Janus Pannonius Múzeum Évkönyve 34 (1989) (Pécs, 1990)

Természettudományok - Nógrádi U., Sára–Uherkovich, Ákos: The Trichoptera fauna of the Zselic Downs, Hungary

THE TRICHOPTERA FAUNA OF THE ZSELIC DOWNS, HUNGARY Sára U. NÓGRÁDI and Ákos UHERKOVICH Abstract. 5964 males and 10 877females of 84 Trichoptera species were collected by sweeping, lamp and light trap at 37 sites. The complete list is given with field data (localities, dates, number of individuals) and literature data. Short characterization and some comments on rare species are presented. Quantitative data are given in tables. Introduction From the Zselic Downs, lying in the middle of South Transdanubia, only few caddisfly data have been known until recently. Neither the Fauna Regni Hungáriáé (Mocsáry 1900), nor Pongràcz (1914) mentioned any Trichoptera species from here. The first data made reference to some Hydropsyche (Újhelyi 1982). In the 1980s further papers were published on the Trichoptera fauna of South Transdanubia which included several species from this area (Nógrádi 1986 1988, Nógrádi and Uherkovich 1985 Nógrádi et al. 1985). Geomorphology, hydrography The Zselic Downs is a hilly region amongst the Mecsek Mountains, the Drava Flatland and the Inner (Belső-) and Outer (Külső-) Somogy. A dense network of valleys cuts the low quaternary surface. The maximum elevation does not reach 400 m a. s. 1. In spite of this fact in many places the region looks mountainous. The slopes of valleys are often steep and a large part of this area is covered by old, natural (or close to natural) forests. The vegetation was treated in a few short papers, and recently in a larger work (Borhidi 1984). The water network comprises small brooklets and streams. A part of them runs to the river Kapos bordering the Zselic Downs on the north. Others run to the south (system of Almás and Bükkösd Stream), and reach the river Drava. Many small streams dry out from time to time, e. g. in the very dry years of 1983 and 1984. In 1983 almost all brooklets dried out for months in the western and northern parts of the area. The water quality of the small streams is satisfactory. Some larger streams (Almás, Bükkösd and Surján Streams, Baranya Canal) are moderately or highly polluted. The Baranya Canal sometimes is rather a drain-pipe than a water-course. On the eastern and southern parts of the Zselic Downs several fish ponds have been developed decades or years ago. The waters of some of these is not polluted. In others intensive fish breeding has been established. The water quality of these ponds sometimes is very poor, mostly in high summer the oxygen content decreases almost to zero. Along the margin of the ponds ordinary zonal vegetation is formed. The water of streams and ponds usually has basic reaction. The pH is between 8-9, and the conductivity is relatively high in some larger streams (high natural ion concentration together with pollution). Method and material Some of the specimens are deposited in the collection of Hungarian Natural History Museum (Budapest), mostly from old collectors. The bulk of the material is in the collection of Janus Pannonius Museum (Pécs) and was collected in the end of the 1970s and in the 1980s, by the authors and their light traps. Some specimens had been captured by L. Ábrahám (Kaposvár), who has handed over these caddisflies for publication, for which the authors express their most sincere thanks to him. We have material from 37 sites of the region (Fig. 1), which occupy 15 quadrats of 100 sq. km of the UTM grid map (Fig. 2). Three light traps have been erected in the Zselic Downs for trichopterological purpose. At Kaposfő, along the upper branches of Kapos River a light trap was erected about 100 m from the water. It functioned in the years of 1985 and 1986 with shorter and longer interruptions. The trap was handled by T. Tömösváry. 251 males and 623 females of 37 species were captured during these years, among others Platyphylax frauenfeldi Brau., Crunoecia irrorata Curt., Notidobia ciliaris L. and Brachycentrus subnubilus Curt. Hydropsyche females comprised more than half of the material. Other domináns species are discussed later on. Not too far from this site, at Lipótfa, a very successful light trap functioned in the years of 1986 and 1987. About 100-150 m from the trap a small but permanent brooklet ran and north from it there is a chain offish ponds, whereat a huge material was captured: 1461 males and 3626 females (altogether 5087 specimens) A Janus Pannonius Múzeum Évkönyve 34 (1989): 15-38. Pécs, Hungária, 1990.