Arthropod Trace Fossils of the Upper Lower Cambrian Gog Group,Southern Rocky Mountains of Canada

The upper lower Cambrian Gog Group in the southern Rocky Mountains of Canada displays a high diversity and abundance of arthropod traces. Four ichnogenera, Cruziana, Diplichnites, Monomorphichnus, Rusophycus, and “Indeterminate Arthropod Scratches” are discussed, with a total of 17 different ichnospecies, as follows: Cruziana billingsi Fillion and Pickerill, 1990, Cruziana irregularis Fenton and Fenton, 1937, Cruziana jenningsi Fenton and Fenton, 1937, Cruziana navicella Fenton and Fenton, 1937, Cruziana omanica Seilacher, 1970, Cruziana pectinata Seilacher, 1994, Cruziana penicillata Gibb, Chatterton, and Pemberton, 2009, Cruziana plicata Crimes, Legg, Marcos, and Arboleya, 1977, Cruziana tenella Linnarsson, 1871, Diplichnites twelvetreesi (Chapman, 1928), Monomorphichnus bilinearis Crimes, 1970b, Monomorphichnus lineatus Crimes, Legg, Marcos, and Arboleya, 1977, Rusophycus eutendorfensis (Linck, 1942 Linck, O. 1942. Die spur Isopodichnus. Senckenbergiana, 25: 232–255. [Google Scholar]), and Rusophycus unilobus (Seilacher, 1970 Seilacher, A. 1970. Cruziana stratigraphy of “non-fossiliferous” Palaeozoic sandstones. In Crimes, T. P. and Harper, J. C. (eds.), Trace Fossils. Seel House Press, Liverpool, 447–476. [Google Scholar]). Three new ichnospecies, i.e., Cruziana caputinclinata isp. nov., Rusophycus subnotous isp. nov., and Diplichnites obliquus isp. nov., are proposed, described, and illustrated. The ichnofauna collected from three localities (Lake O'Hara, Mount Babel, and Redoubt Mountain) are predominantly Cruziana. Evidence of nutrient-rich substrates containing microbially induced sedimentary structures and the ichnospecies present confirm that the trace fossil bearing strata are part of the Cruziana ichnofacies and were deposited in a fully marine basin between fair weather wave base and storm wave base.