Spiders and Carabid beetles as the elements of arthropod’s diversity in ecosystems of Lva-Stvyga inter-river area (Rivne province, Ukraine)

Abstract

The series of epigeibiontic Arthropoda communities are investigated in several fo­rest and woodland ecosystems of Lva-Stvyga inter-river area within Volyn Polissia region of Ukraine. This is remoted district with peculiar ecological features as well as dominancy of oligotrophic forest and peat-bog ecosystems. The material of epigeibiontic arthropods was collected in spring and summer 2015 by the method of Barber’s pitfall traps. There are three pilot areas explored: 1) wet oligotrophic pine woodland (Ledo-Pinion); 2) late secondary succession of wet oligotrophic pine woodland cutting area; 3) dry oligotrophic pine woodland on the sands (Dicrano-Pinion). In total, 186 species of epigeibiontic arthropods were explored. There were found 75 species of spiders (Araneae) and 27 species of ground beetles (Coleoptera, Carabidae) among them. Along with that, the ants (Formicidae) have dominancy within related communities with an amount about 82–87 % of total arthropod individual’s number, and Araneae both with Carabidae exceed 6–7 % of this number. Nevertheless, there are nine spider species found for the first time for Ukrainian Polissia region and 1 species – Gnaphosa nigerrima – for the territory of Ukraine. One Carabid beetle species (Cymindis vaporariorum) was found at the first time for West Polissia region of Ukraine. There is also a number of rare and less known Araneae and Carabidae species found. Thus, the species composition and structure of explored Araneae & Carabidae communities show many specific features, which are caused by characteristic ecological and biogeographical peculiarities of oligotrophic ecosystems within investigated area. Following research of related taxonomical groups has to be directed to the wider spectrum of ecosystems covering, especially to peat-bog and mire complexes as unique protected habitats in Ukraine and the European Union.