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Abstract

Twenty-four Diptera families are known to develop in an aquatic environment in Central Europe, and approximately half of them were commonly found in springs. However, in most studies only part of the spring community was determined to the species level. Since the use of emergence traps, more information is now available, and species determinations for Chironomidae and Ceratopogonidae were neglected, due to small size, large specimen numbers and difficult taxonomy. Most studies were for the duration of one year, so that long-term data of spring Diptera were lacking. Small size and vermiform morphology are basic adaptations of many dipteran larvae. Morphological variability of Thaumaleidae and Dixidae larvae is low due to their microhabitat. Psychodidae, however, adapted to different microhabitats provide variability of larval morphology. A variety of life-cycle strategies seems to be used by congeners to inhabit the similar ecological niches. Diptera found in springs do not exclusively live in these biotops, but are frequently found under similar environmental conditions, in flood plains along streams. Cutting of riparian forests, draining and amelioration of the meadowlands, may have induced isolation processess, resulting in small taxa with low flight ability, compared with large aquatic insects.