MACROZOOBENTHOS OF THE MORAVA RIVER BASIN AND TRIBUTARIES OF THE MORAVA

The authors compared the species composition of aquatic insects in the streams and rivers of the Small Carpathians and Zahorie region (the M orava river basin). They discovered considerable differences in the se ttlement of these regions caused by their different physiographic char acteristics. For assessment of sozological localities significance a b iosozology index was suggested. With respect to the occurrence of most endangered, vulnerable, and rare species the middle part of the river Rudava appears to be most valuable. The occurrence of the following s pecies has been confirmed there: Heptagenia flava, Brachycercus harris ellus (Ephemeroptera), Taeniopteryx nebulosa, Periodes dispar, Isopten a serricornis (Plecoptera), Aphelocheirus aestivalis (Heteroptera), Di xa nubilipennis, Dixa nebulosa, Atherix ibis (Diptera). The authors re commended very strict preservation measures particularly in this regio n.