Abstract
Trait‐based approaches have increased significantly in community ecology during the last decade. This is not least because studies on biodiversity–ecosystem functioning relationships became a major topic in ecology. Species' functions in ecosystems are mediated by their traits. For a better understanding of the relationships between environmental drivers, the community composition of organisms and ecosystems functioning, it is crucial to understand how these relationships are mediated by the communities' trait composition. While there are world‐wide efforts to set up trait databases, most have so far focused on plants and species‐poorer taxa such as birds or amphibians. In contrast, for insects, the large number of species makes the gathering of comparable trait data a challenging task. In addition, there is the danger that generic trait information, which is available from common textbooks, may not be sufficient to detect the response of insect communities to environmental change or the consequences of trait changes for ecosystem functioning. One method to overcome this is to take morphometric measurements of species. In this study we measured morphometric traits of a total of 179 Heteroptera species that were sampled by sweep‐netting on a total of 150 managed grassland plots across three regions in Germany between 2008 and 2012. These plots represent the whole range of grassland management intensities from extensively used pastures to mown pastures to intensively managed and fertilized meadows. In this paper we provide a database of mean values of 23 morphometric measures across sex and morphotypes for each sampled Heteroptera species. Morphological traits are assumed to be related to their adaptation and function in the environment. Thus the relative morphometric traits can be used as proxies for ecological features of a species that may affect its performance or fitness. Our database can be used by future trait‐based studies for developing and testing hypotheses of the functional significance of these traits. Examples include studying the functional responses of insect communities to environmental drivers or studying how the change in trait composition affects ecosystem processes.