Acritarchs from the upper Silurian of Argentina: their relationship with Gondwana

In Argentina, the Copo and the Los Espejos formations have yielded palynological assemblages (acritarchs and spores) assigned to the Upper Silurian. There are 149 species of acritarchs and 10 species of spores listed from seven assemblages. In this study, the characteristics of the palynological assemblages are reviewed and the correlations between them are discussed. Wenlockian age is proposed for the acritarch assemblage of the Copo Formation, previously dated as Ludlovian. Los Pozos, Los Azulejitos and Rيo Jلchal assemblages are dated as Ludlovian. Las Aguaditas and Loma de Los Piojos assemblages are of late Ludlovian-Pridolian? age. lynological assemblage of Los Azulejitos indicates an open shelf environment, the assemblages of Las Aguaditas and Loma de Los Piojos indicate a proximal open shelf environment and the Rio Jachal assemblage varied from a deep shelf to a proximal shelf environment. ritarch assemblages of Argentina show close similarities to those from other Gondwanian and Perigondwanian areas (Britain, Spain, France and North Africa). It could be interpreted that the Upper Silurian acritarchs show a cosmopolitan distribution, similar to that of other fossil groups, rather than a latitudinal zonation.