Abstract
A comprehensive investigation of the gravel bank spider fauna of 10 rivers and streams in the northern parts of the European Alps provided an account of 45 species in 13 families. The most common species were Pardosa wagleri, Erigone atra and Oedothorax agrestis. In combination with six previously published studies on spiders of flood plain habitats, a set of 60 species, that are "common or dominant" on riparian gravel banks, was identified and grouped in four categories: riparian, open land, forest, and euryoecious. Pardosa wagleri, Pardosa saturatior, Pirata knorri, and Oedothorax agrestis were classified as stenoecious riparian species. Altitude, floodplain width and level of human impact had no influence on the number of species recorded in each river section. The stenoecious riparian species do not appear to be suitable indicators for a natural river system, since there is no evidence that their numbers are affected by the artificial reduction in number and size of floodplain gravel banks.