Science, Tech, Math › Animals & Nature Dinosaur Profile: Stygimoloch Print Onlookers view a 68 million-year-old Stygimoloch skull outside the Fox studios which will be auctioned along with other dinosaurs fossils and pre-historic creatures by Guernsey's Auction House June 16, 2004 in New York City. Mario Tama/Getty Images Animals & Nature Dinosaurs Herbivores Basics Paleontologists Carnivores Dinosaurs & Birds Marine Reptiles Prehistoric Mammals Amphibians Birds Habitat Profiles Mammals Reptiles Insects Marine Life Forestry Evolution View More By Bob Strauss Bob Strauss Science Writer B.S., Cornell University Bob Strauss is a science writer and the author of several books, including "The Big Book of What, How and Why" and "A Field Guide to the Dinosaurs of North America." Learn about our Editorial Process Updated on March 07, 2019 Name: Stygimoloch (Greek for "horned demon from the river Styx"); pronounced STIH-jih-MOE-lock Habitat: Plains of North America Historical Period: Read More Stegoceras By Bob Strauss Late Cretaceous (70-65 million years ago) Size and Weight: About 10 feet long and 200 pounds Diet: Plants Distinguishing Characteristics: Moderate size; unusually large head with bony protuberances About Stygimoloch Stygimoloch (the genus and species name of which, S. spinifer, can be loosely translated as "horned demon from the river of death") wasn't nearly as terrifying as its name implies. A type of pachycephalosaur, or bone-headed dinosaur, this plant-eater was fairly lightweight, about the size of a fully grown human being. The reason for its intimidating name is that its bizarrely ornamented skull evokes the Christian conception of the devil--all horns and scales, with the slightest hint of an evil leer if you look at the fossil specimen just right. Why did Stygimoloch have such prominent horns? As with other pachycephalosaurs, it's believed that this was a sexual adaptation--males of the species head-butted each other for the right to mate with females, and bigger horns provided a valuable edge during rutting season. (Another, less convincing theory is that Stygimoloch used its gnarly noggin to butt away from the flanks of ravenous theropods). Apart from these displays of dinosaur machismo, though, Stygimoloch was probably fairly harmless, feasting on vegetation and leaving the other dinosaurs of its late Cretaceous habit (and small, cowering mammals) alone. Within the past few years, there has been an intriguing development on the Stygimoloch front: according to new research, the skulls of juvenile pachycephalosaurs changed drastically as they aged, much more so than paleontologists had previously suspected. Long story short, it turns out that what scientists call Stygimoloch may have been a juvenile Pachycephalosaurus, and the same reasoning may well apply to another famous thick-headed dinosaur, Dracorex hogwartsia, named after the Harry Potter movies. (This growth-stage theory applies to other dinosaurs as well: for example, the ceratopsian we call Torosaurus may simply have been an unusually elderly Triceratops individual.) Cite this Article Format mla apa chicago Your Citation Strauss, Bob. "Dinosaur Profile: Stygimoloch." ThoughtCo, Aug. 28, 2020, thoughtco.com/stygimoloch-1092980. Strauss, Bob. (2020, August 28). Dinosaur Profile: Stygimoloch. Retrieved from https://www.thoughtco.com/stygimoloch-1092980 Strauss, Bob. "Dinosaur Profile: Stygimoloch." ThoughtCo. https://www.thoughtco.com/stygimoloch-1092980 (accessed April 25, 2024). copy citation