Biostratigraphic significance of lower Paleozoic microfaunas from eastern Canada
Chitinozoan studies recently carried out in the Appalachian Forelands and St. Lawrence Platform National Geoscience Mapping Program (NATMAP) project have confirmed the regional biostratigraphic value of a number of chitinozoan species and led to a better documentation of their stratigraphic and geographic distribution in eastern Canada. The typical Darriwilian microfaunas first described from the Table Head Group of western Newfoundland and containing Conochitina chydaea are now recognised in the Riviere Ouelle Formation at Les Mechins, Gaspe Peninsula. In the Upper Ordovician successions of the St. Lawrence Platform at Neuville and in the Charlevoix area, Quebec, Conochitina primitiva is indicative of the multidenspre-americanus graptolite zonal range, Hercochitina duplicitas of the americanus Zone, and Hercochitina spinetum and Acanthochitina cancellata characterize the ruedemanni  lower spiniferus zonal interval. The occurrence of Cyathochitina vaurealensis and Hercochitina crickmayi in turbidite d...