©Slovenian Entomological Society, download unter www.biologiezentrum.at LJUBLJANA, JUNE 2004 Vol. 12, No. 1: 123-128 XVII. sieec, Radenci, 2001 FUNCTIONAL FEEDING GROUPS OF TRICHOPTERA ALONG THE VOROSKČ VALLEY RILL, BUKK MTS., NORTH HUNGARY Otto KISS Karoly Eszterhazy College of Education, Department of Zoology, 3300 Eger, Leanyka u. 6., Hungary E-mail: kissotto@gemini.ektf.hu Abstract. - 36 species with a total number of 3709 individuals were categorized into functional groups and the portions of the various groups were expressed in percentages. Collectors-filterers and predators accounted for the largest portion of the collections (80.39 %), represented by two species, followed by predators with 5.9 % of the individuals from 6 species. Collectors-filterers and shredders-herbivores accounted for 3.28 % and 2.85 % of the total number of individuals represented by two and one species, resp. Shredders-detritivores composed 2.69 % of the collections and were represented by six species. Although shredders-detritivores and herbivores only accounted for 2.02 % of the collected individuals, they were represented by the largest number of species (11). Shredders-detritivores and predators, scrapers and shredders were poorly represented; 1.32 %, 0.91 %, and 0.1 %, respectively. Key words: Trichoptera, functional feeding groups, rill, Biikk Mts., North Hungary Izvleček SKUPINE PO NAČINU HRANJENJA MLADOLETNIC VZDOLŽ POTOČKA V DOLINI VOROSKO, POGORJE BUKK, SEVERNA MADŽARSKA 36 vrst s skupnim številom 3709 primerkov smo razvrstili v skupine in deleže skupin izrazili v odstotkih. Zbiralci-filtratorji in plenilci, zastopani z dvema vrstama, zavzemajo največji delež v zbirkah (80,39 %). Sledijo plenilci s 5,9 % primerkov, pripadajočih 6 vrstam. Zbiralci-filtratorji in drobilci-rastlinojedci so zastopani s po 3,28 % in 2,85 % od skupnega števila primerkov. Pripadajo dvema in eni vrsti. Drobilci-drobirojedci sestavljajo 2,69 % zbirk in so zastopani s 6 vrstami. Čeprav 123 Acta entomologica slovenica, 12 (1), 2004 predstavljajo drobilci-drobirojedci in rastlinojedci le 2,02 % zbranih primerkov, so zastopani z največjim številom vrst (11). Drobilci-drobirojedci in plenilci, strgalci in drobilci so slabo zastopani, s po 1,32 %, 0,91 % in 0,1 %. Ključne besede: Trichoptera, skupine po načinu hranjenja, potoček, pogorje Biikk, severna Madžarska Introduction Trichoptera were investigated along the Vorosko valley rill via larva investigation and light trapping in two years. The objective of this study is to identify the trophic relationships of the trichopteran species inhabiting the rill and determine the portions of the various functional groups, obu ning an overview of the source of nutritional resources. ^JMtf Vorosko spring ff-UooS Hazhelykut spring fj-8 ^^ ^ v6^500 light trap *rj2 Felsolarkany ft " i- i : 16 000 Fig. 1. Map of the study area Study Area The Vorosko valley rill is situated in the Blikk Mts. (Fig. 1.) at 320-460 m a.s.l. The water of the spring breaks its way onto the surface in the form of a well spring of about 1 m high where the clay shale appears from under the limestone. The rill has an intermittent upstream reach of about 2000 m with water flow in April and May and a downstream reach of about 6000 m with continuous water flow due to the inflow of a small spring (Hazhelykut spring), a rill (Kos valley rill), and seepage waters (Toldikut). The riparian vegetation consists of brittle willow (Salix fragilis L.), white vine (Clematis vitalba L.), and elderberry (Sambucus nigra L.). The rill bed is shady, of 40-50 cm in width and 6-20 cm in depth. The water temperature ranges between 8.8°C and 13.6°C from 124 O. Kiss: Functional feeding grou|BS^3ifMhBpteraalong the VoroskoWaMey ril 1, Biikk Mts., North Hungary April to October, i.e. in the larval development phase. The rill bed is covered with small and large limestones with accumulations of detritus and silt in the rapids and on the rill side. Material and Methods The data are taken from the investigations carried out in 1981 and 1982, when sample collecting and light trapping as well as observations and measurements were made monthly at 12 sampling sites from April - October. The larvae of Trichoptera were collected using the methods of Kamler and Riedel (1960) and Macan (1958). The trichopteran imagines were captured in a light trap (Kiss, 1984a,b) set up in the garden of a forester's lodge (Varro haz) at 250 m a.s.l. The thermal and chemical conditions were recorded. For the identification of larvae and imagines Hickin (1967) and Malicky (1973) were used, resp. The collected species of Trichoptera are listed in functional groups using the categories and guideline of Merritt and Cummins (1984) and Moog (1995). The portions of the different functional feeding groups (Table 1) for the Vorosko valley rill are expressed in percentages of the total number of individuals. shredders - detritivores and herbivores 2,02% scrapers shredders - detritivores and 0,91 % predators \ 1,32% shredders - detritivores 2,69% collectors - filterers 3, predators 5,9% shredders 0,1% shredders - herhivnres 2,85% collectors - filterers and predators Fig. 2. Diversity and abundance of functional feeding groups of Trichoptera along the Vorosko valley rill, Biikk Mts., North Hungary 125 ©Slovenian Entomological Society, download unter www.biologiezentrum.at Acta entomologica slovenica, 12 (2), 2004 Tab. 1. Functional feeding groups of Trichoptera along the Vorosko valley rill, Biikk Mts., North Hungary SPECIES FUNCTIONAL FEEDING GROUPS Limnephilidae 1 Anabolia furcata (B.,1857) shredders ■ - detritivores 2 Chaetopteryx fusca (B„ 1857) shredders • - detritivores 3 Ecclisopteryx madida (McL., 1867) shredders ■ - detritivores 4 Grammotaulius nigropunctatus (R., 1783) shredders 5 Grammotaulius nitidus (M., 1764) shredders 6 Halesus digitatus (S., 1781) shredders ■ - herbivores 7 Limnephilus affinis (C„ 1834) collectors - filterers 8 Limnephilus auricula (C., 1834) shredders ■ - detritivores and herbivores 9 Limnephilus extricatus (McL., 1865) shredders • - detritivores and herbivores 10 Limnephilus flavicornis (F., 1787) shredders ■ ■ detritivores and herbivores 11 Limnephilus griseus (L., 1758) shredders • - detritivores and herbivores 12 Limnephilus lunatus (C., 1834) shredders ■ - detritivores and herbivores 13 Limnephilus politus (McL., 1865) shredders ■ ■ detritivores and herbivores 14 Limnephilus rhombicus (L., 1758) shredders detritivores and herbivores 15 Limnephilus sparsus (C., 1834) shredders ■ ■ detritivores and herbivores 16 Limnephilus vittatus (F., 1798) shredders ■ ■ detritivores and herbivores 17 Micropterna nycterobia (McL., 1875) shredders ■ • detritivores and herbivores 18 Micropterna testacea (G., 1790) shredders ■ ■ detritivores and herbivores 19 Potamophylax nigricomis (P., 1834) shredders ■ ■ detritivores 20 Stenophylax permistus McL., 1895 shredders ■ ■ detritivores LEPTOCERIDAE 21 Mystacides longicornis (L., 1758) shredders ■ ■ detritivores 22 Oecetis notata (R., 1842) predators 23 Oecetis ochracea (C„ 1825) predators POLYCENTROPODIDAE 24 Neureclipsis bimaculata (L., 1758) collectors ■ - filterers 25 Plectrocnemia conspersa (C.,1834) predators ODONTOCERIDAE 26 Odontocerum albicorne (S., 1763) shredders - ■ detritivores and predators PHRYGANEIDAE 27 Phryganea grandis (L., 1758) shredders - ■ detritivores RHYACOPHILIDAE 28 Rhyacophila fasciata (H„ 1859) predators 29 Rhyacophila tristis (P., 1834) predators SERICOSTOMATEDAE 30 Sericostoma personatum (K. et S., 1826) shredders - ■ detritivores GOERIDAE 31 Silo nigricomis (P., 1834) scrapers 32 Silo pallipes (F., 1781) scrapers GLOSSOSOMATIDAE 33 Synagapetus moselyi U., 1938 scrapers HYDROPSYCHTOAE 34 Hydropsyche bulbifera McL., 1878 collestors - filterers and predators 35 Hydropsyche instabilis (C., 1834) collectors ■ ■ filterers and predators ECNOMIDAE 36 Ecnomus tenellus (R., 1842) predators 126 O. Kiss: Functional feeding groups of Trichoptera along the Vorosko valley rill, Biikk Mts., North Hungary Results In 1981 and 1982 the total number of individuals were 3709 of 36 species. Collectors-filterers and predators accounted for the largest portion (80.39 %) due to the huge numbers of individuals of Hydropsyche instabilis and represented by the above species and Hydropsyche bulbifera. Predators composed 5.9 % of the collections, and were represented by Rhyacophila fasciata, Rh. tristis, Plectrocnemia con-spersa, Oecetis notata, O. ochracea, and Ecnomus tenellus. They are followed by collectors-filterers (3.28 %), represented by Limnephilus affinis and Neureclipsis bimaculata. Shredders-herbivores accounted for 2.85 % and were only represented by one species: Halesus digitatus. Shredders-detritivores only composed 2.69 % of the collections but were represented by six species (Anabolia furcata, Chaetopteryx fusca, Ecclisopteryx madida, Mystacides longicornis, Phryganea grandis, Potamophylax nigricornis, Sericostoma personatum, and Stenophylax permistus). Shredders-detritivores and herbivores accounted for 2.02 % and were represented by the largest number of species, by eleven Limnephilus species. Shredders-detritivores and predators (1.32 %) were only represented by Odontocerum albicorne. Scrapers (0.91 %) were represented by Silo nigricornis, Silo pallipes and Synagapetus mose-lyi. Shredders accounted for 0.1 % from two species (Grammotaulius nigropuncta-tus and G. nitidus, Fig. 2.). This diversity of trophic relationships of Trichoptera shows the availability of diverse nutritional resources. It may be stated that together with the 36 caddisfly species collected in the Vorosko valley rill, the total number of trichopteran species increased to 113 in the Biikk Mts., and similarly to the data obtained for other study areas of the Biikk Mts., collectors-filterers and predators composed the largest portion of the collections. Acknowledgements This study was financially supported by the Hungarian National Science Fund (OTKA, Grant No T: 026479), 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. Kamler, A., W. Riedel, 1960: Method for quantitative study of the bottom fauna of Tatra streams. Polsch. Hydrol., 8: 95-105. Kiss, O., 1984a: Fenycsapdaval gyujtott Trichopterak a Biikk hegysegi Vorosko-vol-gybol (Trichoptera collected by light-trap from Vorosko valley in the Biikk Mountains). Acta Acad. Paed. Agriensis, Nova Series 17. 709-718. Kiss, O., 1984b: Trichoptera in an intermittent rill of the Biikk Mountains, North Hungary, pp. 191-195. - In Morse, J.C. (ed.): Proceedings, of the 4th International 127 ©Slovenian Entomological Society, download unter www.biologiezentrum.at Acta entomologica slovenica, 12 (1), 2004 Symposium on Trichoptera, Clemson, 1983, Dr. W. Junk Publishers, The Hague, XXII + 486. Macan, T., 1958: Methods of sampling the bottom fauna in stony streams. Int. Assoc. of Theoretical and Applied Limnology. Comm 8. Malicky, H., 1973: Atlas of European Trichoptera. Series Entomologica, Dr. W. Junk Publishers, The Hague - Boston - London, 1-298 pp. Merritt, R. W. & Cummins, K. W. 1984: An introduction to the aquatic insects of North America. Second edition. Kendall/Hunt Publishing Company, Dubuque, Iowa, 302-311. Moog, O., (ed.) 1995: Fauna Aquatica Austriaca. Bundesministerium für Land-und Forstwirtschaft, Wien. 128