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Abstract

Agnostoid trilobites from the type locality of the middle Cambrian (Series 3, Drumian) Manuels River Formation, Newfoundland, Canada, are described systematically. The fauna consists of 1408 specimens, collected bed-by-bed. The taxa are assigned to the suborders Agnostina and Eodiscina, families Peronopsidae, Ptychagnostidae, Condylopygidae and Eodiscidae, genera Peronopsis Hawle and Corda, 1847, Hypagnostus Jaekel, 1909, Ptychagnostus Jaekel, 1909, Tomagnostus Howell, 1935, Pleuroctenium Hawle and Corda, 1847, and Eodiscus Hartt in Walcott, 1884, and the species Peronopsis fallax (Linnarsson, 1869), Peronopsis scutalis (Hicks, 1872), Hypagnostus parvifrons (Linnarsson, 1869), Ptychagnostus punctuosus (Angelin, 1851), Ptychagnostus affinis (Brøgger, 1879), Ptychagnostus atavus (Tullberg, 1880), Tomagnostus fissus (Lundgren in Linnarsson, 1879), Tomagnostus perrugatus (Grönwall, 1902), Pleuroctenium granulatum (Barrande, 1846) and Eodiscus punctatus (Salter, 1864b). The faunal assemblage is subdivided from base to top into five interval zones, viz. Peronopsis scutalis, Tomagnostus fissus, Ptychagnostus atavus, Ptychagnostus affinis and Ptychagnostus punctuosus zones. The Ptychagnostus punctuosus Zone can be compared regionally and globally. The entire fauna is comparable to that of Baltica and Greenland, which suggests geographic proximity during the middle Cambrian. Pleuroctenium granulatum is endemic to Avalonia and Baltica.