Chelicerata are a basically terrestrial group of invertebrates, including many clades whose representatives have never found an evolutionary way to aquatic live. An exception is made by some spiders and the highly diverse aquatic mites which in inland water habitats are represented by members of numerous different clades having evolved an aquatic or amphibious lifestyle along various evolutionary pathways. For the first time in limnofaunistic bibliography, the present taxonomic knowledge about these different groups of invertebrates is brought together in an overview for the...