To date, more than 110,000 species of arachnids have been described worldwide. They include groups as diverse as web spiders, weavers, scorpions, pseudoscorpions and mites (including ticks). Arachnids are a very old taxon, as they colonized the earth more than 400 million years ago. The research focus of the Arachnida section is on a suborder of mites, the moss mites (Oribatida).
Oribatids can be found in almost all terrestrial habitats from the tropics to the Antarctic and have even colonized the marine littoral, bogs and fresh water. Numerous species have adapted to life on tree trunks, bark and in lichens growing on trees. However, the largest number of species and individuals is found in the soils of temperate latitudes, where up to 200,000 individuals/m² can be found in the humus layer of forest soils. Within the decomposer community, oribatids are of great importance for soil fertility. Their diet consists mainly of dead plant parts, fungal hyphae and spores as well as algae and bacteria. Their feeding activity stimulates the growth of microfauna.
The Arachnida section focuses on the study of the oribatid fauna of peatlands and on dispersal mechanisms of moss mites (wind dispersal, aquatic dispersal, active dispersal).
