Size-age differences in the bioecology of Mesobuthus eupeus (C.L. Koch, 1839) (Arachnida, Scorpiones, Buthidae) in Azerbaijan

The biotopical distribution, size and age structure of the population, nocturnal activity rhythm and feeding of the mottled scorpion (Mesobuthus eupeus) were studied. The research was conducted on the left bank of the Pirsagat river (Shirvan plain, Istern Azerbaijan). All discovered individuals of scorpions were divided into 5 size and age groups by the length of the metasome. The biotopical distribution of the mottled scorpion had a pronounced aggregated character with the formation of local clusters (settlements) in which 5 types of ratios of size and age groups were identified. It was found that individuals of II groups and I have unimodal, III and IV groups - bimodal, and V group - trimodal character of the rhythm of nocturnal activity. As the size of scorpions increases, the breadth of the nutrition spectrum increases, and the intensity of nutrition decreases. The index of electivity in II groups and I had negative values, and from III to V groups for some taxa of preys - positive values. Representatives of the orders Isopoda (Crustacea), Aranei (Arachnida), Hymenoptera and Lepidoptera (Insecta) play a leading role in the nutrition of individuals of all size- age groups. As the size of scorpions increases, the proportion of members of the orders Hymenoptera, Blattodea and Collembola in their diet decreases. Representatives of the orders Coleoptera and Orthoptera are noted in the diet of scorpions from group III to V groups. Representatives of the orders Pulmonata (Gastropoda), Lumbricidae (Oligochaeta), Scolopendromorpha (Chilopoda), and Solifugae (Arachnida) are present in the diet only in individuals of IV and V groups.