Somogyi Múzeumok Közleményei 9. (1992)

Uherkovich Ákos- Nógrádi Sára: 1992: Some data to the Trichoptera fauna of Drava River, Hungary Néhány adat a Dráva magyarországi szakaszának trichoptera faunájához

SOME DATA TO THE TRICHOPTERA FAUNA OF DRAVA RIVER, HUNGARY ÁKOS UHERKOVICH-SARA NOGRADI Abstract. 21 041 caddisfly specimens belonging to 44 species were collected at Szentborbás, South Hungary. Quantitative list of material is given. Some comments on rare and characteristic species are presented. 51 specimens (40 males, 11 females) of Platyphylax frauenfeldi Brau, were collected here, its 7 Hungarian localities are known at recent days. Introductions Relatively few data have been published till recent days about Trichoptera of the larger Hungarian rivers. Chantaramongkol

(1 983) studied and published a large caddisfly material deriving from a light trap nearby Danube, Verőce, north of Budapest. Authors also have a very large but unvaried material from the southern part of Hungarian Danube, about 99.5 per cent of this material consists of Hydropsyche species and it is still undetermined. Few data were published from the Tisza and Körös river, from the Great Hungarian Plain {Uherkovich'and Nógrádi4990). Earlier no caddisfly material has been collected in any point of the Hungarian branches of Drava river. Drava springs from the Italian Alps, it runs across the southern part of Austria, then it enters Yugoslavia. Later it is frontier river between Yugoslavia and Hungary. Drava joins Danube after 720 km running. Its catchment area covers 40 000 sq. km. Its run is relatively quick carrying much alluvial deposit from the Alps. The Hungarian branches cut themselves 1...2 cm deeper per year as a consequence of control. The most important tributaries are Mura, Rinya and Feketevíz in Hungary. The average water output is about 620 eu. m. per sec. at the discharging into Danube. The maximum average is 875 eu. m. per sec. in June, the minimum one is 400 eu. m. per sec. in February. Drava is the fourth largest tributary of Danube (after Sava, Tisza and Inn). Method and material In 1989 a light trap was erected close to the river Drava, at Szentborbás, со. Somogy (YL08), only few meters from the water (Fig. 1). This trap was fitted by 80 Watt mercury vapour bulb, and it was in function in seven periods from 28th April till 2nd November. The killing and preserving material was aethylenglycol. During some 70 nights 5065 males and 15 976 females, altogether 21 041 caddisfly adults were captured by the trap. More than a third, 8302 specimens were taken between 25th July and 4th August. In April/May and in October/November the quantity was under 1 p. с of the total material (see Table 1 below). Table 1. The quantity of caddisflies captured at Szentborbás in each period. 1. táblázat. A Szentborbáson fogott tegzes anyag az egyes időszakokban. Period Male Female All specimens of caddisflies Per cent of total material April 28-May 7 48 2 50 May 27^June 5 1493 2334 3827 June 28-0uly 6 1862 4137 5999 July 25-August 4 924 7378 8302 August 23-Sept. 1 553 1565 2118 Sept. 22-Oct. 3 88 537 625 Oct. 25-Nov. 2 97 23 120 0.24 18.19 28.51 39.46 10.06 2.97 0.57 altogether 5065 15976 21041 100.0 Altogether 44 species were collected by the light trap during this year (Table 2). The material is deposited in the collection of Janus Pannonius Museum, Pécs, Hungary; 1 male and 1 female of Platyphylax frauenfeldi Brau, is in Malicky's collection, Lunz am See, Austria.