Janus Pannonius Múzeum Évkönyve 43 (1998)( Pécs, 1999)

Természettudományok - Ábrahám, Levente–Kovács, Tibor: A report on the Hungarian alderfly fauna (Megaloptera: Sialidae)

54 A JANUS PANNONIUS MÚZEUM ÉVKÖNYVE 43 (1998) Fig. 5.: Seasonal activity graph of Sialis species in Hungary 5. ábra: A magyarországi Sialis fajok szezonális aktivitási diagramja MEINANDER (1962) published some differences in the nineth sternite forms of the subgenital plate of the females. Although, this key did not seem to be very characteristic in distinguishing both species. Several specimens of both sexes were extremely close to each other. On the other hand, we did not manage to identify the larva belonging to Sialis morio in our collected material by the key published by KAISER (1977); larvae of Sialis lutaria were at least as variable as the adults. We could not find any differences from phenological and ecological points of view in Hungary. The distribution of Hungarian species is shown on UTM map. As it can be seen Sialis lutaria is the commonest species, however, the other common species, Sialis fuliginosa is also widespread and fairly frequent in Hungary. Sialis morio and Sialis nigripes identified in this decade are supposed to be rare species. After evaluating distribution and localities we can conclude that Sialis lutaria is more vagile in habitats, as the species lives both in standing water and in running water, while Sialis fuliginosa occurs mainly in different types of running water (brooks, springs, rivers). Having few data on Sialis morio they can not be evaluated from this point of view. Collecting larva of Sialis nigripes in the system of Tisza River is of considerable importance since is the newest locality in the area and gives valuable information on its habitat. The existence of this species that may live in calcareous water, as cited in different literatures (PLANT 1997) can not be proved by Hungarian data. It is more widespread as it has been thought up till now (POPOV 1981, JOHNSON et al. 1995). Alderfleis can be trapped by traditional collecting methods (light trap, Malaise trap etc.) only with great difficulty. For example: there are few specimens in recorded material collected by light traps or Malaise traps. In the course of personal collecting the number of specimens vary in accordance with the time allotted to it. While some of the collectors take about a dozen material by netting from different localities others take only one specimen. That is why the activity graph from available data is unsatisfactory. So seasonal activity graph like Fig. 4 was drawn by showing the days and months of their appearance marked along the time line (ÁBRAHÁM 1998).