Sharks in local rivers and lakes

During the early Permian, Central Europe was at times covered by great lakes. Higher positions in the food chain, right up to apex predators, were occupied in open water by stem-group sharks. The partly catfish-like shape of these xenacanthids indicates that they were more impressive for their strength than their speed. Nevertheless, they were able to strike quickly. The spine on the back of the head has a defensive function, because even a Bohemiacanthus has to struggle to reach its length of about one meter and until then is threatened by other Xenacanthids. The larger it was, the more "palaeoniscoids" fish (Paramblypterus) or branchiosaurid amphibians (Apateon) it could prey on. Small crustaceans (ostracods), clams (cf. Anthraconaia) and cockroaches (Anthracoblattina) have been documented in the Manebach excavation in the Thuringian Forest, as well as the volcanic influence or the stromatolitic limestone crusts on dead wood in the water.

digital painting, 2022

Trümper, S., Vogel, B., Germann, S., Werneburg, R., Schneider, J. W., Hellwig, A., Linnemann, U., Hofmann, M., & Rößler, R. (2023): Decoding the drivers of deep‐time wetland biodiversity: insights from an early Permian tropical lake ecosystem. Palaeontology, 66(3), e12652. https://doi.org/10.1111/pala.12652