Five benthonic trilobite genera, Lonchocephalus, Welleraspis, Komaspidella, Glaphyraspis, and Coosina, and a planktonic form, Pemphigaspis, occur in burrowed, pelletized carbonate alternating with planar stromatolites. The faunule is the first record of the Crepicephalus Zone in Missouri. The same suite is found in similar facies in the Appalachian region; only one of the benthonic genera, Lonchocephalus is known from rocks of similar age but different facies in the Upper Mississippi Valley.

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