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Aim: Land use change, such as urbanization and intensification of agricultural practices, poses major threats for biodiversity. We examined whether the composition of freshwater species differs between landscapes dominated by urban, agricultural or more natural structures in a region with a long history of landscape transformation.We determined the differences and characteristics of the dragonfly fauna in relation to major land use categories. We particularly focused on urban land use, as it generally induces a high level of landscape transformation. Location: Germany.Methods: We used distribution data of dragonflies derived from a citizen science database, which was compiled for the German distribution atlas. To analyse whether different land use categories are associated with distinct species compositions, we performed the classification method random forest.Results: Based on dragonfly abundance per grid cell, we identified distinct land userelated assemblages that were separated by two gradients, that is, the level of transformation and a gradient from open land to forest. In particular, urban landscapes possessed a distinct species composition with specific species, all of which were opportunistic and supported by warm climate. They also comprised significantly higher α-diversity than intensive agricultural landscapes. Similar values of γ-diversity over all land use categories implied a countrywide homogenized dragonfly fauna, which is probably caused by historic land use. Main conclusions:Our results indicate that land use is a relevant driver for the composition of freshwater species at the landscape scale. Urban landscapes maintain species diversity better than agricultural landscapes, but they modify the species composition. Additional research on the effects of land use change is required to understand species responses and predict future distributions in a changing world in order to plan sustainable conservation strategies.

1. This study investigates whether cities have the potential of hosting high species diversity of dragonflies (Odonata), a target group in freshwater conservation.2. We reviewed the dragonfly fauna of 30 cities in Central Europe and analysed their species richness compared to the regional species pools in the hinterlands, i.e. estimated the amount of regional diversity represented in cities. In particular, we examined the occurrence of species of conservation concern at the European scale.3. Results revealed that 92.6% of all 81 Central European dragonfly species occurred in cities, as well as 85.7% of 14 species of conservation concern. As expected, assemblages of city species were subsets of the regional species pool and city species richness increased with regional species numbers. Some cities hosted the complete regional species pool.4. Ten species of conservation concern established autochthonous populations and six of them, such as Aeshna viridis and Ophiogomphus cecilia, were abundant at least in single cities.5. We conclude that there is good potential for cities to host high dragonfly diversity and even to promote species of conservation concern. To exploit this potential we recommend city planners to focus on the needs of regionally characteristic species.

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