Abstract
The present research has as it main purpose the sistematic revision of the bivalve assemblages from the lower part of Corumbataí Formation, Passa Dois Group, Permian of Paraná Basin, Brazil. This study will be the base for the bioestratigraphic refinement previously proposed by Rohn (1984) and for the proposition of an evolutive model of the bivalve faunas from Paraná Basin during permian…