The study of eight stratigraphic sections at the margin of the semi-enclosed Zsámbék Basin (Hungary) allows the sedimentary anatomy of ooliticbioclastic systems in the Sarmatian of the Central Paratethys to be reconstructed. The mollusc, foraminiferal and ostracod associations indicate that the carbonate systems are Latest Badenian to Late Sarmatian in age. The Lower-Upper Sarmatian deposits are organized in superimposed subaqueous dunes prograding towards the basin on a low-angle ramp. During the Late Sarmatian, the ramp underwent subaerial erosion linked to a moderate relative fall in sea-level. Lagoonal deposits were later formed and microbialnubeculariid-bryozoan-serpulid buildups were emplaced. The 'abnormal' marine conditions of the Sarmatian, conducive to the development of a poorly diversified flora and fauna and dominant non-skeletal grains, are linked to fluctuating salinities, mesotrophic to eutrophic conditions and perhaps high alkalinity.

Research focused on the methodology of the micro-CT device in the foraminifera studies reviewing its advantages and limits. First, the procedure of stable, oriented and removable fixing of foraminifera, washing residue and cuttings in the device was developed, which is fast, cheap, non-destructive and the sample remains re-usable for further investigation. Moreover, a process was developed for foraminifera investigation (e.g., content, amount, identification, description, illustration) in the shortest and simplest way. In the identification of foraminifera as well as in other microfossils group (e.g., radiolaria) the external and internal characteristics together identified the genera, even the species. Additionally, there are several foraminifera species, which are known only from the rock thin sections. The micro-CT was found to be a unique tool for real 3D microscopy and to be able to present the characteristic morphological features when the free movement, rotation or sectioning of the models of the specimens can be performed by interpretation software. However, the biggest advantage of this method is its non-destructive property, which makes it also capable of measuring valuable materials such as holotypes. The relatively small volume analysed and the lack of specific software developed for different micropalaeontological groups are the limits of this method. This visualization technique gives new perspectives in taxonomical studies and in applied micropalaeontology.

Palaeoenvironmental changes in the upper Middle Miocene Central Paratethys were reconstructed by using qualitative and quantitative palaeontological analyses of foraminifera and ostracods, coupled with trace elemental (Mg/Ca) and stable isotope (δ18O and δ13C) analyses of their carbonate skeletons and of gastropod shells. Mean annual air temperatures were estimated using the oxygen isotope composition of contemporaneous rodent teeth. The studied aquatic fossils come from two boreholes in the Zsámbék Basin (northern central Hungary), while the terrestrial ones are from localities in NE Hungary and E Romania. In the studied Sarmatian successions, three zones could be distinguished, based on palaeontological and geochemical results. At the Badenian/Sarmatian boundary, faunal diversity decreased markedly. In the lower zone a transgressive event culminated in a seawater incursion into the semi-open basin system of the Central Paratethys. Stable bottom-water temperature (~15 °C) and variable salinities (20–32 ‰) are estimated for the Early Sarmatian Sea. The faunal changes (notably a strong reduction in biodiversity) occurring at the boundary between the lower and the middle zone can be explained by a sea-level highstand with dysoxic conditions. A relative sea-level fall is documented at the end of this middle zone. After a short regressive event, a marine connection between the Paratethys and the Mediterranean was established at the beginning of the upper zone. This is indicated by an increased microfaunal diversity and the re-appearance of marine Badenian ostracods and foraminifera, which are completely absent from the older Sarmatian series. During the upper zone, the temperatures and salinities are estimated to have fluctuated from 15 °C to 21 °C and from 15 ‰ to 43 ‰, respectively.

Examination of normal pore canals, especially sieve-type pore canals, in living and fossil representatives of ten genera of the family Limnocytheridae, subfamily Timiriaseviinae, has revealed important diversity of structure. These complex pore canals have been studied via high-resolution scanning electron microscopy (the Cartographic Method) and analysed via the application of newly devised indices to assess patterns of consistency and variation in both detailed structure of individual pores and of their distribution on the calcified valve. The timiriaseviine taxa are compared with species of the genera Limnocythere, sub-family Limnocytherinae and Cyprideis (family Cytherideidae). The relationship between the living animal and its aquatic environment is discussed in the light of previous studies and of new evidence herein. The importance of normal pore canals for systematics is highlighted by the recognition and definition of the new tribe Gomphodellini Danielopol, Cabral & Lord nov. tribe, subfamily Timiriaseviinae, family Limnocytheridae.

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