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Abstract

Abstract.A high resolution taxonomy and classification framework is developed for the representatives of the calcareous benthic foraminiferal family Bolivinoididae; this family consists of 24 species assigned to three genera. This new classification includes data pertaining of the test ultrastructure, ornamentation and porosity, which are obtained with the aid of careful and extensive study of the specimens under the scanning electron microscope. Two new taxa are described: Bolivinoides antiquum -n. sp. and Swiecickina -n. gen. A biostratigraphical framework consisting of eleven biozones based on bioevents given by species of the genera Bolivinoides and Swiecickina is developed for the middle Santonian-Maastrichtian stratigraphical interval; its resolution is more than double when compared to those of the previously developed biostratigraphical frameworks based on the representatives of this group.