pˌækɪsˌɛfɐləsˈɔːɹˈiːni ɪz ðə mˈoʊst ɐdvˈænst ɡɹˈuːp ɪn pˌækɪsˌɛfɐləsˈɔːɹiə ænd ɪz mˌeɪd ˌʌp ʌv nˈɔːɹθ ɐmˈɛɹɪkən mˈɛmbɚz.
Pachycephalosaurini is the most advanced group in Pachycephalosauria and is made up of North American members.