly elongate, spike-like horncores that, for example, characterize the ep 3 locus in pachyrhinosaurins and some other taxa (e.g., Styracosaurus).
Source: wiktionary