S. Mahunka szerk.: Folia Entomologica Hungarica 49. (Budapest, 1988)

PLACES, DATES AND METHODS OF INVESTIGATION Collections were made 22 times in the valley of the Apátkut Stream, between April and November in 1984. During these collections the whole length of the stream was covered. Collections made in frequency of 1-2 weeks provided the opportunity to reach phenological conclusions. At the hunting box of Apátkut (Fig. 1) a HgL light-trap of 125 W was operated, with the permission of the Nature and Environmental Conservancy Institute. Our results are based on imago investigations (370 Ephemeroptera and 300 Plecoptera individuals) and by the map-like representation of the localities. Reports of the visits to the spot and the identified material can be found in the scientific collection of Department of Systematic Zoology and Ecology of the Eötvös Loránd University. After surveying the area a work-map was made using a basis map on which localities of each species were marked. Identifications were made by the help of taxonomic books and articles dealing with the given group (ILLIES, 1955, KIS, 1974, LANDA, 1969, ÚJHELYI 1959, ELLIOTT-HU M PESCH, 1983, MALZACHER, 1984, SOWA, 1971, MÜLLER-LIEBENAU, 1969). Dates of collections: 13.03, 17.03, 02.04, 12.04, 17.04, 30.04, 03.05. 10.05, 17.05, 19.05, 25. 05, 30.05, 12-13.06, 13- 14.07, 17.07, 06-07.08, 16- 17.08, 4-5.09, 12. 09, 0910.10, 18-19.10, 30.10, 1-2.11, 13.11. 20.11, 1984. Between 13th Nov. and 20th Nov. Ephemeroptera and Plecoptera could not be collected either by light trapping or field collecting. SPECIES OBSERVED AND ECOLOGICAL NOTES Ephemeroptera Ephemera danica (Müller, 1764): 12-13.07. 1 ç, 01.06. 1 13.06. 1 ó", 17.05. 1 6, 08.06. 1 6, Larvae are silt-dwelling, flying season in May-June. Baetis rhodani (Pictet, 1843-45): 12.06. 8 6, 5 ç, 12- 13.07. 33 6. Ördögbánya-Hunting box. Larvae are abundant along the whole length of the stream. Flying imagos were captured between Ördögbánya and the hunting box. Larvae and imagos were determined on the basis of the taxonomic book written by MÜLLER-LIEBENAU (1969). Cloeon dipterum (Linné, 1761): 06. 10. 6 subimagos, 25. 05. 1 S, and 15 subimagos. Standing water-dwelling species, specimen were found at the hunting box of Apátkut. Procloeon bifidum (Bengtsson, 1915): 23.05. 1 S, 1 hunting box. Centroptilum luteolum (Müller, 1776): 08.06. 2 6 and 1 hunting box. Epeorus sylvicola (Eaton. 1885): 17. 05. 3 3 and 6 <j>, hunting box, 01. 06. 1 6, 08. 06. 3 <5, ördögbánya. Rhithrogena semicolorata group: 30.04. 1 6, house with chimney, 03.05. 1 <j>, Ördögbánya, 12. 06, 10 6, 12. 07. 2 6, hunting box. 9 species of this group occur in Europe. It is sure that the specimens captured by the author do not belong to the denominating species, Rhithrogena semicolorata. Exact identification can only be carried out by having a large material collected along other streams of the Visegrád Mountains. Larvae are abundant in the whole Apátkut Valley. Ecdyonurus (Heptagenia) lateralis group: 10.05. 2 «5, 2 hunting box, 08.06. 1 6, 1 <j>, fore-part of Szentlászló Valley. Exact identification is in progress. Ecdyonurus starmachi (Sowa, 1971): This species was relatively late, in the submountain region of the Carpathians. It belongs to the Ecdyonurus helveticus group. It proved to be new for the Hungarian fauna; so male and female body parts important in identification have been drawn. Larvae and imagos are the most abundant between Ördögbánya and the hunting box. 17.07. 6 6, 2 ç, hunting box, 06-07. 07. 1 6, 1 <j>. Ördögbánya. Ephemerella ignita (Poda, 1761): 12-13. 07. 5 <j>, hunting box, 06-07. 08. I 6, 3 <j>, hunting box. Larvae are the most abundant between ördögbánya and the hunting box. Caenis horaria (Linné, 1758): 12-13. 07. 5 i. The most abundant standing water-dwelling Caenis species in Hungary. Larvae develops in the retained ponds behind the hunting box. Caenis robusta (Eaton, 1884): It was recently observed in several places (ANDRIKOVICS, 1988). Presumably it is a standing water-dwelling species that may occur in every kind of standing waters, from lowland alkaliflats to stagnant waters. 12-13. 07. 3 6, hunting box.