Lower Ordovician trilobites from the Baumann Fiord Formation, Ellesmere Island, Arctic Canada

Abstract

Sections through member B of the Baumann Fiord Formation on the Bache Peninsula, Ellesmere Island, Arctic Canada, contain a range of lithofacies indicating deposition in shallow subtidal settings above storm wave base. Macrofossils are generally rare, but low-diversity trilobite-dominated faunas occur in a section near Sanddöla Creek. The only other fossils common in the collections are poorly preserved gastropods. All of the trilobite species are apparently new, and four are formally named: Licnocephala sanddoelaensis, "Peltabellia" baumannensis, Bolbocephalus ellesmerensis, and Ceratopeltis bachensis. The species Ceratopeltis forteyi is introduced for material previously described from North Greenland. Rare additional species of Licnocephala and Jeffersonia are reported in open nomenclature. The trilobites occur in three stratigraphically and lithologically distinct associations, with species diversity ranging from two to four. Closest comparisons of the trilobite species all indicate that member B should be assigned to the Tulean Stage of the Ibexian Series. Rananasus Cullison, 1944, is placed in synonymy of Bolbocephalus Whitfield, 1890.