NEW DATA ON EARTHWORMS (OLIGOCHAETA: LUMBRICIDAE) OF THE REPUBLIC OF NORTH OSSETIA-ALANIA (CENTRAL PART OF THE NORTH CAUCASUS)

Abstract

Aim of this research: inventory of fauna, study of ecology, biotopic and altitudinal distribution of earthworm species in North Ossetia-Alania. Material and methods. The material was collected in 2017–2019 during the vegetation period of plants at altitudes of 221–2483 m above sea level. To account for earthworms within the biogeocenosis, soil samples measuring 25×25 cm2 were taken in 4–8 replicates to the depth of occurrence of soil invertebrates and traces of their vital activity. Earthworms were identified in accordance with modern views on the systematics of earthworms. Results and discussion. It is shown that at least 19 species of earthworms live in the Republic of North Ossetia-Alania; Aporrectodea caliginosa is listed for the first time for the region. For the first time, the altitudinal distribution of taxa has been studied, and ideas about the upper and lower limits of species distribution in the central part of the North Caucasus have been significantly expanded. It is shown that the chorological structure of the fauna is formed mainly by cosmopolitan species. All morpho-ecological groups of earthworms are noted; soil species themselves predominate. Conclusion. The presence of belts of broad-leaved forests and forest-steppe forms the overall species richness and diversity of morpho-ecological forms of earthworms. The dominance of Lumbricidae, belonging to the soil morpho-ecological group itself, is due to the influence of the semi-desert zone, which lies at the base of the altitudinal spectrum of the East-North Caucasian type of zonality. The mosaic nature of the mountainous terrain and warm climate allow species to penetrate beyond the boundaries of the ecological preference.

Keywords

• еarthworms
• altitudinal and geographical distribution
• ecology
• republic of north ossetia-alania
• central part of the north caucasus