The Late Jurassic Plattenkalk flora of Bavaria, Germany: What about palynology?

The Upper Jurassic Plattenkalk deposits of the Solnhofen Limestone of Bavaria in southern Germany, one of the most productive Fossillagerstatten worldwide, are widely believed to be devoid of palynomorphs or to contain only poorly preserved organic matter. A first palynological study of sediments from several of the Bavarian Plattenkalk outcrops shows clear differences with regard to the quantity and quality of the organic content, which are strongly linked with the sedimentological facies within the Plattenkalk. Partially silicified limestones have not yielded any usable organic matter, whereas laminated, fine- grained limestones contained abundant remains of what appear to be microbial mats (microbialites), and thus support the hypothesis that the limestone originated from the precipitation of calcium carbonate promoted by cyanobacteria. The best preserved and most diverse palynomorph assemblages were obtained from bioturbated shales and bituminous, partially silicified Plattenkalk. Future palynological studies should focus on beds with higher clastic content deposited under higher energy levels, or increase the sample size to obtain statistically relevant amounts of organic material for qualitative and quantitative analyses. There is so far a wide discrepancy between the meager microfossil record and the diversity of terrestrial plant macrofossils preserved in the Plattenkalk beds.