Janus Pannonius Múzeum Évkönyve 38 (1993) (Pécs, 1994)

Természettudományok - Nógrádi, Sára–Uherkovich, Ákos: The Trichoptera fauna of the lake Balaton and its catchment area (Hungary)

40 Hydroptila dampfi Ulmer. - This hydroptilid was discovered in Hungary by ANDRIKOVICS and ÚJHELYI (1983). Later it was also found in Balaton (NÓGRÁDI 1986), and in several further waters (UHERKOVICH and NÓGRÁDI 1990). H. dampfi Ulmer colonizes artifical lakes and ponds very quickly, thus it also occurs in some recently created fish-ponds (Fig. 7). Phryganea bipuncta Retz. - Bodrogszegi (NÓGRÁDI and UHERKOVICH 1988), Hejőkürt, Oszlár (UHERKOVICH, NÓGRÁDI 1990), Tihany (NÓGRÁDI 1989). Oxyethira flavicornis Pict. The first Hungarian occurence was recorded by NÓGRÁDI (1985). Later it became known from the following localities: Nyékládháza (NÓGRÁDI and UHERKOVICH 1988), Hosszúvíz (NÓGRÁDI and UHERKOVICH 1992), Balatonmagyaród and Mezőtúr (UHERKOVICH and NÓGRÁDI 1990). Orthotrichia angustella McL. - It was mentioned by NÓGRÁDI (1986) as a new member of the Hungarian fauna from South Hungary (Kisdobsza). All the other known occurence are situated around Balaton and in the catchment area of Marcal river (UHERKOVICH, NÓGRÁDI 1988). (Fig. 8). Characterization of some caddisfly localities 1. Along the upper branches of the Zala river and its tributaries alpine caddisfly communities have developed. The quick running waters are not yet polluted, thus their fauna show an undisturbed situation: the species diversity is very high, several taxa are still living here which became rare in different Hungarian water courses during this century because of the pollution. As we mentioned: 26 species occur here which were not recorded in other parts of the catchment area. Some of them only inhabit this part of Transdanubia and the mountains in NE Hungary, eg. Ptilocolepus granulatus Pict., Chaetopteryx rugulosa Kol., Agapetus fuscipes Curt., Wormaldia occipitalis Pict., Hydropsyche guttata Pict., Plectrocnemia brevis McL., Oligotricha striata L., Athripsodes bilineatus L. etc. The biotops of the species listed above are very strongly endangered by human activities. Some biotops have been destroyed by the inundation of stream valleys creating fishing ponds. Others were regulated, thus their fauna became poorer. The waters of further streams are polluted by artifical fertilizers, domestic refuse waters and insecticids. Consequently a considerable part of the indigenous species have died out, only few taxa having wide ecological tolerance could survive. 2. The water of Zala river is rather polluted. Accordingly its fauna is very poor and uniformized. 3. The composition of caddisfly community of Balaton is relative diversified. The dominant species are characteristic for stagnant waters, most of them are common all over the country and can be also dominant in dead waters (backwaters of larger rivers, lakes, artifical fish-ponds). The composition of the communities are depending on the chemical conditions of the waters. It is known that the water quality of Balaton differs site by site. Our examinations have also pointed out the importance of these differences for the Trichoptera fauna. The most diverse fauna was registrated in the Sajkod Bay west from the Tihany Peninsula. More than 10.000 specimens of 40 species were captured here, amongst them there were several interesting taxa (see also Tab. 2). Interesting species of the lake Balaton are the follows: Lype phaeopa Hagen, Erotesis baltica McL., Agraylea multipunctata Curt., Ceraclea riparia Albd., Phryganea bipuncta Retz., Oxyethira flavicornis Pict., and Hydroptila dampfi Ulmer. The latter species was also mentioned in the previous entry. The fauna in other sites around the lake is similar but a little poorer in species and specimen number (Fonyód, light trap and personal samplings on few sites). 4. The caddisfly community of the artifical water of Kis-Balaton was not so rich comparing the diverse caddisfly fauna of Balaton. This water surface was formed only five years before our studies started. Thus the fauna is still permanently growing. During the year of the studies (1988) 36 species were captured (see Table 4), so the evolution of the aquatic fauna was in an advanced stage. The question wheather the pollution of Zala river will modify the chemical conditions of the water in a negative way and how the toxical pollutions will accumulate must be the topics of further investigations. Rare species were not captured here, the dominance of two species is outstanding (Ecnomus tenellus Ramb 49.33 %, Leptocerus tineiformis Curt. 22.56 %). We have to note that the dominance of Ecnomus tenellus Ramb. is very high in almost all sites of the lake (see Tables 1-4). 5. Another type of waters can be found in the southern part of the catchment area. In the lowland of Belső-Somogy there are some small wooded marshlands and small unpolluted creeks. Our light trap worked at Somogyszob (Table 5) and the species composition resulted from our personal samplings is illuminating examples for this type. The fauna is diversified but individual, the number of the species are not high owing to the small extension of these biotops. Some rare species are characteristic for this type of waters: Limnephilus subcentralis Brau., Holocentropus dubius