TRILOBITES OF THE DONALD FORMATION:

Donald Formation, Early Cambrian, Nevadella Zone, Dogtooth Range, Southern Canadian Rocky Mountains, British Columbia.

Trilobites:

Cirquella nummularia Fritz, 1993

Nevadia? sp.

Bradyfallotaspis? sp.

Comments:

    As far as we know, the genus Cirquella has never been found complete. In fact, there are no known reported pygidia as far as we can tell. This is also true of Geraldinella spp. (which are found in age equivalent rocks of the Mural formation). See also: Mural Formation.

References:

Lieberman, B. S. (2002) Phylogenetic analysis of some basal early Cambrian trilobites, the biogeographic origins of the Eutrilobita, and the timing of the Cambrian radiation. Journal of Paleontology, Vol. 76, No. 4, pp. 692-708.

Fritz, W. H. (1993) New Lower Cambrian olenelloid trilobite genera Cirquella and Geraldinella from southwestern Canada. Journal of Paleontology, V. 67(5), pp. 856-868.