Kabíček J. (2008): Cohabitation and intraleaf distribution of phytoseiid mites (Acari: Phytoseiidae) on leaves of Corylus avellana. Plant Protect. Sci., 44: 32-36.Leaves from uncultivated and unsprayed hazelnut shrubs, Corylus avellana, were sampled from June to August 2005 to obtain information on the phytoseiid mite taxocenoses, population density and intraleaf distribution. Six phytoseiid mite species were identified, of which three, Kampimodromus aberrans, Euseius finlandicus and Neoseiulella tiliarum, were more abundant. The eudominant, slowly moving K. aberrans was found on all leaf samples. Phytoseiid population density averaged 3.16 mites per hazelnut leaf. While on most leaves only one phytoseiid species was found, on some there was cohabitation of two (rarely three) species. The three frequent species mostly inhabited the sheltered microhabitat at the veins of leaves of C. avellana.