1. Beaty Centre for Species Discovery and Palaeobiology Section, Canadian Museum of Nature, P.O. Box 3443, Station D, Ottawa, Ontario, K1P 6P4, Canada,
2. Department of Earth Sciences, 2115 Herzberg Laboratories, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
3. Department of Biological Sciences, CW 405 Biological Sciences Building, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada,