What is Stygimoloch?
{{italic title}} {{speciesbox | fossil_range = [[Upper Cretaceous]] <br/>70{{ndash}}66 mya | image = Berlin Naturkundemuseum Dino Schaedel.jpg | image_upright = 1.1 | image_caption = Reconstructed skull at the Museum für Naturkunde, Berlin | display_parents = 2 | genus = Stygimoloch | parent_authority = [[Peter Galton|Galton]] & [[Hans-Dieter Sues|Sues]], [[1983 in paleontology|1983]] | species = spinifer | authority = Galton & Sues, 1983 | synonyms = * ''[[Dracorex]]''? <small>[[Bob Bakker|Bakker]] et al., 2006</small> }} '''Stygimoloch''' was a plant-eating [[dinosaur]] that had bony spikes and knobs on its skull. This bipedal dinosaur lived during the late [[Cretaceous|Cretaceous period]], about 70 million to 66 million years ago. Like other [[Pachycephalosauria|pachycephalosaur]]ids, Stygimoloch was a [[Bipedalism|bipedal]] [[herbivore]] with an extremely thick skull roof. It had long hindlimbs and small forelimbs. Stygimoloch probably head-butted as a defense and in rivalry. 22% of all domes examined had [[lesion]]s suggesting [[osteomyelitis]]. This is an infection of the bone resulting from [[trauma]]. So pachycephalosaurid domes were probably used in intra-species combat.<ref name=Peterson13>{{cite journal | last1 = Peterson | first1 = JE | last2 = Dischler | first2 = C | last3 = Longrich | first3 = NR | year = 2013 | title = Distributions of cranial pathologies provide evidence for head-butting in dome-headed dinosaurs (Pachycephalosauridae) | journal = PLOS ONE | volume = 8 | issue = 7| page = e68620 | doi = 10.1371/journal.pone.0068620 | pmid = 23874691 | pmc = 3712952 | bibcode = 2013PLoSO...868620P | doi-access = free }}</ref> ''Stygimoloch'' fossils were first discovered in North America, in [[Montana]] and [[Wisconsin]]. The first was discovered in [[Hell Creek Formation|Hell Creek]], Montana and was named in 1983 by Peter M. Galton, a British paleontologist and Hans-Dieter Sues, a German paleontologist. == Young Pachycephalosaurus? == After Dracorex was discovered and Stygimoloch was discove