O. Merkl szerk.: Folia Entomologica Hungarica 68. (Budapest, 2007)

FOLIA ENTOMOLOGICA HUNGARICA ROVARTANI KÖZLEMÉNYEK Volume 68 2007 pp. 123-135. A study of the cow pat Diptera on the Hortobágy, Hungary L. PAPP Department of Zoology, Hungarian Natural History Museum and Animal Ecology Research Group of the Hungarian Academy of Sciences H-1088 Budapest, Baross u. 13, Hungary. E-mail: lpapp@nhmus.hu Abstract - Applying a novel way of sample collection and a quick method of identification, cow pat Diptera of the Hortobágy National Park (at Nagyiván, Hungary) were sampled in 2003 to 2005. In 1015 samples of standardised sample collection 92680 individuals of 106 species were found and determined, of them 75 species were represented by less than 0.1% relative abundance. The dominance of Coproica luguhris (HALIDAY, 1836) was most characteristic, independently to the dry or wetter periods. Three species new to Hungary and ten species new to the Hortobágy National Park are reported. With 2 figures and one table. Key words - Ecology, Diptera, cow pats, sampling methods, identifications, Hortobágy, Hungary. INTRODUCTION Generally accepted in the literature, that proper samples of insect and other animal collections (whose individual numbers are high enough), reflecting the structure of real multispecies populations sampled, show characteristic distribution of species frequencies or species abundance. It is important to make distinction of the former term to the number, or, frequency of species, which may mean also the number of species in given abundance classes. As for "structure", in our case we have to mean a kind of abundance structure (represented e.g. by a frequency vector). We do not need to presume direct relationships (trade-offs) between species populations, or these kinds of relationships are negligible. This is a result of the fact that larval populations do not compete for food; foodstuffs are available in multiply quantity of requirement (see PAPP 1971, etc.). Further on, the predator populations prey upon not only