Fields and meadows around Dolenje Mokro Polje are underlain by the Middle Miocene (Badenian) marly limestones. After annular plowing of the fields, shells and casts of fossil gastropods and bivalves, originating from these marly limestones, come to the surface. In some specimens are observed traces of predation (boreholes), that were decided to be explored more detail and based on their shape tried to determine the predator. We also documented the abundance of the drilled shells. The focus of the research is on the gastropod Turritella. As part of the diploma thesis, two fields were examined; the first (locality A) is 20 m2 large, the second (locality B), measures 52.5 m2. From the area A, all fossil shells and their casts were systematically collected. At the locality B, the emphasis has been on collecting unfragmented (or less fragmented) shells of the gastropod genus Turritella. The species composition of the assemblage was determined by comparison with material stored at the Slovenian Museum of Natural History. Twelve different species were determined, the most common among them is Turritella turris. Some selected specimens were examined to determine the possible predators by observing the boreholes under the Scanning Electron Microscope. Finally, the obtained results were compared with the position and shape of the boreholes in recent Turritella. The most common predators of turritellids are the naticid gastropods, but some borings also belong to muricids, although no fossil muricids have been found at neither of the localities. The most common drilling position is in the central part of the shell, between the fourth and the seventh whorl. Similar, also recent turritellids are mostly drilled in the central part of the shell. Compared with the recent turritellids, there are clear differences in the thickness, size and the relief of the shell.
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