Malacological characteristics of the Middle to Upper Pleistocene transitional interval (MIS 7-5) observed in the Batajnica locality (Serbia)

The Batajnica loess section is one of the most complete Middle and Late Pleistocene records known in the Vojvodina region (Serbia). The main aim of the malacological investigations was to study the latest Middle Pleistocene cold interval and to see how the mollusc successions reacted to the climate changes during the cold-warm transition. The deposits which belong to the upper part of pedocomplex V-S2, V-L2 loess and partly to the V-S1 soil were sampled. The penultimate glacial loess V-L2 of the Batajnica site corresponds to the cold interval Marine Isotope Stage (MIS 6). The molluscs indicate moderate or sometimes warm climate and dry or moderate steppe-like environment composed of adjacent mosaics of drier and humid habitats. The mollusc complexes of V-S2 soil (MIS 7c), V-L2 loess (MIS 6) and V-S1 paleosol (MIS 5e) show almost the same species composition, which suggests the existence of a comparatively moderate or warm climate during the late Middle Pleistocene cold interval. In contrast, the mollusc complexes (MIS 6) from Western and Eastern Europe have less species and few individuals compared with the Batajnica section. Comparison with the late Middle Pleistocene mollusc associations from the northern and southern margins of the FruÅ¡ka Gora Mountain confirms its environmental originality. The northern side of the mountain was characterized by a humid and relatively colder environment than the other areas of the Vojvodina region (Batajnica, Irig and Ruma). The mollusc fauna obtained in the Batajnica site suggests that this adjacent area represented a refugium for the thermophilous and arid tolerant species where they were able to survive during the cold periods of the Pleistocene and thus confirms the hypothesis of P. Sümegi.