The fruiting bodies of bracket fungi are a specific microhabitat colonized by various invertebrates of which mites (Acari) are rarely studied, and if they are, the study is usually faunistic. The aim of the research was to determine whether the diversification of mite assemblages (Mesostigmata, Oribatida) inhabiting the fruiting bodies of Fomitopsis pinicola (Sw.) P. Karst. (Polyporales) are connected with the character of the forests and/or the degree of decay (DD) of the fruiting bodies. The research was conducted at Białowieża National Park (BNP), in forests close to natural ones and in Karkonosze National Park (KNP) which was affected by a large-scale forest dieback in the 1980s. Eighty fruiting bodies (40 at each study site) of F. pinicola belonging to four DD categories were collected. In total, 4,345 individuals of 120 mite species were recorded at BNP, and 13,912 individuals of 96 species were recorded at KNP. Analyses revealed that the sample dispersion at each study site was comparable, nevertheless the samples from each study site were clearly grouped into slightly overlapping sets which allow observation of the differences between them. In the less decayed fungi (DD 1 and 2) there were fewer mite species and individual mites than in the more decayed samples (DD 3 and 4). There were also significant differences between the fauna of the fungi in each particular DD: the fauna of DD 1 differed from all others, whereas the fauna of heavily decayed fungi (DD 3 and 4) was more comparable.

支架真菌的子实体是由各种无脊椎动物定殖的特定微生境，其中螨虫（Acari）很少被研究，如果是，则该研究通常是动物学的。该研究的目的是确定栖息在Fomitopsis pinicola (Sw.) P. Karst子实体中的螨类组合 (Mesostigmata, Oribatida) 是否多样化。(Polyporales) 与森林的特征和/或子实体的腐烂程度 (DD) 相关。该研究是在比亚沃维耶扎国家公园 (BNP)、靠近自然森林的森林以及在 1980 年代受到大规模森林枯死影响的卡科诺泽国家公园 (KNP) 进行的。F. pinicola 的80 个子实体（每个研究地点 40 个）收集了属于四个 DD 类别的数据。在 BNP 总共记录了 120 种螨类的 4,345 个体，在 KNP 记录了 96 种的 13,912 个体。分析表明，每个研究地点的样本分布是可比的，但来自每个研究地点的样本清楚地分为稍微重叠的组，以便观察它们之间的差异。在腐烂程度较低的真菌（DD 1 和 2）中，与腐烂程度较高的样本（DD 3 和 4）相比，螨种类和个体螨虫更少。每个特定 DD 的真菌动物群之间也存在显着差异：DD 1 的动物群与所有其他动物群不同，而严重腐烂的真菌（DD 3 和 4）的动物群更具可比性。