Understanding the impact of urbanization on spider (Arachnida, Araneae) diversity in Armenia

Abstract

The effect of urbanization on biodiversity has become a prominent area of ​​investigation, highlighting the need for extensive research in this field. This study focuses on assessing the variation in spider diversity across an urban landscape (Urban area with gardens, urban without gardens and urban gardens). Our survey took place in Yerevan City and suburbs with increasing urbanization, where we aimed to elucidate the diversity of spider species along transects extending from the city center to Jrvej suburban area. Through a combination of observational data and sample collection, we observed a noticeable pattern: The total species richness was 111 species belonging to 72 genera and 21 families. The family Theridiidae had the highest diversity (17 species). The total occurrence of spiders was 276, with the highest occurrence in the urban zone with a garden (187 specimens). The most abundant species were: Pholcus phalangioides (Fuesslin, 1775) (33 specimens) (Pholcidae), Steatoda paykulliana Walckenaer, 1805 (20 specimens) (Theridiidae), and Oecobius nadiae (Spassky, 1936) (Oecobidae) (8). The highest diversity of spiders was found in the urban zone with a garden (buildings with a garden) (85 species). In the course of our study, we identified 36 spider species that are new to Armenian Araneofauna. These findings contribute to the expanding body of knowledge indicating the importance of vegetation cover in urban areas to preserve biodiversity amid urbanization pressures, based on the spider diversity in pure building and green areas was less than the mixed habitat in urban environments.