A monograph of the ptyctimous mites (Acari, Oribatida) of Poland, typical xylophagous soil mites, has been prepared on the basis of 22 654 individuals found in 869 samples. A detailed analysis of morphology of representatives of ptychoid groups has been provided.
The species occurring in Poland have been classified into two cohorts of Arthroptyctima and Euptyctima, two superfamilies Phthiracaroidea and Euphthiracaroidea, 5 families: Mesoplophoridae, Oribotritiidae, Euphthiracaridae, Phthiracaridae and Steganacaridae, and 12 genera. Diagnoses of higher taxa have been followed by a review of the species. At present the number of species known from Poland is 40. Compared to the previous studies, the number of species known from Poland was enriched by 20, including six species new to the science. Each species is illustrated and characteristics of morphology as well as metric data are provided; synonyms are listed under specific names. Keys for identification of the species and higher taxa are given.