TRILOBITES OF THE LOWER MIDDLE CAMBRIAN POLIELLA DENTICULATA BIOZONE (NEW) OF SOUTHEASTERN NEVADA

Two new genera, Poliellaites and Piochella, and six new species, Eokochaspis? cabinensis, Nyella? plana, Poliellaites gloriosa, Piochella peasleensis, Poliella ovala, and Stephenaspis highlandensis, are described from the Susan Duster Limestone and Log Cabin members, Pioche Shale. Kochaspis Resser, 1935, and Kochaspis liliana (Walcott, 1886) are redescribed based on new material. In addition, several species from the Pioche Shale, that are not addressed in our previous reports are discussed in relationship to existing species and local occurrence. The trilobite diversity of the Poliella denticulata Biozone (new) within the study area is 17 genera and 35 species, occurring in five faunal assemblages.