©Slovenian Entomological Society, download unter www.biologiezentrum.at LJUBLJANA, JUNE 2004 Vol. 12, No. 1: 115-122 XVII. SIEEC, Radenci, 2001 THE TRICHOPTERA (INSECTA) OF THE CSÔRGÔ BROOK IN THE MÀTRA MOUNTAINS (NORTH HUNGARY) Otto KISS Kâroly Eszterhâzy College of Education, Department of Zoology, 3300 Eger, Leânyka u. 6., Hungary Abstract - Larvae and imagines of Trichoptera were collected monthly at five sampling sites along the Narad and Csôrgô brooks from early May to late September 2000. A description of the sampling sites is given together with the temperature, pH, conductivity, and oxygen content of the water. In total, 24 species of Trichoptera were collected and the numbers of individuals/m2 for the sites are also given. Key words: Trichoptera, Matra Mts., Narad brook, Csôrgô brook, Hungary Izvleček - MLADOLETNICE (TRICHOPTERA) POTOKA CSÔRGÔ V POGORJU MÂTRA (SEVERNA MADŽARSKA) Ličinke in odrasle primerke mladoletnic smo od zgodnjega maja do poznega septembra 1. 2000 zbirali mesečno na petih vzorčevalnih mestih vzdolž potokov Narâd in Csôrgô. Opis vzorčevalnih mest vključuje temperaturo, pH, prevodnost in vsebnost kisika v vodi. Skupno smo našli 24 vrst mladoletnic, za posamezna mesta navajamo tudi število primerkov/m2. Ključne besede: Trichoptera, pogorje Matra, potok Narâd, potok Csôrgô, Madžarska Introduction Although there are some data related to the occurrence of various species of Trichoptera in the Csôrgô brook of the Matra Mts. (Ujhelyi, 1974, Olâh, 1965, Kiss O., 1980, 1981), they are from sporadical samplings. The sources, rill sand brooks with andesite and andesite tuff as their base rock provide a habitat for the flora and 115 ©Slovenian Entomological Society, download unter www.biologiezentrum.at Acta entomologica slovenica, 12 (2), 2004 fauna with the Trichoptera as one of the benthos assemblages. So, a survey of the chemical status of water and the qualitative and quantitative study of larvae and imagines of Trichoptera seem to be important for the investigation of this area. The larvae of Trichoptera inhabit the bottom of the brooks in a mosaic-like pattern, which is typical of the brooks of the mountains of medium height (Kiss, 1977, 1999). Material and methods The Csorgo brook is situated in the Western Matra Mts., NW of Matraszentimre. It is formed by the confluence of three smaller brooks, which are called the Narad, Hutahelyi and Gedeon. It is of about 5.5 km in length and flows into the Kovecses brook near Matrakeresztes. The study area is at 660-540 m a.s.l.; i.e. the difference between the heights of the first and last sampling sites is 120 m. Andesite and andesite tuff are typical of this area. The microclimate of the valley is cool and wet, typical of mountains of medium height. The mean annual temperature is between 6°C and 8°C, the mean annual precipitation is 700-900 mm. At a farther distance from the brook beeches (Fagus silvatica L.) can be found. The brook bed is lined with common alder (Alnus glutinosa L. Gartn.) and hornbeam (Carpinus betulus L.) with poor undergrowth and with fern (Polypodium vulgare L.) in places. Larvae and imagines of Trichoptera were collected monthly at 5 sampling sites from early May to late September. For the quantitative study the methods of Kamler and Riedel (1960) and Macan (1958) were used (Schmera and Kiss, 2000). The temperature, pH, conductivity and oxygen content of the water, as well as the air temperature were measured when taking samples. For the identification of larvae Hickin (1967) and Waringer and Graf (1997) were used, while the imagines were indentified using Malicky (1983). The data were evaluated using diagrams, the monthly occurrence of trichopteran species is given with reference to the larva-imagine relationship and the mosaic-like assemblages of larvae in the brook bed. A NuCoSA cluster analysis (Fig. 1.) justifies the similarities and dissimilarities of the sampling sites. Results Description of the sampling sites: Narad brook, beyond the confluence of the three brooks, Nt sampling site, 1600 m from the source, at 660 m a.s.l. The bottom of the brook is covered with large stones. The depth of water is between 3 cm and 5 cm. The brook flows in several branches of a width of 40-50 cm each. Water temperature is 17.9°C in August and 9.1°C in September. Conductivity ranges between 207 ¡uS/cm and 250 ¡LiS/cm, the pH values can be considered constant; they vary from 7.5-7.8. The oxygen content, however, fluctuates to a relatively large extent; it ranges between 4.7 mg/1 and 15.6 mg/1. The plant association along the banks is the hornbeam (Carpinus betulus L.). 116 O. Kiss: The Trichoptera (Insecta) of the Csorgo Brook in the Matra Mountains (North Hungary) Fig. 1: Map of the study area ©Slovenian Entomological Society, download unter www.biologiezentrum.at Acta entomologica slovenica, 12 (2), 2004 Csórgó brook, below the confluence of the three brooks, Cs2 sampling site. It is 800 m away from Nt sampling site, at 600 m a.s.l., where the water output is increased due to the inflow of the Hutahelyi brook from the NE and of the Gedeon brook from the SE. The maximum depth of water is 30 cm in the 'pot-holes', the width of the brook is 4-5 m. Water temperatures are similar to those at Nt sampling site. The air temperature ranges between 9.1°C and 17.7°C with the lowest value in September, and the highest in August. Conductivity changes from 245-287 pS/cm. Its pH range is 7.7-7.9, which is different from that of Nt sampling site. The oxygen content fluctuates between 6.35 mg/1 and 12.9 mg/1. Its accompanying vegetation comprises the common alder (Alnus glutinosa L. Gartn.) and hornbeam (Carpinus betulus L.), and at a distance from the brook, the beech (Fagus silvatica L.). Csórgó brook near the ruins of the watermill, Cs3 sampling site, 500 m from Cs2 sampling site at 580 m a.s.l. Here, the brook has a main branch of 4 m in width with an average of 20 cm in depth and two branches of about 30-40 cm in width and 5-10 cm in depth each. The bottom is covered with rocks of medium size. In some higher places alder trees are found near the brook. Water temperature ranges between 9.8 and 17.8°C with minimum and maximum values in September and August, resp. The conductivity is lower, 223-268 pS/cm, its pH is 7.6 or 7.7, the oxygen content ranges between 6.6 mg/1 and 12.73 mg/1. Here, the accompanying vegetation also comprises the common alder (Alnus glutinosa L. Gartn.) and the hornbeam (Carpinus betulus L.). Tab. 1: The Trichoptera of the Csorgo brook, Matra Mts. Hungary (A= total number of individuals, B= larva, C= cocoon, D= imagine, E= empty case) Species A B C D E RHYACOPHILIDAE 1 Rhyacophila fasciata (H., 1859.) 6 5 1 2 Rhyacophila oblitérala (McL., 1863.) 7 4 3 3 Rhyacophila tristis (P., 1834.) 10 6 2 2 GLOSSOSOMATIDAE 4 Agapetus sp. (indet.) 14 14 5 Synagapetus sp. (indet.) 2 2 PHILOPOTAMIDAE 6 Philopotamus montanus (D., 1813.) 51 31 10 10 HYDROPSYCHIDAE 7 Hydropsyche angustipennis (C., 1834.) 17 8 Hydropsyche exocellata (D., 1841.) 8 8 9 Hydropsyche fulvipes (C., 1834.) 9 9 10 Hydropsyche instabilis (C., 1834.) 28 26 1 1 11 Hydropsyche pellucidula (C., 1834.) 1 1 12 Hydropsyche sp. (indet.) 23 18 4 1 POLYCENTROPODIDAE 13 Plectrocnemia conspersa (C., 1834.) 25 22 3 118 O. Kiss: The Trichoptera (Insecta) of the Csörgö Brook in the Mätra Mountains (North Hungary) 14 Polycentropus flavomaculatus (F., 1834.)_1 1 PSYCHOMYIDAE 15 Tinodes rostocki (McL., 1878.) 4 3 1 LIMNEPHILIDAE 16 Ecclisopteryx madida (McL., 1867.) 41 24 1 16 17 Grammotaulius nigropunctatus (R., 1783.) 1 1 18 Halesus digitatus (S., 1781.) 78 78 19 Limnephilus sp. (indet.) 2 2 20 Potamophylax latipennis (C., 1834.) 24 21 3 21 Stenophylax permistus (McL., 1895.) 2 2 SERICOSTOMATIDAE 22 Notidobia ciliaris (L., 1761.) 2 1 1 23 Sericostoma personatum (K. et S., 1826) 22 13 9 ODONTOCERIDAE 24 Odontocerum albicorne (S., 1763.) 7 2 7 TOTAL: 377 294 30 16 37 Csorgo brook, 300 m downstream from the previous sampling site, Cs4 sampling site, at 560 m a.s.l. Here, the brook has a main branch of 4 m in width with an average of 25 cm in depth and one branch of 1.5 m in width and 15-20 cm in depth. The bottom is covered with small stones. Water current speed is lower because of the less steep slope. Water temperature ranges between 9.3 °C and 17.8 °C. The conductivity varies between 222 ¡aS/cm and 267 pS/cm, which are almost identical with the values for the previous sampling site. The water pH is 7.7 or 7.8, the oxygen content varies between 6.2 mg/1 and 12.41 mg/1. Its plant association comprises the common alder (Alnus glutinosa L. Gartn.) and the hornbeam (Carpinus betulus L.). Csorgo brook, 300 m downstream from the previous sampling site, Cs5 sampling site, at 540 m a.s.l. The brook flows in a narrow valley and has only one branch of 5 m in width and 20-30 cm in depth. The bottom is covered with small stones and gravel. Water temperature is slightly higher than at the previous site; it ranges between 9.7°C and 18.2°C as minimum and maximum, resp. The water pH is 7.8, the oxygen content of water varies from 6.1-12.4 mg/1. On the banks the hornbeam (Carpinus betulus L.) is found, but the common alder (Alnus glutinosa L. Gartn.) is not present. In general, the presence of large amounts of disintegrating material of plant origin, i.e. detritus is typical of the sampling sites. The water temperature measured monthly at the sampling sites is almost constant. The warmest month is August (23.8 °C) the coolest one is September (13 °C). Conductivity is lower at N, sampling site than at the others as it is beyond the confluence of the three brooks (Narád, Hutahelyi, and Gedeon). The water pH slightly varies (7.6-7.9), the water is slightly alkaline. The oxygen content in May is 136 %, in June and July it is 50 % and in September there is an increase in it, it is 85%. The oxygen content of the water shows wide ranges but also identical values at the different sampling sites, and largely depends on the quantity and time of precip- 119 ©Slovenian Entomological Society, download unter www.biologiezentrum.at Acta entomologica slovenica, 12 (2), 2004 Fig. 2: Cluster analysis of the sampling sites along the Csorgo brook (NuCoS A 1.05) itation prior to the measurement, on the water current speed and also on the smaller rapids and water falls. Sunlight only reaches the brook in small spots because of the shade by the deciduous trees along the brook. Discussion The total number of trichopteran species collected from the Narad and Csorgo brooks is 24 (Table 1.). 120 O. Kiss: The Trichoptera (Insecta) of the Csörgö Brook in the Mätra Mountains (North Hungary) Nj sampling site: 14 species of Trichoptera were collected and the following species occurred in large numbers: Halesus digitatus (9 inds/m2), Ecclisopteryx madida (7 inds/m2), and Hydropsyche instabilis (5 inds/m2). The number of individ-uals/m2 for the net-spinning Hydropsyche fulvipes, Hydropsyche sp. and Plectrocnemia conspersa varied from 1-5 inds/m2. Small numbers of individuals of Sericostoma personatum (2 inds/m2) were collected. Cs2 sampling site: A total of 17 species was collected here. The larvae of Agapetus sp., Halesus digitatus and Ecclisopteryx madida were collected in large numbers (8,8, and 5 inds/m2, resp.). Sericostoma personatum, Halesus digitatus and Plectrocnemia conspersa occurred in all four months. Notidobia ciliaris and Tinodes rostocki are to be considered rare species. Cs3 sampling site: 13 species were collected, with Philopotamus montanus as the most abundant species (11 inds/m2). Halesus digitatus and Hydropsyche exocellata also occurred in large numbers (7 inds/m2 and 5 inds/m2, resp.). Plectrocnemia conspersa was collected each month. Rhyacophila tristis is a subalpine species. Cs4 sampling site: 14 species were collected. Halesus digitatus, Philopotamus montanus and Potamophylax latipennis were found in large numbers (9, 7, and 5 inds/m2 resp.). Halesus digitatus was collected in all four months. Hydropsyche angustipennis, H. exocellata, H. fulvipes, H. instabilis, and Hydropsyche sp. occurred in small numbers (1 ind/m2). Cs5 sampling site: Also 14 species were collected. Halesus digitatus and Potamophylax latipennis were collected in large numbers (23 and 5 inds/m2, resp.), the latter one was found each month. From among the net-spinning species the number of individuals for Hydropsyche fulvipes, H. instabilis, H. sp., Philopotamus montanus and Plectrocnemia conspersa varied between 1 ind/m2 and 3 inds/m2. Acknowledgements This study was financially supported by the Hungarian National Science Fund (OTKA, Grant No T: 026479) and the Foundation for Hungarian Higher Education and Research (AMFK Grant No 310/98), and the Liceum Pro Scientiis Fund, Eger. References Hickin, N. E., 1967: Caddis larvae of the British Trichoptera. Hutchinson of London. 1-453. Kamler, A., Riedel, W., 1960: Method for Quantitative Study of the Bottom Fauna of Tatra Streams. Polsch. Hydrol. 8, 95-105. Kiss, O., 1977, 1999: Trichoptera ökolögiai vizsgälatok jellegzetes Bükk hegysegi forräs-es patakvizekben (Szalajka, Disznösküt, Sebesviz). Doctoral and PhD thesis, Debrecen, KLTE, kezirat, 1-235. 121 ©Slovenian Entomological Society, download unter www.biologiezentrum.at Acta entomologica slovenica, 12 (1), 2004 Kiss, O., 1980: Adatok a Mätra es a Bükk tegzeseiröl (Trichoptera). Data on the Trichoptera of the Mätra and Bükk Mts., Folia Ent. Hung. 33. 369-370. Kiss, O., 1981: Trichoptera in the Ilona Stream of the Mätra Mountains, North Hungary. Proc. of the 3rd Int. Symp. on Trichoptera, ed. by G.P. Moretti, Series Entomologica, Vol. 20. Dr. W. Junk Publishers, The Hague. 129-138. Macan, T., 1958: Methods of Sampling the Bottom Fauna in Stony Streams. Int. Assoc. of Theoretical and Applied Limnology. Comm. 8. Malicky, H., 1983: Atlas of European Trichoptera. Dr. W. Junk Publishers, The Hague-Boston-London. 1-297. Oläh, J., 1965: Trichoptera tanulmänyok. Szakdolgozat. Kezirat. KLTE, Debrecen, Zool. Inst. Schmera, D., Kiss O., 2000: Mintavetelezesböl adödö elteresek tegzesek (Trichoptera) vizsgälata eseteben. Hidrolögiai Közlöny. 80. evf. 5-6. 383-384. Ujhelyi, S., 1974: Adatok a Bükk es a Mätra-hegyseg tegzesfaunäjähoz. Fol. Hist.- nat. Mus. Matr. Gyöngyös. 2. 99-115. Waringer, J., Graf, W., 1997: Atlas der österreichischen Köcherfliegenlarven. Wien, Facultas-Univ.-Verl. 1-286. 122