New data about ptyctimous mites (Acari, Oribatida) in Polish palm houses

In samples collected in 2012 at the palm house in Poznań, 5 species of ptyctimous mites were found; 3 of them were native species (Mesotritia nuda, Euphthiracarus cribrarius, Acrotritia ardua) and 2 were exotic species, pantropical Microtritia tropica and neotropical Phthiracarus phoxos. In the samples from the palm house in Łódź, 3 species were found; 2 of them were known from the palm house in Poznań (Acrotritia ardua and Phthiracarus ferrugineus), and the third has not been reported from Poland before: the very rare species Mesoplophora michaeliana, known so far from the southern part of the Western Palearctic. Some juvenile stages of Mesoplophora (M.) michaeliana and Mesotritia nuda are also described.