S. Mahunka szerk.: Folia Entomologica Hungarica 43/1. (Budapest, 1982)

Species Sh 1979 (Dp.c. Bw ) Wf Sh 1980 (Dp.c. Bw ) Wf Metadelphax propinqua Fieb. _ 0.17 _ _ Ribautodelphax albostriatus Fieb. 0.69 3.56 0.17 0.49 3.82 Struebingianella elegantula Boh. 0.25 Toya minuscula Horv. 0.35 Other Delphacidae 0.63 1.58 1.29 0.61 0.31 5.46 Dictyopharidae: Chanitus pannonicus Germ. 0.10 0.33 0.17 Cercopidae: Lepyronia coleoptrata L. 0.89 0.69 3.86 2.15 1.36 2.19 Neophilaenus infumatus Hpt. 0.16 0.17 N. lineatus L. 0.77 0.99 1.40 0.25 0.55 Philaenus spumarius L. 0.19 0.14 0.25 Issidae: Ommatidiotus incospicuus Stal. 2.32 0.23 1.09 0.49 Tettigometridae : Tettigometra atrata Fieb. 0.55 Tropiduchidae: Trypetimorpha fenestrata Costa 0.17 Sh: Sand hills; Bw: Between sand hills and wind furrows; Wf: Wind furrows. in the traps on the sand hills, which were in the wind furrows on the basis of the sucked samples until this time. The biocenometric samples were taken generally in the same morning hours, so if we suppose that there is a daily migration among certain populations between to two terrains, then we can explain these differences. Of course, we have to make further detailed investigations about these suppositions. 66 species were collected on the sand hills and 71 in the wind furrows by the two methods during the 4 years. This means 84 species in the whole area. We also collected the following species with seep net: Macrosteles fieberi Edw., Muellerianella fairmairei Perr., Ribautodelphax imitans Rib, and Stictocephala bisonia F. Together with them and the earlier mentioned species, collected with Malaise trap 94 species have been found in the area until this time. Of course, it does not mean that this number of leafhopper species constantly inhabit this the area. A part of them must have been there only temporarily, as guests. On the basis of the results we must make detailed investigations on the populations of 30 species in the wind furrows and 31 species on the sand hills further. VI. The spatial changes of the rates of leafhopper populations with different ecological valence, as an indicative measure of the successional processes The investigated area was grazed sporadically before 1976. The typical species composition of the indigenous vegetation changed considerably because of the anthropogenous and zoogenous influences. It can be already seen during the 5 years after the protection against grazing, that the typical plant compositions have continuously been re-established. We can see the expansion of meso-xerophilous plant species (BODROGKÖZI and FARKAS, 1981). The phytophagous insect community must have followed the successive changes of plant associations. Investigations of the rates of primary consumer groups with different ecological valence resp. the changes of them provide a good opportunity of us to control primarily this supposition. According to this, the leafhopper populations were divided into four groups: dry grassland specific (group I), xerophilous (group II), indifferent of dry grasslands (group III) and not characteristic for dry grasslands (group IV).