Species composition and abundance of the spider fauna of the Hillside Dams Conservancy, Bulawayo. Zimbabwe

Abstract

The objective of the study was to describe the spider species composition and abundance of a semi arid protected area in Zimbabwe, the Hillside Dams Conservancy. The paper aims to introduce a neglected group of invertebrates –the arachnids which is primarily unknown to science particularly in Zimbabwe. Spiders were collected in ten weekly sessions from last week of July to September 2012, using sweep nets and beating trays. A total of 663 individuals belonging to 28 species distributed among 11 families were found in the conservancy. The Oxyopidae was the most abundant (n = 230) representing 35% of all spiders sampled, followed by Philodromidae (n = 140) with 21%, Thomisidae (n = 124) with 19%, and Salticidae (n = 87) with 13%. The most abundant species was an Oxyopidae Oxyopes sp (n = 186) representing 28% of the total, followed by a Philodromidae Philodromus sp (n = 120) with 18.1%, a Salticidae Salticidae sp (n = 82) with 12.4%. The Thomisidae was the most species rich family with twelve species, followed by Philodromidae with four species and the Oxyopidae with three species. Observed spiders belonged to five functional groups: stalkers, foliage wanderers, ambushers, orb weavers and ground wanderers in the ratio of 3: 3: 6:2:1 with regards to species richness. Spider diversity in protected areas in Zimbabwe is not yet well known despite their usefulness as indicators of the overall species richness and status of ecosystems, therefore this study sought to fill the existing void of Arachnology literature for the state and apprise future investigators of the spider fauna of Zimbabwe.