PREDATION ON THE GRASSBUG SPECIES NOTOSTIRA-ELONGATA (HETEROPTERA, MIRIDAE) BY NABIDAE (HETEROPTERA) AND SELECTED NON-WEBBUILDING SPIDERS (ARANEAE)

A total of 438 specimens of Nabidae, 262 of Tibellus oblongus (Walcken aer 1802) (Araneae: Philodromidae), and 19 of Xysticus cristatus (Aran eae: Thomisidae) from an Elytrigia repens-grassland, near Steudnitz / Thuringia, were tested serologically for feeding on the grassbug speci es Notostira elongata, using the Ouchterlony micro-technique. Nabis br evis, Nabis pseudoferus and T oblongus have been proved to be predator s of N elongata in the field. The qualitative importance of N elongata as prey for N brevis was investigated using data of density-measureme nts and feeding experiments. The temporal distribution of positive ser ological tests and the feeding experiments suggest that predation in t he field was only on larvae and eggs of N elongata.