A check list of the spiders of the Kruger National Park , South Africa ( Arachnida : Araneae )

As part of the South African National Survey of Arachnida (SANSA), projects are underway to determine the biodiversity of arachnids present in protected areas in South Africa. Spiders have been collected over a period of 16 years from the Kruger National Park, South Africa. A check list is provided consisting of 152 species, 116 genera and 40 families. This represents about 7.6 % of the total known South African spider fauna. Of the 152 species, 103 are new records for the park. The ground dwelling spiders comprise 58 species from 25 families. Of these, 21 % are web dwellers and 62 % free living, while 17 % live in burrows. From the plant layer, 94 species have been collected of which 53 % were web builders and 47 % free living wandering spiders.


Introduction
Conservation biologists are starting to recognise the importance of the invertebrate component in the functioning of healthy ecosystems.Therefore, any approach to conservation needs to take into account the composition of these invertebrate fauna.Inventories, with resulting check lists, provide valuable baseline information on species present and are the first step toward a better understanding of the fauna of the area.
In 1997, the South African National Survey of Arachnida (SANSA) was initiated (Dippenaar-Schoeman & Craemer 2000) with its main aim to make an inventory of the arachnid diversity of South Africa.One of the projects of SANSA is to compile an inventory of spiders presently conserved in parks and reserves in South Africa.
Although spiders constitute an abundant and highly diverse group of invertebrate animals, little is still known about their diversity even in conserved areas.From South Africa check lists exist for the spider fauna of the Moun-tain Zebra National (Dippenaar-Schoeman 1988), Roodeplaat Dam Nature Reserve (Dippenaar-Schoeman et al. 1989), Karoo National Park (Dippenaar-Schoeman et al. 1999), Makelali Nature Reserve in the Limpopo Province (Whitmore et al. 2001) and the Western Soutpansberg (Foord 2002).
The aim of this study was to compile the first check list of the spider species of the Kruger National Park (KNP) and to determine the percentage of species protected.This was not an intensive survey but reflects on collecting done in the park over a period of 16 years.Although this survey may not reflect the true diversity and species richness of the area, it does give an indication of species present.

Study area
The Kruger National Park (KNP) is situated in the Lowveld region of the Mpumalanga and Limpopo Provinces of South Africa.The park is 350 km long from north to south with a surface area of 1 948 528 ha.The climate is subtropical, with the annual rainfall varying between 700 mm in the south and 400 mm in the north.It falls within the Savanna Biome and the vegetation includes mixed bushwillow woodlands, mountain bushveld, thorn thicket, thorn veld, sourveld, scrubveld, sandveld and riverine forest.

Collecting methods
Sporadic collecting was mainly undertaken from 1985 to 2001.Spiders were sampled by hand (ground and plant search, turning rocks and sifting of leaf litter) or using a sweepnet or beating tray for grass and low shrubs.The new records were identified by the first author and are housed in the National Collection of Arachnida (NCA) at the ARC-Plant Protection Research Institute in Pretoria.The lack of taxonomic research in southern Africa within certain families made the identification of some genera to species level impossible.In some families, only immature specimens were collected, hampering identification to species level.This means that, in both instances, only generic names are included in the check list.

Guilds
A guild is a group of species that potentially compete for jointly exploited limited resources (Polis & McCormick 1986).Because most spiders live in a defined environment with limitations set by both physical conditions and biological factors (Foelix 1982), species can be grouped into guilds based on available information on their habitat preferences and predatory methods.For the present study two main guilds were recognised, namely wandering spiders (W) and web builders (WB), with further subdivisions based on micro-habitat and general behaviour (Table 1).

Numbers present
Forty families represented by 116 genera and 152 species are presently known from the KNP (Table 2).Of the 152 species listed 103 are new records for the KNP (Table 2 & 3 Schoeman, 1994 (Philodromidae) and Pseudomicrommata longipes Bösenberg & Lenz, 1895 (Sparassidae), while others with their green or straw-coloured bodies blend in with the grass, e.g., members of the families Oxyopidae and Thomisidae.

Conclusion
Preliminary investigations into the biodiversity of invertebrate fauna in South Africa have highlighted the lack of baseline information on the ecology and diversity of most arachnid groups (Dippenaar-Schoeman 2002b).This survey of the KNP forms part of the South African National Survey of Arachnida (SANSA) and data gathered will be used in the Savanna Biome Project, Mpumalanga Biobase Programme and Arachnida in Conserved Area Projects.
Of the 2000 spiders presently known from South Africa (Dippenaar-Schoeman 2002b), the 152 species of KNP represent about 7.6 % of the total spider fauna, with 103 species being new distribution records.Although this paper reports on sporadic collecting and probably represents only a portion of the spider fauna present, we hope this information will stimulate further research on this group of animals in the KNP.Future projects for the park include a key to the spiders and maps showing their distribution patterns.
The species list includes published

Table 2
Spider families collected at the Kruger National Park indicating the number of species and genera in each family and the number of species that are new records (NR) Members of the genera Argiope, Afracantha and Gasteracantha of the Araneidae and Leucauge, Nephila, Nephilengys and Tetragnatha of the Tetragnathidae construct large orb-webs between plants and are seen in their webs during the day.The tropical tent-web spider Cyrtophora citricola (Forskål, 1775) makes horizontal adapted orb-webs in plants like aloes.Most of the other orb-web species are nocturnal, e.g., the bark spider Caerostris, and remove their webs early each morning.The retreat webs of the Dictynidae, Eresidae and Segestriidae are made on different parts of the plants.Two species of the genus Stegodyphus, S. dumicola Pocock, 1898 and S. parts of the plant.The KNP, as part of the Savanna Biome, is represented by about 32 grass-living species.Many of the grass dwellers are well camouflaged with elongated bodies, e.g., Runcinia spp.(Thomisidae), Tibellus sunetae Van den Berg & Dippenaar- * from unpublished MSc and PhD theses.BGW = burrow ground dwellers; FWB = funnel web; FGW = free living ground wanderer; FPW = free living plant wanderers; GWB = gumfoot-web; OWB = orb-web; NR = new collecting record; SHWB = sheetweb; SPWB = space web.other