A new Burgess Shale–type assemblage from the “thin” Stephen Formation of the southern Canadian Rockies

Researchers have discovered a new Burgess Shale-type fossil assemblage in the 'thin' Stephen Formation near Stanley Glacier, Kootenay National Park, Canada. This marks the first finding of such fossils in this formation, expanding the known temporal and geographic range of the Burgess Shale biota. Unlike previous discoveries linked to paleotopographic features like the Cathedral Escarpment, this assemblage was preserved in a distal ramp setting without evidence of an escarpment. The low-diversity assemblage includes eight new soft-bodied taxa, notably the anomalocaridid Stanleycaris hirpex n. gen., n. sp., and suggests restrictive paleoenvironmental conditions. The study implies that similar assemblages may be common in the regionally widespread 'thin' Stephen Formation.

Caron, J.-B., Gaines, R. R., Mángano, M. G., Streng, M., & Daley, A. C. (2010). A new Burgess Shale–type assemblage from the “thin” Stephen Formation of the southern Canadian Rockies. Geology, 38(9), 811–814. https://doi.org/10.1130/g31080.1