Swiss Journal of Geosciences

, Volume 103, Issue 2, pp 155–162

Species concept in North American stegosaurs


DOI: 10.1007/s00015-010-0020-6

Cite this article as:
Carpenter, K. Swiss J Geosci (2010) 103: 155. doi:10.1007/s00015-010-0020-6


The plated thyreophoran or stegosaurian dinosaur Stegosaurusarmatus was named in 1877 by Marsh for fragmentary remains from the Morrison Formation (Upper Jurassic) of Colorado, USA. Subsequent discoveries from the same formation in Wyoming and Colorado (USA) have been assigned to separate stegosaurian genera and species, but most of these are no longer considered valid. More recently, a partial stegosaurian skeleton from Wyoming was named Hesperosaurusmjosi. However, the validity of this genus has been questioned recently, raising the question: how much osteological difference among stegosaur taxa is needed to separate genera from species? The question is examined vis-à-vis species and genus recognition in other dinosaurs, including iguanodonts, lambeosaurine iguanodontids, chasmosaurine ceratopsians, tyrannosaurid theropods, and diplodocid sauropods. The basis for taxonomic distinction is largely philosophical: if the species are morphologically distinct enough, they should be treated as separate genera. Based on these criteria, Hesperosaurus mjosi is a distinct taxon.


Stegosaurus Hesperosaurus Morrison Formation Late Jurassic Palaeontological species Taxonomy 

Institutional abbreviations


Denver Museum of Natural History (now the Denver Museum of Nature & Science), Denver, CO, USA


Hayashibara Museum of Natural History, Okayama, Japan


Sauriermuseum Aathal, Switzerland


United States National Museum (now the National Museum of Natural History, Smithsonian Institution), Washington, DC, USA


Yale Peabody Museum of Natural History, New Haven, CT, USA

Copyright information

© Swiss Geological Society 2010

Authors and Affiliations

  1. 1.Prehistoric MuseumUtah State University-College of Eastern UtahPriceUSA