A turbidite sequence within the Twitya Formation (Windermere Supergroup) in the ackenzie Mountains, northwestern Canada, has yielded an assemblage composed of simple centimetric annuli and discs, which are interpreted as biogenic and referred to Nimbia occlusa Fedonkin, Vendetta? sp., and Irridinitus? sp. They occur below a glaciomarine diamictite about 2.5 km below the base of the Cambrian, and they may represent the oldest Ediacaran fossils now known. The find has implications for models that relate the evolution of the Ediacara fauna to the waning of the Varanger glaciation.