This is the author's accepted manuscript, the published version is available here http://www.mapress.com/zootaxa/2011/f/z02918p028f.pdfThe Early Cambrian olenelline trilobites are a diverse clade that have been the subject of
several phylogenetic analyses. Here, three new species of Bradyfallotaspis Fritz, 1972
(B. coriae, B. nicolascagei, and B. sekwiensis) and one new species of Nevadia Walcott, 1910 (N. saupeae) are described from the Sekwi Formation of the Mackenzie Mountains, Northwest Territories, Canada. In addition, new specimens potentially referable to
Nevadia ovalis were recovered that may expand that species’ geographic range, which
was thought to be restricted to Sonora, Mexico. A phylogenetic analysis incorporating
several olenelline taxa, including Judomia absita from the Sekwi Formation, is also
presented herein. This species has been assigned to various olenelline genera, including Judomia Lermontova, 1951 and Paranevadella Palmer & Repina, 1993. Phylogenetic analysis suggests this species is closely related to Judomia tera Lazarenko, 1960 from
Siberia. This phylogenetic relationship provides further support for the hypothesis that a
close biogeographic relationship existed between Laurentia and Siberia during the
Cambrian
