Ostracods and the middle Miocene evolution of the Bugojno Basin (Bosnia and Herzegovina)

Abstract

In the present study, the taxonomical and palaeoecological interpretations of non-marine ostracod assemblages from the Gracanica opencast coal mine are summarised. The results revealed three different ostracod assemblages within a 40-m succession. The oldest ostracod assemblage from the lower part of the section consisted primarily of pioneer species Fabaeformiscandona cf. pokornyi, Vestalenula cylindrica, Paralimnocythere rostrata, Cyclocypris ovum and Mediocypris cf. candonaeformis. Determined ostracods indicated a very shallow environment, with a low water energy. The second ostracod assemblage with the dominant species Cypridopsis cf. biplanata in the middle part of the succession corresponded to a shallow littoral environment, rich in vegetation with gradual water deepening. The third ostracod assemblage occurred in the upper part of the Gracanica section. Generally, marly sediments of the upper part of the succession contained abundant, thin, transparent and very poorly preserved ostracod valves that belonged to Candonidae gen. et sp. indet. taxon typical for a lake environment.