Janus Pannonius Múzeum Évkönyve 40 (1995) (Pécs, 1996)

Természettudományok - Nógrádi, Sára–Uherkovich, Ákos: Trichoptera communities of the river Fekete-Körös in Hungary

S. NÓGRÁDI & Á. UHERKOVICH: TRICHOPTERA COMMUNITIES OF THE RIVER FEKETE-KÖRÖS IN HUNGARY 47 36001989 1990 1991 1992' 1993 1994 320028002400• 2000• 1600• 1200800 400I. I .1 I. 1 1. Щ I. 5 6 7 8 9 10 5 6 7 8 9 10 5 в 7 8 9 10 5 6 7 8 9 10 5 6 7 8 9 10 5 6 7 8 9 10 Fig. 3. The graph of the collected specimens per collecting periods, 1989-1994. 3. ábra. A gyűjtött példányok száma gyűjtési időszakonként, 1989-1994. On the other hand, some species have almost permanent value of dominance, these are the stable member of the community, e. g. Ceraclea dissimilis, Hydropsyche contubernalis, H. modesta, Oecetis ochracea and Ecnomus tenellus. All of them are wide-spread and common species of the Great Hungarian Plain. Role of aquatic transport There are some species in the Trichoptera community of this biotope, which do not belong to this local fauna. These species - Glossosoma boltoni, Cheumatopsyche lepida, Mystacides azurea and Oecismus monedula have mountainous character and they live in quick running, unpolluted rivers and streamlets, mainly in the higher regions of the Carpathian Basin. All of them are rare member of the Hungarian fauna. We suppose that their larvae or pupae were swept away by the water in the upper reaches of Fekete Körös (from the Romanian, mountainous reaches), where the velocity of the river is quicker. These species may live there in a larger number and sometimes their preimaginal forms can be swept away and carried down to lower parts of the river's system. Then they hatch there and can fly onto the light of the trap. Thus these species are not authentic member of the caddisfly community in the Hungarian reach of Fekete-Körös, but only vagrants. Comparision of Trichoptera communities of some larger rivers in Hungary The composition of caddisfly communities of five larger rivers was studied during the last ten years. More than 300,000 specimens were captured and determined