Taxanomy, genetic and autecology of larval Drusinae

Larval Drusinae (Insecta: Trichoptera) are excellent bioindicators due to their high indication weight (up to 4), their sharply-defined longitudinal zonation patterns in running waters and their specific feeding modi. In addition, Drusinae larvae are cold-adapted inhabitants of higher altitude streams and brooks and are very sensitive for ecological scenarios associated with climate change. This high bioindication potential, however, can only be applied when identifications are possible to species level. Unfortunately, this is not the case in central Europe (= Austria, Germany and Switzerland), where the larval stages of six Drusinae species remain unknown.The first aim of this project is therefore to construct a larval key encompassing all 24 central European species. Information on adult specimens stored at national biogeographic data bases (e.g. ZOBODAT at Linz, Upper Austria) will enable us to collect eggs from adults in copula and larvae of hitherto unknown species at the appropriate places and times. Subsequently, the eggs of previously identified egg-laying females will be reared in the laboratory; this will provide us with the morphological information necessary to describe the hitherto unknown larvae and to construct the key. A further work package - molecular genetics and protein electrophoresis - will support the morphological module and provide additional data on taxa that cannot be differentiated morphologically. The genetics and electrophoresis module will also help to test traditional and new phylogenetic hypothesis, to resolve contemporary species grouping concepts, to evaluate generic relationships within the Drusinae and to reconstruct colonization centers and possible routes of dispersial. Rearing the eggs over a range of different constant temperatures will yield information on upper and lower temperature thresholds of embryonic development. Such data sets provide valuable basic information for early warning systems on climate-induced threats to high mountain biodiversity. They will also enable the evaluation of climate change scenarios as highlighted by GLORIA-Europe and EURO-limpacs.

Larval Drusinae (Insecta: Trichoptera) are excellent bioindicators due to their high indication weight (up to 4), their sharply-defined longitudinal zonation patterns in running waters and their specific feeding modi. In addition, Drusinae larvae are cold-adapted inhabitants of higher altitude streams and brooks and are very sensitive for ecological scenarios associated with climate change. This high bioindication potential, however, can only be applied when identifications are possible to species level. Unfortunately, this is not the case in central Europe (= Austria, Germany and Switzerland), where the larval stages of six Drusinae species remain unknown.The first aim of this project is therefore to construct a larval key encompassing all 24 central European species. Information on adult specimens stored at national biogeographic data bases (e.g. ZOBODAT at Linz, Upper Austria) will enable us to collect eggs from adults in copula and larvae of hitherto unknown species at the appropriate places and times. Subsequently, the eggs of previously identified egg-laying females will be reared in the laboratory; this will provide us with the morphological information necessary to describe the hitherto unknown larvae and to construct the key. A further work package - molecular genetics and protein electrophoresis - will support the morphological module and provide additional data on taxa that cannot be differentiated morphologically. The genetics and electrophoresis module will also help to test traditional and new phylogenetic hypothesis, to resolve contemporary species grouping concepts, to evaluate generic relationships within the Drusinae and to reconstruct colonization centers and possible routes of dispersial. Rearing the eggs over a range of different constant temperatures will yield information on upper and lower temperature thresholds of embryonic development. Such data sets provide valuable basic information for early warning systems on climate-induced threats to high mountain biodiversity. They will also enable the evaluation of climate change scenarios as highlighted by GLORIA-Europe and EURO-limpacs.