This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). This article belongs to the Section Insect Ecology, Diversity and Conservation. The material was collected during odonatological studies financed by the Doctoral Study of the Faculty of Biology and Biotechnology of Maria Curie-Skłodowska University and the individual grant for young employees and PhD students of this faculty entitled "Dragonflies (Odonata) as indicators of the condition of calcareous fens", |