Rove beetle (Coleoptera: Staphylinidae) communities of the upper forest line of the Ukrainian Carpathians: structure and biotopic distribution (on the example of the Polonynskyi ridge)

The results of studies of species diversity, community structure, and biotopic distribution of rove beetles (Insecta: Coleoptera: Staphylinidae) at the upper forest line on the Yavirnyk and Stinka mountain ridges (Polonynskyi massif, Ukrainian Carpathians) are presented. As a result, 91 species of Staphylinidae belonging to 53 genera and 10 subfamilies were found. In particular, 71 species were found on Yavirnyk, and 69 species on Stinka. The largest number of species was noticed on meadows of both ridges: 48 species on Yavirnyk and 51 on Stinka. The lowest number of species was recorded in in ecotones: 39 species on Yavirnyk and 40 on Stinka. The rove beetle dominant complex of the Yavirnyk ridge includes four species, including two eudominants—Eusphalerum alpinum and Philonthus politus, and two dominants—Eusphalerum anale and Philonthus decorus. The dominant complex of the Stinka ridge includes six species: three eudominants—Eusphalerum alpinum, Ocypus macrocephalus, and Staphylinus erythroptery, and three dominants in almost equal proportions—Anotylus mutator, Dinothenarus fossor, and Philonthus decorus. All indices of species richness and diversity of the rove beetle communities have higher values on the Stinka ridge, and they are the highest in forest biotopes of both mountain ridges, which indicates their high ecological quality and stability. This is also confirmed by the highest rate of originality of the species composition of Staphylinidae in these areas. The most similar in species composition are the rove beetle communities of meadows. The original fauna of rove beetles of Yavirnyk is represented by 25 species, and of Stinka by 19 species. Among the species of Staphylinidae, 18 occurred in all biotopes of the upper forest line, which is 19.8% of the total number of species found here. In terms of trophic specialization, predators that live in the forest floor, among remains of organic origin and in fungi predominate in all biotopes of the upper forest line (UFL). In terms of biotopic distribution, eurytopic species predominate.