MAYFLIES (EPHEMEROPTERA) AND STONEFLIES ( PLECOPTERA) OF THE NATURE PRESERVE SVATOJURSKY-SUR

In the nature reserve Svatojursky Sur (Podunajska nizina lowland) we h ave recorded 14 species of mayflies (Ephemeroptera) and 9 species of s toneflies (Plecoptera). The mayflies Siphlonurus armatus, Paraleptophl ebia werneri and especially Arthoplea congener belong to the most valu able taxons. Today they are found especially on the Sur pond, while in the recent past they probably occurred in Sur marshes and bogs. In th e stagnat waters of the lowland reserve prevail northern species of no rth-Central European diversity, while in running waters the south-Cent ral European species are represented more significantly. Species impov erishment of the reserve is the result of strongly negative anthropoge nic pressure in this region (pollution and drainage of tributaries).