The Oligochaeta belong to the phylum Annelida, the segmented worms. Their best-known representatives are the earthworms, which are restricted to the Lumbricidae family in Germany, but comprise several families worldwide. They are important ecosystem engineers that decompose and distribute organic material in soil, thus regulating the carbon cycle and ensuring soil fertility. As the second important group of decomposer communities, Enchytraeidae (potworms) also belong to the Oligochaeta group. Depending on the ecosystem, their role in the soil is just as important as that of earthworms, but they work on a smaller scale due to their smaller body size. The research focus of the Oligochaeta section is on the community composition of earthworms and potworms in Central European ecosystems.