The increased use of X-ray computed tomography and comparable analysis and documentation techniques in geosciences and biosciences over the past 20 years has not stopped at macro- and micropalaeontological objects. Combining modified (or rarely used) micropalaeontological processing techniques with other analysis (SEM, X-ray CT, UV-light documenting etc.) on microfossils (e.g. isolated skeletal elements of invertebrates and vertebrates) and macrofossils (e.g. articulated material from fossil lagerstätten), the overall results on biodiversity and palaeobiological are often comprehensive and outstanding.
In the keynote, the author will present and illustrate this with a few examples. Diversity in the selection and application of different methods and techniques is the key to promising and innovative new results.

We compare ostracod communities from two tufa-bearing freshwater environments near Jena (Thuringia, Central Germany): a modern spring-fed stream in the Pennickental and an early Holocene tufa sequence in the Plinz valley. Both sites represent low-order fluvial systems influenced by carbonate-rich groundwater, but they differ in their underlying lithologies, with dominating Muschelkalk at Pennickental and Buntsandstein at Plinz. In total, 19 ostracod species were recorded in the modern stream, whereas the fossil association consists of 11 species.

The early Holocene Plinz profile reveals a succession of three faunal zones reflecting changing aquatic habitats: (1) a plant-rich, fast-flowing brook with cold, oligotrophic water; (2) a shallow pond behind a tufa barrier with stable, nutrient-richer conditions; and (3) a spring-proximal shallow stream. Dominant species include Candona weltneri and Cavernocypris subterranea, indicating cold climate and changing habitat conditions after the Pleistocene-Holocene transition.

The modern Pennickental assemblages are structured by habitat type: spring ponds, waterfalls, ponded zones, and cascading streams. Flow-adapted and eurythermal species such as Eucypris pigra and Ilyocypris inermis dominate. Cluster and PCA analyses suggest temperature, current velocity, groundwater chemistry (especially alkalinity and sulfate), and vegetation cover are key environmental drivers. Species-environment relationships are consistent between fossil and modern datasets, supporting the ecological stability of many non-marine ostracods over millennial timescales. Nevertheless, different recent and fossil ostracod associations point to changing environments by climatic and anthropogenic factors. Our results demonstrate how modern analogues can refine paleoecological interpretations and provide insights into freshwater responses to past climate transitions.

A common method to assess the inner structure of a fossil, a litho- or a bioclasts are thin sections. However, producing thin sections requires the destruction of the examined object, rendering it unavailable for subsequent studies. Moreover, the number of sections that can be obtained from one sample or object is limited, making quantitative analyses difficult.

Herein, we introduce an advanced methodological solution for this issue. A methodological combination of virtual micro-CT cross-sections with a modified point counting approach allows for straightforward and non-destructive identification and quantification of the examined sample.

We demonstrate the benefits of this method through a pilot study examining the quantitative biological composition of calcareous rhodolith matrices from the Arctic Svalbard archipelago. These calcareous matrices can be composed of one or more crustose coralline algal taxa, as well as a mixed assemblage of various invertebrate encrusters. Due to their unique skeletal structure, these biological components can usually be clearly identified in micro-CT scans.

Virtual cross cutting of scanned matrices, quantification of their taxonomic compositions via point counting and subsequent analyses via binomial regression models revealed bathymetrically influenced proportional differences of the rhodoliths.

The Miocene (Serravallian) Öhningen Maar in southern Germany is one of the most famous Konservat-Lagerstätten. In addition to its abundant plants and vertebrate fauna, the soft-bodied biota preserved in Öhningen is diverse, including various insects, aquatic arthropods, and arachnids. While the Öhningen Maar is often regarded as a single deposit in the literature, it is imperative to recognize that there are notable differences between the two separate outcrops. Not only are there variations in sedimentology, modes of preservation of the soft-bodied fossils, and fossil diversity at the outcrop scale, but these elements can also vary within a few centimetres of the same exposure. Part of this variation can be attributed to changing depositional environments and seasonality, but modern weathering and historical collections bias may also play significant roles. However, understanding the correlative nature of these proxies is in its infancy. Here we present new data from sedimentological, petrographic, paleontological, geochemical, and SEM-EDS analyses which showcase the importance of a multiproxy approach to the understanding of this convoluted deposit. The aim is to provide improved clarity onto the paleoecological and taphonomic questions that have plagued the Öhningen Maar for decades.