This study investigates the influence of microhabitat on the presence of several species of fungivorous beetles in basidiocarps of Fomes fomentarius (L.) Kickx. All dead basidiocarps of F. fomentarius from fragments of forest in an agricultural landscape in Norway were sampled and dissected, and their content of Cis jacquemarti Mellié, 1848/C. alter (Silvferberg, 1991) (did not distinguish between individuals of these two species), C. bidentatus (Olivier, 1790), C. lineatocribratus Mellié, 1848, Ennearthron cornutum (Gyllenhal, 1827) (Ciidae) and Dorcatoma dresdensis Herbst, 1792 (Anobiidae) were identified. Multiple logistic regression models revealed that these species responded differently to the microhabitat variables. The incidence of these beetles was associated with the size (volume), position (height above ground) and moisture content of the basidiocarps. The analyses also indicated possible interspecific interactions between some of the beetles. The presence of some of the species mainly in basidiocarps at particular stages of degradation indicates a successional pattern of occurrence of these species. Together these results indicate that basidiocarps of F. fomentarius are a heterogeneous resource for fungivorous beetles. This has implications for conservation: To preserve the diversity of fungivores, sufficient dead wood has to be left in forests to assure an adequate supply of F. fomentarius basidiocarps of different quality.
Habitat use of Bolitophagus reticulatus (L.) (Coleoptera: Tenebrionidae), living in the basidiocarps of Fomes fomentarius (L.) Kickx, was investigated in three forest areas in south-eastern Norway: (1) a continuous, coniferous forest, (2) an agricultural area with mostly deciduous forest islands in a matrix of cultivated land and (3) a homogeneous, old deciduous forest stand. B. reticulatus was almost exclusively found inside dead basidiocarps. The size of the basidiocarp was the most important variable for predicting the probability of B. reticulatus presence in the basidiocarps from all three study areas. Drier basidiocarps had a higher probability of beetle presence than the wetter ones. Basidiocarps situated above the ground level had a higher probability of beetle presence than those close to or on the ground level. In the first study area, the presence of Cisidae was found to reduce the probability of B. reticulatus presence perhaps as a result of competition. The disappearance of beetles from previously inhabited basidiocarps seemed to be due to depletion of resources.