S. Mahunka szerk.: Folia Entomologica Hungarica 54. (Budapest, 1993)

the density of fungicolous species increases in the autumn. In the cooler and more rainy western part (Western Transdanubia) of Hungary species missing from the Great Plain become dominant (Dely-Draskovits and Babos 1976\b). Habitat aspects The number of fungicolous Diptera species and their abundance show a gradual increase from the open grasslands (steppe habitats) towards the open and then closed stages of forests. Therefore we can find differences in the species composition of Diptera communities and in the number of individuals of a given species within one habitat (Dely-Draskovits and Babos 19767b). Interactions among the Diptera species living in fungi The Diptera species developing in the fruiting bodies do not form constant species associations. We did not find any species, which were constantly accompanying each other. The Diptera developing in fungi eat the fruiting body of the fungi, therefore they are obligate or facultative mycophages. Species differing in their feeding methods may occur in any fruiting bodies at the same time. The basis of their presence is always the fungus, which provides the flies with food and shelter, and they are associated with other species only as place and food competitors. Besides these species zoophagous and parasitic species occur as well, which feed on the fungivorous species (Dely-Draskovits 1976). Economic importance of Diptera We studied very carefully which species consume edible fungi species, which are important as food resources for humans, and as export goods. We studied the extent of damage caused by the different species as well. There are species, which always occur, and do not show an particular host-preference, their abundance is exceptionally high, and they occur every year in high numbers. 25% of the species reared from our samples belong to this type. 75 % of species occurred only sporadically, but they might become very abundant occasionally (Dely-Draskovits and Babos 1974). The edible mushrooms are most infected in September, the proportion of infected specimens might be more than 70% (Dely-Draskovits and Babos 1976/c). Nature conservation aspects The results of our research on funguicolous Diptera showed that every single macrofungus living in the grass or moss layer of different habitats must be regarded as an important microhabitat, which may serve as a potential microhabitat for many populations of insect species. Approximately 30% of the Hungarian Diptera species might develop in fungi. Therefore from the edible mushrooms growing in natural habitats, only the young and non-infected specimens should be collected (i.e. the ones suitable for human consumption). The fruiting bodies of inedible or poisonous mushroom species, which are more numerous than the edible species, should be left untouched, and hence both the fungi and the attached animal association attached to them are protected.