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Spider species distribution in the Cape Floristic Kingdom (CFK) was compiled as part of the South African National Survey of Arachnida (SANSA), whose main aim was to create a relational database for the country's arachnid fauna. Data from the CFK was extracted from taxonomic and faunistic published papers, as well as unpublished faunistic survey data in national collections. A total of 11 500 records from 130 localities were recorded in the CFK until the end of 2023, representing 62 families, 334 genera and 960 species, with two further families (Synotaxidae and Theridiosomatidae) only known from undescribed species. This represents 42.4% of the total spider fauna of South Africa. For each species, the global and CFK distribution, as well as the level of endemicity and a conservation assessment using the IUCN Red List criteria, are provided. A total of 269 spp. (28.0%) are endemic to the CFK, 49 spp. (5.1%) are of special concern, and 229 spp. (23.9%) are Data Deficient. However, most of the species (682 spp., 71.0%) have a wide distribution with no known threats and are categorised as Least Concern. Salticidae is the most species-rich family (128 spp.), with 30 spp. endemic to the CFK, followed by the Gnaphosidae (107 spp.), Thomisidae (86 spp.) and Lycosidae (49 spp.), while six families are represented by a single species. The last decade has seen an exponential growth in the knowledge of spiders in South Africa, and there are certainly many more species that must still be discovered and described. [ABSTRACT FROM AUTHOR]

Many human activities have an impact on the fauna and flora of the South African Grassland Biome, including agriculture, fire and urbanisation. Disturbances in grassland habitats often result in Hyparrhenia hirta, a native pioneer grass species, establishing dense stands. Here the assemblage composition, species richness and abundance of spiders associated with H. hirta tussocks was investigated at three grassland sites (annually burnt, suburban local road traffic and undisturbed control) in the central Free State Province of South Africa during winter 2015 and 2016. Further, inter-annual differences during a period of intense drought were evaluated. An increase in spider species richness, abundance and different assemblage composition with increased tussock height and basal circumference was expected, and we predicted these effects would differ between land use types. Overall, Tibellus spp. immatures (Philodromidae) and Poachelas striatus Haddad & Lyle, 2008 (Trachelidae) were the most abundant spider species, while Philodromidae and Gnaphosidae were the most abundant spider families at all three sites during both years. The most species-rich families were Gnaphosidae, Salticidae and Thomisidae. Over the two-year sampling period there was a significant decline in overall spider abundance (58.09 %) and species richness (28.17 %), which could be explained by the cumulative effects of a severe drought experienced in central South Africa during 2015 and 2016. Species richness and assemblage composition were influenced by tussock basal circumference and disturbance effects, but not by tussock height. Several species were associated with the control site, while certain diversity metrics of the burnt and road verge sites were more stable, pointing to the importance of primary productivity in the former and water in the latter, for spider diversity. Trade-offs related to disturbance need to be carefully considered when developing management strategies for biodiversity. [ABSTRACT FROM AUTHOR]

The spider diversity found in the Savanna Biome are discussed. A total of 1207 species from 62 families are known from this Biome alone, of which 36% are endemic to the savanna. [ABSTRACT FROM AUTHOR]

Riparian zone vegetation plays an integral role in freshwater ecology, notably by buffering water temperatures, and in providing habitat for the adult stages of many aquatic species. We measured the contribution that riparian vegetation makes to temperature buffering, and how this affects the freshwater fauna, specifically using changes in abundances of baetid may flies for the Luvuvhu River catchment in South Africa. Water temperatures were compared for shaded versus un-shaded sites, and thermal stress between seasons was estimated using a cumulative probability model for the most widespread mayfly species, Dabulamanzia media. It is concluded that thermal stress due to losses in riparian shading could be detected using mayfly abundances in a regular monitoring programme., (Copyright © 2021 Elsevier Ltd. All rights reserved.)