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New chancelloriids from the Early Cambrian Sekwi Formation with a comment on chancelloriid affinities

  • Robert D. Randell (a1), Bruce S. Lieberman (a1), Stephen T. Hasiotis (a1) and Michael C. Pope (a2)


Articulated scleritomes of the chancelloriids Archiasterella fletchergryllus new species and Chancelloria cf. eros Walcott, 1920 are described from the Early Cambrian (Branchian) Sekwi Formation, Mackenzie Mountains, Northwest Territories, Canada. Early diagenetic, microbially mediated lithification has resulted in unusual three-dimensional preservation of the body surface, which potentially allows consideration of the evolutionary affinities of these enigmatic organisms. Sclerites are mounted on short stalks of the integument, connected to the undersurface of the central disc, and are external to the body surface.



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