This art icle was downloaded by: [ ARC Cent ral Office] , [ Professor A.S. Dippenaar- Schoem an] On: 16 January 2013, At : 04: 25 Publisher: Taylor & Francis I nform a Lt d Regist ered in England and Wales Regist ered Num ber: 1072954 Regist ered office: Mort im er House, 37- 41 Mort im er St reet , London W1T 3JH, UK Transactions of the Royal Society of South Africa Publicat ion det ails, including inst ruct ions f or aut hors and subscript ion inf ormat ion: ht t p: / / www. t andf online. com/ loi/ t t rs20 Current knowledge of spiders in South African agroecosystems (Arachnida, Araneae) A. S. Dippenaar-Schoeman a b , A. M. Van den Berg a , C. R. Haddad c & R. Lyle a a ARC-Plant Prot ect ion Research Inst it ut e, Privat e Bag X134, Queenswood, Pret oria, 0121, Sout h Af rica b Depart ment of Zoology and Ent omology, Universit y of Pret oria, Pret oria, 001, Sout h Af rica c Depart ment of Zoology and Ent omology, Universit y of t he Free St at e, PO Box 339, Bloemf ont ein, 9300, Sout h Af rica Version of record f irst published: 16 Jan 2013. To cite this article: A. S. Dippenaar-Schoeman , A. M. Van den Berg , C. R. Haddad & R. Lyle (2013): Current knowledge of spiders in Sout h Af rican agroecosyst ems (Arachnida, Araneae), Transact ions of t he Royal Societ y of Sout h Af rica, DOI: 10. 1080/ 0035919X. 2012. 755136 To link to this article: ht t p: / / dx. doi. org/ 10. 1080/ 0035919X. 2012. 755136 PLEASE SCROLL DOWN FOR ARTI CLE Full t erm s and condit ions of use: ht t p: / / www.t andfonline.com / page/ t erm s- and- condit ions This art icle m ay be used for research, t eaching, and privat e st udy purposes. Any subst ant ial or syst em at ic reproduct ion, redist ribut ion, reselling, loan, sub- licensing, syst em at ic supply, or dist ribut ion in any form t o anyone is expressly forbidden. The publisher does not give any warrant y express or im plied or m ake any represent at ion t hat t he cont ent s will be com plet e or accurat e or up t o dat e. The accuracy of any inst ruct ions, form ulae, and drug doses should be independent ly verified wit h prim ary sources. The publisher shall not be liable for any loss, act ions, claim s, proceedings, dem and, or cost s or dam ages what soever or howsoever caused arising direct ly or indirect ly in connect ion wit h or arising out of t he use of t his m at erial. Transactions of the Royal Society of South Africa http://dx.doi.org/10.1080/0035919X.2012.755136 REVIEW Current knowledge of spiders in South African agroecosystems (Arachnida, Araneae) Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 A.S. Dippenaar-Schoeman1,2, A.M. Van den Berg1, C.R. Haddad3 & R. Lyle1 1 ARC-Plant Protection Research Institute, Private Bag X134, Queenswood, Pretoria, 0121 South Africa; 2Department of Zoology and Entomology, University of Pretoria, Pretoria 001, South Africa; 3Department of Zoology and Entomology, University of the Free State, PO Box 339, Bloemfontein, 9300 South Africa *Author for correspondence. e-mail: DippenaarA@arc.agric.za Spiders are one of the most abundant predator groups found in agroecosystems and they have special adaptations towards a predatory way of life. The aim of this paper is to review our present knowledge of spider diversity in different agroecosystems of South Africa, as well as their potential prey. This paper provides a measure of what has been achieved in research on spiders in South African agroecosystems, and identifies directions for future research. A checklist of spiders found in these systems is provided, based on published surveys and data from the South African National Survey of Arachnida (SANSA) database, with information on the guilds that they occupy. Thus far, 51 families with 238 genera and 413 species have been recorded from crops in South Africa. Five agrobiont species have been listed that might play an important role as natural control agents of pests: Ostearius melanopygius (O.P.- Cambridge, 1879) (Linyphiidae); Pardosa crassipalpis Purcell, 1903 (Lycosidae); Cheiracanthium furculatum Karsch, 1879 (Miturgidae); Heliophanus pistaciae Wesołowska, 2003 (Salticidae) and Misumenops rubrodecoratus Millot, 1941 (Thomisidae). Keywords: Agrobiont species, agroecosystems, guilds, SANSA, Salticidae, Thomisidae INTRODUCTION Signatories of the Convention of Biological Diversity (CBD) are obligated to develop a strategic plan for the conservation and sustainable use of their biodiversity. In 1997, the South African National Survey of Arachnida (SANSA) was launched in accordance with the country’s obligations to the CBD (Dippenaar-Schoeman et al., 2010). Through SANSA, essential information has been gathered to address issues concerning the conservation and sustainable use of the arachnid fauna in South Africa. SANSA is an umbrella project that was implemented at a national level together with researchers and institutions countrywide, with a common goal to document and unify information on South African arachnids. The role of spiders as possible natural control agents of insects and mites needs to be evaluated, specifically for use in pest control strategies in agroecosystems (Nyffeler & Benz, 1987; Greenstone, 1999). Their inclusion in biodiversity inventories is clearly desirable, as they represent approximately 2.8% of global animal biodiversity with c. 43 500 described species (Zhang, 2011; Platnick, 2012), all of which are functionally significant as predators of other invertebrates. As part of SANSA, baseline information on spiders in agroecosystems sampled since 1972 was collated to address their possible sustainable use. While considerable effort has been put into gathering baseline data through surveys in agroecosystems in South Africa, there is still considerable scope for further experimental work on the biological control potential of the dominant agrobiont spiders in each agroecosystem. While predacious mites and insects have received most of the ISSN 0035-919X Print / 2154-0098 Online # 2013 Royal Society of South Africa http://www.tandfonline.com/ttrs attention in South African biological control programmes, the role of spiders appears to have been largely ignored, despite their importance as generalist predators (Smith-Meyer, 1996). Reviews on the role of spiders in agroecosystems (Luczak, 1979; Riechert & Lockley, 1984; Nyffeler & Benz, 1987; Nyffeler et al., 1994a,b; Green, 1996; Riechert & Lawrence, 1997; Sunderland, 1999; Symondson et al., 2002; Maloney et al., 2003; Royauté & Buddle, 2012) indicate an increasing interest in, and recognition of, spiders as natural control agents of insects and mites in field crops and orchards. Spiders are one of the most ubiquitous predator groups in South African agroecosystems (Van den Berg & Dippenaar-Schoeman, 1991), and inventories have provided valuable baseline information on the abundant species occurring on various commercial crops, including orchards. These studies have also provided an indication of species that can be considered to be agrobionts, i.e. species that reach high levels of abundance in agroecosystems (Samu & Szinetár, 2002), and which are likely to play an important role in the control of pest species. Spiders have special adaptations towards a predatory way of life. Their distensible abdomens enable them to consume a large amount of prey within a relatively short period of time, while their rate of predation may increase greatly for short periods when food is locally abundant (Turnbull, 1965). They have an exceedingly high resistance to starvation, which enables them to survive and maintain normal reproduction during periods of low prey availability (Anderson, 1974). This is accomplished by an ability to decrease their metabolic rates and also foraging activity. Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 2 Transactions of the Royal Society of South Africa Spiders are present throughout the year (Dippenaar-Schoeman, 1979), and during their lifespan, which varies from nine months to 25 years, all instars feed actively as predators. Food consumption decreases only before and during ecdysis, although a general decrease in food consumption during the adult male stage is quite common (Haynes & Sisojevic, 1966). Spiders are usually polyphagous and feed on a variety of available prey. Predation is not limited to adult insects only but includes the egg and larval or nymphal stages as well (Nyffeler et al., 1990). Spiders are some of the first predators to colonize newly planted crops, and research has shown the importance of early season assemblages in limiting pest numbers while their densities are low (Van den Berg & Dippenaar-Schoeman, 1991; Maloney et al., 2003). Different species of spiders may be found in different microhabitats. A large group of wandering spiders live on the ground, either under stones or in burrows or cracks in the soil, and they feed mainly on ground-living insects and larvae hibernating in the soil. The plant-dwelling spiders are present on the stems, foliage, bark or flowers of plants and many of them are nocturnal hunters, actively moving around in search of prey. A number of web-building spiders spin their webs between the leaves and branches, under the bark and even over the leaf surfaces. They will prey on any flying or crawling insects that come into contact with the silk threads of their webs. As predators, spiders have a two-fold effect. Not only do they feed directly on their prey, but their presence also causes indirect mortality. For example, the presence of foraging spiders can disturb insect larvae, which then drop from the plant and die, or are exposed to predation by grounddwelling predators (Mansour et al., 1981). Further, the reduced time that phytophagous pests spend on plants following disturbance may reduce the damage that they cause to the crop plants (Riechert, 1999). The webs spun over the leaves also seem to make them less suitable for oviposition and feeding by pests (Van den Berg et al., 1992). Spiders have the added benefit of effecting wasteful or superfluous killing, where more prey are killed than are actually fed on, particularly at high prey densities. Thus, more prey are killed than are actually required by the spider, resulting in a greater degree of pest control (Sunderland, 1999). The aim of this paper is to review our present knowledge of spider biodiversity in different agroecosystems in South Africa, and the prey that spiders consume in crop systems. Any field of endeavour requires retrospection after a period of activity, which provides a measure of what has been achieved and identifies directions for future research. A checklist of spiders found in South African agroecosystems is provided, with information on the guilds that they occupy, and agrobiont species that might play a role as natural control agents are discussed. MATERIAL AND METHODS Surveys In South Africa, the first arachnid sampling in an agroecosystem was undertaken in 1972 to investigate the role that spiders play in strawberry fields in the biological control of spider mites (Dippenaar-Schoeman, 1976, 1979). This was followed by extensive surveys of spiders in conventionally cultivated cotton fields (Dippenaar-Schoeman et al., 1999; Van den Berg & Dippenaar-Schoeman, 1991; Van den Berg et al., 1990), as well as in fields of genetically modified Bt-cotton Vol. 00(00): 1
18, 2013 (Mellet, 2005; Mellet et al., 2006). A number of surveys in orchards in the Mpumalanga Lowveld resulted in papers on spiders on citrus (Dippenaar-Schoeman, 1998; Van den Berg et al., 1992), macadamia (Dippenaar-Schoeman et al., 2001a, b) and avocado (Dippenaar-Schoeman et al., 2005), while further surveys were conducted in pistachio orchards in the arid Northern Cape (Haddad, 2003). Records of spiders sampled in a variety of crops as part of unpublished studies are also included in the species list (Appendix 1). A considerable proportion of records have only been identified to genus level, but only those species identified to species level are included in the list. Genus level records are only included if no species in that genus have been identified to species level (Appendix 1). Database Data on spider species in agroecosystems in South Africa were obtained from existing datasets for this region compiled for the First Spider Atlas of South Africa (Dippenaar-Schoeman et al., 2010). Records were obtained from the primary data of specimens housed in the National Collection of Arachnida (NCA) at the ARC-Plant Protection Research Institute (ARCPPRI), Pretoria (50 000 records), as well as a digital photographic database containing images of species recorded on crops by the public. Guilds A guild is a group of species that potentially compete for jointly exploited limited resources (Polis & McCormick, 1986). For the present study, two main guilds were recognized, namely wandering spiders (W) and web-builders (WB), with further subdivisions based on their preferred microhabitat or type of web constructed (Foord et al., 2011) (Appendix 1). Web-building spiders construct webs to capture their prey. The majority of web-builders spin webs on the plants, either on, between or around leaves and flowers, between branches, or between trees, and usually catch flying insects. Several families (e.g. Linyphiidae and Agelenidae) construct webs close to the soil surface or in low-growing vegetation, such as orchard ground covers. Wandering spiders actively hunt their arthropod prey. Many wandering spiders are nocturnal and construct tubular retreats of silk in which they spend periods of inactivity during the day. Some families (e.g. Salticidae, Thomisidae and some Lycosidae) are diurnally active and rest at night, either in silk retreats or hanging from draglines from vegetation. Resting retreats are spun in many different microhabitats, including beneath young leaves, in curled or dead leaves, within inflorescences, under bark, in soft sand, or in grasses and weeds in the ground cover vegetation. Agrobiont species Agrobiont species are defined as species that reach a high degree of dominance in agroecosystems, that may usually only be found in high numbers in natural habitats that are frequently disturbed (Samu & Szinetár, 2002). Furthermore, they defined agrobionts as species with an average dominance of greater than 1% in arable fields that occurred in at least 75% of the fields sampled within a particular geographical region, in that case Hungarian cereal fields. Particular agrobiont species are usually characteristic of agroecosystems of fairly similar structures, e.g. cereals and alfalfa (Samu et al., 2011). The agrobionts associated with arable lands, orchards and rice paddies, for example, are inherently different due to differences in the structure of the vegetation and the A.S. Dippenaar-Schoeman et al.: Knowledge of Spider Diversity in Agroecosystems contrasting management strategies applied in each (Samu & Szinetár, 2002). We regarded agrobiont species as those representing more than 1% of all the individuals in a sampled assemblage from a particular crop. It is also important to consider how widespread the occurrence of a species in the considered crop(s) is. Species that are below this limit, but still common in fields, are called ‘‘agrophile’’ species after Luczak (1979). RESULTS AND DISCUSSION Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 Crops Avocado South Africa is the world’s fourth-largest producer of avocado (Persea americana) (United States Department of Agriculture, 2005). Locally, avocado trees and fruit are attacked by at least 30 species of insects and mites (Van den Berg et al., 1999a). Spiders inhabiting avocado orchards in Israel were studied by Mansour et al. (1985), who assessed their role as natural enemies of the giant looper, Boarmia selenaria (Lepidoptera: Geometridae). In South Africa, surveys were carried out in two avocado orchards in the Mpumalanga Lowveld over a one-year period using canopy fogging as the collecting method (Dippenaar-Schoeman et al., 2005). A total of 3715 specimens representing 26 families, 68 genera and 90 species were collected. The Salticidae comprised 31.0% of the total spiders collected, followed by Thomisidae (23.9%) and Tetragnathidae (11.8%). The most species-rich families were the Araneidae (20 spp.), Salticidae (14 spp.) and Thomisidae (12 spp.). The thomisid Oxytate argenteooculata was the most abundant species and represented 22.2% of all spiders collected, followed by two salticids, Thyene coccineovittata (11.5%) and T. natali (11.0%), and a tetragnathid, Tetragnatha subsquamata (8.4%). Of the spiders collected, 77% were wanderers and 23% were web-builders. Citrus Large numbers of spiders are present in citrus orchards (Citrus spp.), as has been reported in South Africa (CatIing, 1970; Van den Berg et al., 1987), as well as in other countries (Shulov, 1938; Carroll, 1980; Mansour et al., 1982; Mansour & Whitcomb, 1986). Many of the pests and potential pests that occur on citrus in South Africa are under effective biological control (Bedford, 1978). However, the natural enemies of a few others, like the citrus psylla, Trioza erytreae (Hemiptera: Triozidae), are unable to keep these pests below the economic threshold. Several spider species have been observed to prey on citrus psylla (Van der Merwe, 1923; Catling & Annecke, 1968; Catling, 1970), and Van den Berg et al. (1987) expressed the opinion that spiders are possibly the most important predators of this pest. During a two year survey in Mpumalanga Province, South Africa, a total of 3054 spiders representing 21 families were sampled using beating and pittraps in an unsprayed citrus orchard (Van den Berg et al., 1992). Salticidae was the most abundant family (34.4%) followed by the Theridiidae (21.9%), Thomisidae (11.9%), Araneidae (7.9%) and Clubionidae (7.0%). Eighteen species of spiders were observed to prey on citrus psylla, while six species trapped nymphs and adults in their retreats or webs. The spider species most commonly found on the soil was Pardosa crassipalpis (Lycosidae), while the plant-dwellers are represented by Cheiracanthium furculatum (Miturgidae), Enoplognatha molesta (Theridiidae), 3 Eperigone fradeorum (Linyphiidae), and Misumenops rubrodecorata (Thomisidae). The wandering spiders constituted 61.5% of the spider fauna collected and the web-builders 38.5%. Data indicate that while spiders are unable to keep citrus psylla populations at acceptably low levels, they may contribute to reducing their numbers (Van den Berg et al., 1992). Cotton Cotton (Gossypium spp.) is an important agricultural product in South Africa, with commercial as well as developing farmers involved in its cultivation. The wide-scale introduction of Bt cotton has contributed significantly to improving yields and profitability of cotton production (Limpopo Province Freight Transport Data Bank, 2012). Several pests that attack cotton have a wide range of natural enemies, of which spiders are one prominent group (Van den Berg & DippenaarSchoeman, 1991). Spiders are common and occur in high numbers in cotton fields, preying on a variety of cotton pests. Plant-dwelling and ground-dwelling spiders were collected from 1979 to 1997 in five cotton-growing areas in South Africa using pittraps and the whole-plant bag technique (Dippenaar-Schoeman et al., 1999). Thirty-one families, represented by 92 genera and 127 species, were recorded during these surveys. Thomisidae were the most species-rich family with 21 species, followed by Araneidae (18 spp.) and Theridiidae (11 spp.). The most abundant spider species were Pardosa crassipalpis, Enoplognatha molesta, Mermessus fradeorum (Linyphiidae) and Misumenops rubrodecorata. Wandering spiders constituted 61.5% and webbuilders 38.5% of all spiders collected. In cotton fields under different management strategies in Mpumalanga (Mellet et al., 2006), a survey of the ground-dwelling spiders showed a dominance of Lycosidae (62.5%), Theridiidae (20.0%) and Linyphiidae (9.1%). Neither Bt-cotton nor chemically treated cotton showed long-term significant impacts on grounddwelling spiders. Spiders are also abundant on cotton in the USA and have been widely studied, with more than 300 species recorded (Whitcomb & Bell, 1964; Leigh & Hunter, 1969; Young & Lockley, 1985; Nyffeler et al., 1987a, b, 1989, 1992a, b). Macadamia South Africa is a large producer of macadamia (Macadamia integrifolia) nuts (Groenewald, 1999). About 60 insect and two mite species are known to attack macadamia trees and their fruit (Van den Berg et al., 2000). In South Africa, pentatomid and coreid stinkbugs are the most important pests in macadamia orchards (Van den Berg et al., 1999b). Infestation results in young nuts dropping and older nuts developing lesions. Arboreal spiders were collected over a 12-month period by canopy fogging in three macadamia orchards in the Mpumalanga Lowveld of South Africa. The spiders were sampled every 2
3 weeks, with 10 trees sampled in each orchard per sample date using dichlorvos as a knock-down spray (Dippenaar-Schoeman et al., 2001a, b). A total of 2778 specimens representing 21 families, 57 genera and 80 species were recorded. The Salticidae was very dominant, representing 72.7% of the total spiders collected, followed by the Sparassidae (6.9%), Hersiliidae (3.9%) and Araneidae (3.3%). The most diverse families were the Salticidae (17 spp.), Araneidae (16 spp.) and Thomisidae (11 spp.). Wandering spiders dominated the fauna, representing 95.8% of the total 4 Transactions of the Royal Society of South Africa Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 specimens collected, compared to 4.2% that were webbuilders. The salticid Thyene coccineovittata was the most abundant species and represented 29.7% of all the spiders collected, followed by T. natalli with 14.2%, Viciria alba with 8.6% and Tusitala guineensis with 8.3%. These four species were present in all three orchards throughout the year. Maize Maize (Zea mays) is the most important grain crop in South Africa, being both the major fodder grain and staple food of the majority of the South African population. After more than a decade of production, the cultivation of GM maize in South Africa has increased dramatically. During the 2010/2011 production season, GM maize contributed to 80% or 1.9 million ha of the total commercial area planted to maize (Department of Agriculture, Forestry and Fisheries (DAFF), 2011b). Maize is attacked by several pest species, of which the most serious is the maize stalk borer, Busseola fusca (Lepidoptera: Noctuidae), which can cause enormous crop losses. Other very important maize pests in South Africa are the noctuid cutworms (Euxoa and Agrotis species) (Du Plessis, 2003). Although spiders have been studied on maize in South Africa, as well as overseas, very little is known of the South African fauna. Midega et al. (2008) sampled ground-dwelling spiders in South African and Kenyan maize using a combination of pitfall traps and soil samples. They collected a total of 284 spiders in South Africa, with the Lycosidae the most abundant family. A second, unpublished survey was undertaken on the farm Buiteplaas in the Delmas district in Mpumalanga Province, South Africa during the 2004
2005 and 2005
2006 summer growing seasons. Three treatments were evaluated, namely Bt maize, conventionally sprayed maize, and unsprayed maize. Pitfall traps were used to sample the spiders (M. van Jaarsveld, personal communication, 2006). Fourteen families were collected, representing 32 genera and 38 species. The Linyphiidae, represented by four species, occurred in the highest numbers, with the Lycosidae, represented only by Pardosa crassipalpis, second. Pine plantations In many areas of Africa, the planting of exotic trees has superseded the area covered by indigenous forests. This has an effect on the vegetation structure at ground level, which should have an effect on the community structure of the ground-living spider fauna. Since spiders are important components of forest floor ecosystems as invertebrate predators (Moulder & Reichle, 1972), this could have significant secondary effects on other invertebrate groups and plants as well. Plantations exceed a million hectares in South Africa alone. As only a fraction of South Africa’s area (0.2%) is covered by tall evergreen indigenous forest (Huntley, 1984), their conservation and that of their cryptofauna is of utmost importance and should receive high priority for conservation efforts (Dippenaar-Schoeman et al., 2006). Two spider surveys in pine plantations have been undertaken in South Africa to date. The first was done in a pine plantation at Sabie in the Mpumalanga Province, South Africa (Van den Berg & Dippenaar-Schoeman, 1988). Of the 1484 spiders collected, 38.5% belonged to Miturgidae, 13% to the Lycosidae, 10% Tetragnathidae and 8% Salticidae. A second survey was undertaken at Ngome Forest, situated on the escarpment of northern KwaZulu-Natal, South Africa (Van der Merwe et al., 1996). This survey of ground-living spiders was conducted over a one-year period using 180 pitfall traps (36 per habitat). The survey covered five different habitat types: grassland, open indigenous forest, dense indigenous forest, ecotone and pine plantation. A total of 9360 spiders, represented by 136 species, were trapped. Pine had the lowest spider species richness while grassland had the highest species richness. Due to the large variation in species richness within habitat types, the results from this study did not convincingly support the notion that pine plantations have a lower ground-living spider diversity than indigenous habitats. However, cluster analysis of the sampling grids showed that different habitat types supported different spider assemblages (Van der Merwe, 1994). Pistachio Pistachio (Pistacia vera) was established as a new crop in South Africa during the 1990s as part of an investment by the Industrial Development Corporation in the Prieska district in the Northern Cape Province. As part of a larger biomonitoring programme in these orchards, intended to identify local and introduced pests and their potential biological control agents, spiders were selected as a target group representing the generalist predators forming part of the natural enemy complex in the orchards. Surveys were undertaken at ground level using pitfall traps and hand collecting, from the ground covers by sweep-netting, and from the tree canopies using canopy fogging, in three orchards of contrasting size and age. The pitfalls yielded 1692 spiders, representing 16 families and 49 species (Haddad & Dippenaar-Schoeman, 2006). Active searching yielded 645 spiders, representing 16 families and 63 species. Four families (Linyphiidae, Gnaphosidae, Lycosidae and Salticidae) dominated the epigeic fauna, collected by both sampling methods, but their abundance varied considerably between the two techniques. The sheet-web spider Ostearius melanopygius (Linyphiidae) dominated the fauna sampled by both techniques in all three orchards, and can be considered an agrobiont. In the ground covers, 1760 spiders representing 55 species were collected in the three orchards. Two species, Peucetia viridis (Oxyopidae) and Heliophanus pistaciae (Salticidae), dominated the spider fauna, accounting for 29.3% and 23.4% of the total, respectively (Haddad et al., 2004a). In total, 5843 spiders were collected from the tree canopies, representing 18 families and 88 species (Haddad et al., 2005). Three species dominated the spider fauna: H. pistaciae (53.4%), Cheiracanthium furculatum (12.7%) and Neoscona subfusca (Araneidae, 6.4%). Based on observations in the field, H. pistaciae and C. furculatum prey on at least seven orders of arthropods, while the web-building N. subfusca captured five different orders of arthropods in their webs. All three species preyed on thrips (Thysanoptera: Phlaeothripidae), seed bugs (Hemiptera: Lygaeidae), aphids (Homoptera: Aphididae) and leafhoppers (Homoptera: Cicadellidae), all of which have potential to cause damage to pistachio leaves and nuts (Haddad, 2003). In laboratory and field experiments, H. pistaciae was found to have a restricted role as a predator of Nysius natalensis (Hemiptera: Lygaeidae), showing a preference for Drosophila melanogaster (Diptera: Drosophilidae) in laboratory feeding trials (Haddad et al., 2004b). Nysius natalensis was shown to cause direct damage to pistachio nuts through the puncture wounds caused by its feeding, as well as through the Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 A.S. Dippenaar-Schoeman et al.: Knowledge of Spider Diversity in Agroecosystems dissemination of fungal pathogens to the nuts that result in further damage to the kernels (Swart, 2002). Based on these results, it is clear that the older orchards had greater species richness and abundance of spiders in all three strata compared to the more recently established orchards, largely due to natural succession. Furthermore, orchard establishment appears to have a distinct negative effect on spider species richness and abundance when compared to the assemblages from surrounding natural habitats, which had a much greater abundance and species richness (Haddad et al., 2008), and may ultimately reach abundance and richness levels comparable to natural habitats. Surprisingly, the ground-dwelling orchard fauna in South Africa is very similar to that found in European orchards, but that from the surrounding natural habitat is very different to the assemblages found in natural habitats in Europe (Haddad et al., 2008). Strawberries Strawberry (Fragaria ananassa) production has increased greatly in South Africa during the last decade. The common red spider mite, Tetranychus cinnabarinus (Acari: Tetranychidae) causes serious damage to strawberries in South Africa. During surveys, Coates (1972) found that Dermaptera and Araneae were the most important predators of spider mites in strawberry beds. In continuation of his work, a bio-ecological study of spiders in strawberry beds was undertaken from 1972 to 1974 to determine the species present and elucidate their role as predators of mites (Dippenaar-Schoeman, 1976). Weekly counts of spiders were made and 28 genera representing 14 families were collected by hand. Of the 5059 spiders recorded during the two seasons, 70.3% belonged to the Lycosidae, and 28.0% to the Araneidae, Thomisidae, Clubionidae, Salticidae and Linyphiidae, combined. Spider densities ranged from 0.56/m2 during July 1972 to 13.52/m2 in February 1973 (Dippenaar-Schoeman, 1979). The most abundant species collected was Pardosa crassipalpis, which accounted for over 80% of all Lycosidae. The life cycle and some ecological aspects of this species, which is a predator of T. cinnabarinus, were studied (Dippenaar-Schoeman, 1977). When it comes to the control of mites by spiders, the three seasons (winter
summer) during which the planting, growing and ripening of the fruit takes place, are of prime importance, because the mite population usually begins to increase during the winter months. The spider families that develop their full potential with regard to numbers during this period are considered to be the more important groups in the natural control of these mites. In this regard, the Lycosidae is of major importance, while the Linyphiidae, Thomisidae, and to a lesser extent Clubionidae, Salticidae and Araneidae, may also exert some influence as predators. Tomatoes Tomatoes (Solanum lycopersicum) are the second most important vegetable crop grown in South Africa, after potatoes. They contributed approximately 25% to the gross value of production in 2011. The average household in South Africa consumes between five and ten tomatoes per week (DAFF, 2011a). Tomatoes are attacked by several insect and mite pest species (Myburgh, 1988). Several surveys have been undertaken in the tomatoproducing areas of Limpopo, North West and Gauteng Provinces in search of biological control agents of tomato pests (Krüger & Dippenaar-Schoeman, 2000). In addition, 5 tomato plants in greenhouses at the ARC-PPRI research station were screened regularly for insect and mite pests and their natural enemies. Insects, mites and spiders were collected using random plant inspection, as many pests tend to aggregate. Specimens were hand collected or captured through beating of plants and sweep nets. During these surveys, 356 spiders were sampled in total, representing 16 families, 50 genera and 62 species. Araneidae (34%) was the most species-rich family and also collected in the largest numbers. Unfortunately, most of the specimens were immature and could not be identified to species level. However, several of the species collected are known predators of spider mites. Vineyards Spiders are found in and around vineyards and prey on insect pests that are found associated with grapes (Vitis spp.). Although there is no information available regarding the spiders in vineyards in South Africa, Costello and Daane (1995, 1997, 2005) and Roltsch et al. (1998) found that spiders were by far the dominant predator group collected in grape vineyards in central California, and in some years spiders comprised over 95% of predators sampled. Eight species of spiders represented more than 90% of the fauna from central California, with two theridiids (Theridion dilutum and T. melanurum) the most abundant, followed by the miturgid Cheiracanthium inclusum (Miturgidae). Three unpublished surveys have been undertaken in grape vineyards in Southern Africa. The first was undertaken in 2008 on the border of Namibia and South Africa, where a total of 106 spiders representing eight species from six families were collected. Two species, Cheiracanthium furculatum and an unidentified Theridion sp. (Theridiidae), together constituted 86% of all the spiders collected. The second survey was conducted in the Cape Floristic Region of South Africa, where wine grape production and biodiversity conservation are of major importance, and innovative management of the landscape is necessary. A study was done in June and October 2006 using pitfall traps to look at the impacts of alternative farming methods, such as organic and biodynamic farming, on biodiversity. A total of 17 spider families represented by 42 species were sampled during this study (Gaigher, 2008). In 2011, vineyards in the Western Cape Province were surveyed and 940 spiders were sampled with paper traps or by hand to investigate their possible role in the transfer of vinestem virus (F. Halleen, personal communication, 2012). A total of 16 families and 52 species were sampled and the most abundant species was Cheiracanthium furculatum, followed by Euryopis episinoides (Theridiidae) and Pelecopsis janus (Linyphiidae). Although spiders may be of benefit as predators in vineyards, they may also pose problems as possible invasive species when they land in containers of table grapes and are inadvertently exported. When the grapes are harvested, some spiders escape detection during the packing process by hiding in silk retreats made in bunches of grapes. The grapes are chilled prior to export, causing the spiders to become dormant and immobile. Spiders are able to lower their metabolic rates, enabling them to survive long periods of exposure to low temperatures. When the exported containers are opened at the retailers or by consumers in recipient countries, the spiders try to escape after this period of inactivity. It is mainly members of the family Miturgidae (Cheiracanthium spp.) that 6 Transactions of the Royal Society of South Africa have been implicated in such scenarios (Dippenaar-Schoeman, 2007). Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 Spider families and agrobiont species Araneidae A total of 36 araneid species have been sampled from agroecosystems in South Africa (Appendix 1), but none of them were sufficiently abundant in any crop to be regarded as an agrobiont. On citrus, four species of araneids were observed to prey on the citrus psylla (Van den Berg et al., 1992), amongst which was an Araneus sp. Of the 18 species of araneids collected on cotton, most were rare except for Neoscona triangula, N. blondeli, N. subfusca and Nemoscolus obscurus, which were regularly found. Araneids were also the most abundant spiders collected from tomatoes. Araneids spin their webs between plants and feed on a variety of flying and jumping insects. Araneids were observed preying on Helicoverpa armigera (Lepidoptera: Noctuidae) moths and larvae, both in the laboratory and in the field (Dippenaar-Schoeman et al., 1999). Members of the Araneidae were also commonly found on cotton in other countries (Dean et al., 1982; Nyffeler et al., 1989), while Lincoln et al. (1967) found that species of Araneus were one of the most important predators of bollworm moths. Other pest species preyed on by araneid species (Kagan, 1943) include Adelphocoris rapidus nymphs and Pseudatomoscelis seriatus adults (Hemiptera: Miridae), Brevicoryne brassicae, Myzus cerasi, M. Iythri and Rhopalosiphum padi aphids (Hemiptera: Aphididae), H. armigera larvae and moths, and spur-throated locust nymphs. Linyphiidae Nineteen species have been sampled from crops in South Africa (Appendix 1) and two species could be recognized as agrobionts, namely the cosmopolitan species Ostearius melanopygius, which was abundant on cotton, maize and pistachio, and Eperigone fradeorum, which was abundant in cotton fields. On cotton, the Linyphiidae were mostly observed in small webs spun across the leaf lamina (Van den Berg, 1989). Eperigone fradeorum was the most common species, followed by Microlinyphia sterilis and O. melanopygius. Erigone irrita and M. sterilis were found in association with the red spider mite Tetranychus lombardinii on several vegetables (Smith-Meyer, 1996). In South African maize, the most abundant linyphiids were O. melanopygius, Meioneta habra and Limoneta sirimoni (Dippenaar-Schoeman, unpublished report, 1989). Ostearius melanopygius dominated the grounddwelling spider fauna sampled in pistachio orchards of contrasting size and age (Haddad & Dippenaar-Schoeman, 2006). In vineyards it was Pelecopsis janus that was the most abundant, followed by M. habra and L. sirimoni. Although no studies have been conducted in South African winter wheat, linyphiids often form the dominant group of generalist predators in European wheat and barley (Schmidt & Tscharntke, 2005; Öberg et al., 2008), where they are particularly important in the control of aphids (Sunderland et al., 1986a, b; Harwood et al., 2001, 2003). Some Iinyphiids have been observed to attack second-instar bollworm (Helicoverpa zea) larvae as they crawl up the main stems of cotton plants (Whitcomb, 1967). In Texas, Nyffeler et al. (1988) found that aphids were the dominant prey of the linyphiid Frontinella pyramitela. Lycosidae Twenty-three species of lycosids have been found in crops (Appendix 1) but only one species, Pardosa crassipalpis, was sampled in abundance from strawberry and cotton fields and could be considered an agrobiont in these crops. This species was also collected from several other agroecosystems but in lower numbers. Lycosids are cursorial hunters and were observed on the leaves and flowers of plants, or running on the ground and hiding under dry leaves in cotton fields (Van den Berg, 1989). The numerically dominant species, P. crassipalpis, was recorded from five cotton growing areas, and preyed on red spider mites and various stages of cotton bollworm larvae (Helicoverpa armigera) in the laboratory (Dippenaar- Schoeman et al., 1999). They are the dominant family at the ground level in Bt cotton fields, representing 62.5% of the spiders collected (Mellet et al., 2006). Lycosidae was the dominant spider family in strawberries, where P. crassipalpis was the dominant species present, representing 82% of all the lycosids sampled and 63% of all the spiders present (Dippenaar-Schoeman, 1979). The biology of this species was described by Dippenaar-Schoeman (1977). Lycosidae was also the most abundant family sampled from sugar cane in South Africa (Leslie & Boreham, 1981). During this study, the authors conducted cross-over electrophoresis on the stomach contents of arthropods sampled on sugar cane, and determined that ants and spiders were the most common predators that fed on the sugarcane borer, Eldana saccharina (Lepidoptera: Pyralidae). Coates (1974), Dippenaar-Schoeman (1976) and Botha (1986) found P. crassipalpis to be active predators of red spider mites in various crops in South Africa. In the USA, Whitcomb et al. (1963) found that Iycosids swarm over cotton plants at night in summer and that Pardosa spp. prey on pink bollworm moths. They presumably destroy first and second-instar larvae of the bollworm on the plant, as well as those that fall to the ground. Bollworm moths are also vulnerable to predation during their brief exposure on the soil surface following emergence from their pupae (Lincoln et al., 1967; Whitcomb, 1967). Laboratory studies on feeding strategies of Pardosa hortensis showed that they can play a positive role in controlling agricultural pests in a density-sensitive way (Samu & Bı́ró, 1993). Lycosids also prey on Helicoverpa pupae (Lincoln et al., 1967), cabbage looper moths (Whitcomb & Bell, 1964), Heliothis virescens (Lepidoptera: Noctuidae) and Lygus Iineolaris (Hemiptera: Lygaeidae) (Hayes & Lockley, 1990). Miturgidae Seven species of sac spiders were commonly found on crops (Appendix 1). Cheiracanthium furculatum is the dominant sac spider recorded from crops in South Africa and is an agrobiont species in vineyards and pistachio nuts. It is also the dominant sac spider recorded from citrus in South Africa, and Van den Berg et al. (1992) observed that they prey mainly on the citrus mite Panonychus ulmi (Acari: Tetranychidae), killing 29.3 mites/ spider/day. Their silk retreats, which are usually constructed between rolled up leaves for resting, frequently trap citrus psylla (Van den Berg et al., 1992). Two species, C. furculatum and C. africanum, were occasionally collected during cotton surveys. They are aggressive spiders and kill any prey that they encounter, although not always feeding on them. According to Brettell & Burgess (1973), C. furculatum was frequently found in the narrow space between the bract and boll of cotton in Zimbabwe. In the laboratory they preyed on all larval stages of the cotton bollworm. Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 A.S. Dippenaar-Schoeman et al.: Knowledge of Spider Diversity in Agroecosystems The genus Cheiracanthium is one of the most common genera found on cotton in the USA (Whitcomb & Bell, 1964; Young & Lockley, 1985), Australia (Bishop & Blood, 1981), Israel (Mansour, 1987), Zimbabwe (Brettell & Burgess, 1973) and South Africa (Dippenaar-Schoeman et al., 1999). Carroll (1980) found that they prey on citrus thrips, mites, insect eggs and lepidopterous larvae, and that they are probably the most promising natural enemies of citrus pest arthropods in California. Cheiracanthium species have been reported to prey on second and third instars of Helicoverpa spp. larvae, cotton looper larvae, green vegetable bug and cotton seed bug in cotton (Bishop & Blood, 1981). They also feed preferentially on abundant pests during pest outbreaks, and show a direct numerical relationship with changes in Helicoverpa spp. larval abundance (Bishop, 1979). McDaniel & Sterling (1982) found that an individual consumed on average 14.2 Heliothis virescens eggs in the laboratory during a 24-hour period. Feeding studies in Israel showed that C. mildei are important predators of red spider mites (T. cinnabarinus). During feeding studies in the laboratory, females of C. mildei on average preyed on 27.5 mites per day and C. mildei juveniles on 18.8 mites per day. In contrast, the predacious mite Phytoseiulus persimilis (Acari: Phytoseiidae), which is extensively used in biological control, has been reported to prey on only 11.3 mites per day (Mansour et al., 1995). Oxyopidae Nine oxyopid species have been sampled from crops in South Africa (Appendix 1). Oxyopids are diurnal and nocturnal cursorial hunters that are found on cotton plants, frequently near the flowering parts (Van den Berg, 1989). Oxyopes bothai was occasionally found in all the cotton areas sampled. Peucetia viridis dominated the ground cover fauna in two of three pistachio orchards in the Northern Cape, and can be considered an agrobiont, while O. bothai and O. hoggi were low in abundance in the three orchards sampled (Haddad et al., 2004a). All three species occurred in the pistachio canopies but were low in abundance (Haddad et al., 2005). Oxyopids were consistently among the most abundant arthropod predators in cotton agroecosystems in the USA (Young & Lockley, 1985; Nyffeler et al., 1987a,b; 1992a). According to Nyffeler et al. (1987a), 0.12 million prey may be killed per week per hectare by O. salticus spiders in unsprayed cotton. In sprayed fields, spider density is often strongly reduced, reducing their impact on pests. Whitcomb (1967) found that Oxyopes spp. destroyed more second-instar larvae of Helicoverpa zea than did any other arthropod predator in cotton. They also preyed on mirids, cotton leafhoppers, tarnished plant bugs (Whitcomb et al., 1963), Adelphocoris rapidus (adults), Pseudatomoscelis seriatus adults, and aphids (Kagan, 1943; Nyffeler et al., 1992b). In Australia, Bishop & Blood (1981), found that O. mundulus fed preferentially on Helicoverpa larvae during outbreaks and showed a numerical response to changes in Helicoverpa larval abundance. In feeding experiments in Israel, oxyopids consumed, on average, 16.8 red spider mites per day in the laboratory (Mansour et al., 1995). Salticidae A total of 70 salticid species have been sampled from crops (Appendix 1). Although salticids are a common part of the predator complex in most agroecosystems, their species composition and numbers vary between crops and between regions. For example, salticids are sometimes the dominant 7 family present on citrus (Van den Berg et al., 1987, 1992), but are less abundant on cotton (Dippenaar-Schoeman et al., 1999; Mellet et al., 2006) and strawberries (Dippenaar-Schoeman, 1976). In orchard crops particulartly, Salticidae has been shown to be an important component of spider assemblages, where several species are agrobionts. In a knock-down study of three macadamia orchards in the Mpumalanga Lowveld in South Africa, 73% of the sampled spiders were salticids, and four species together represented more than 61% of all spiders collected. Thyene coccineovittata was the most abundant species and represented 30% of all the spiders collected, followed by T. natali with 14%, Viciria alba with 9% and Tusitala guineensis with 8%. These four species were present throughout the year in all three orchards sampled (Dippenaar-Schoeman et al., 2001a, b). On avocado in Mpumalanga, salticids comprised 31.0% of the spiders collected, and two of the four most abundant species were salticids, viz. Thyene coccineovittata (11.5%) and T. natali (11.0%). In citrus orchards in Mpumalanga, salticids accounted for 34.0% of all spiders collected (Van den Berg et al., 1987, 1992). In pistachio orchards in the Northern Cape, the fauna of ground covers in pistachio orchards was dominated by Salticidae (31.8%), with Heliophanus pistaciae (23.4%) and Phlegra karoo (5.8%) the most abundant species (Haddad et al., 2004a). In pistachio canopies, salticids accounted for 59.2% of the spiders collected, with H. pistaciae by far the most abundant species, accounting for 53.4% of the spiders collected (Haddad et al., 2005). On the ground surface, salticids accounted for 20.0% of the spiders collected in pitfall traps and 15.4% of the spiders collected by hand, with P. karoo the most abundant salticid collected by both methods (Haddad & Dippenaar-Schoeman, 2006). As H. pistaciae is found in multiple habitat strata in high abundance, and occurs throughout the year in the orchards, it can be considered a pistachio agrobiont (Haddad & Louw, 2006). Regarding field crops, various salticid genera were found in cotton. They were common in all five areas sampled and were found both in pit-traps and on plants, where they constructed sacs in rolled-up leaves (Van den Berg, 1989). Most salticids are diurnal and their prey is limited to species present on the cotton plants. In the laboratory, a single salticid devoured 17 red spider mites within a 12-minute period and also preyed on the first two larval stages of the cotton bollworm Helicoverpa armigera (Dippenaar-Shoeman et al., 1999). Van den Berg et al. (1987, 1992) observed several salticid species of the genera Myrmarachne, Hyllus and Thyene preying on adult citrus psylla in citrus orchards (Dippenaar-Schoeman, 2001). In pistachio orchards, Heliophanus pistaciae was found to have a limited role as a predator of the lygaeid bug Nysius natalensis (Haddad et al., 2004b), although it does feed on a variety of different arthropods and may play a role in their biological control (Haddad, 2003). Studies elsewhere in the world indicate that salticids prey on a variety of insect and mite species, and that predation is not limited to adult prey but includes the eggs and larval or nymphal stages as well (Whitcomb, 1974; Nyffeler et al., 1994a). Salticidae are highly polyphagous but can narrow their prey spectrum when prey becomes available in high numbers (Nyffeler et al., 1994a). Studies indicate that they prey on several insect and mite species in citrus. Edwards (1981) and Mansour et al. (1982) reported salticids preying on citrus weevils, and Carroll (1980) recorded thrips, mites and midges as prey of salticids. Feeding experiments conducted in Israel showed salticids to consume on average 10.1 red spider mites 8 Transactions of the Royal Society of South Africa Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 per day (Mansour et al., 1995). In US cotton fields, salticids prey on bollworms (first to third instar larvae), boll weevils, robber flies (Whitcomb & Bell, 1964), Helicoverpa armigera larvae, Alabama argillacea (Lepidoptera: Noctuidae) larvae and adults, and nymphs of Adelphocoris rapidus (Kagan, 1943). They seize second-instar larvae of H. zea from cotton foliage and under bracts of squares and bolls of the plant (Whitcomb, 1967; Young, 1989) and are able to destroy large numbers of first and second-instar larvae in the field (Lincoln et al., 1967). Theridiidae Gumfoot-web spiders build webs on, between and around leaves. Twenty-one species have been sampled from crops in South Africa (Appendix 1). Theridion purcelli and Enoplognatha molesta were the most abundant theridiids found in citrus orchards in South Africa (Van den Berg et al., 1992). This corresponds well with the findings of Mansour & Whitcomb, (1986), who found that 34% of spiders in the undercover of citrus groves in Israel belong to the genus Theridion. In cotton fields, E. molesta was the most common species, followed by T. purcelli (Dippenaar-Schoeman et al., 1999). In the laboratory both species fed on red spider mites, the first three larval stages and adult stages of Helicoverpa armigera, leafhoppers and aphids. Van den Berg et al. (1992) observed that Achaearanea sp., Enoplognatha sp. and two Theridion spp. frequently spun their webs close to the leaf surface in citrus trees. Citrus psylla nymphs and adults crawl into the webs, where they are caught and eaten. In the laboratory at ARCPPRI, it was also observed that they feed on red spider mites (Dippenaar-Schoeman et al., 1999). Theridiids are important predators of several insect pest species (Mansour & Whitcomb, 1986). In Israel, Mansour et al. (1995) found that a Steatoda sp. was able to prey on 9.5 Tetranychus cinnabarinus mites per day in the laboratory. In cotton, they have been found to prey on boll weevils and bollworm larvae (Whitcomb & Bell, 1964). Prey records of Theridion australe and Tidarren haemorrhoidale, often found on cotton in Texas, showed aphids to be their main prey (Nyffeler et al., 1988). In Australia, Achaearanea veruculata was observed to prey on jassids, cotton aphids, looper larvae and cotton seed bugs (Bishop & Blood, 1981). Thomisidae Fourty-four thomisids were sampled from crops (Appendix 1). A total of 18 species were collected from citrus in South Africa, with Misumenops rubrodecoratus the most common. Van den Berg et al. (1992) observed that M. rubrodecoratus prey on adult citrus psylla, and feeding experiments indicated that they also prey on aphids, red spider mites and thrips (Dippenaar-Schoeman, unpublished data, 1998). On cotton, M. rubrodecoratus are mostly found on leaves and stems, near bracts of cotton plants, as well as hiding under dry leaves on the ground (Van den Berg, 1989); M. rubrodecoratus was the most abundant species collected in five cotton growing areas. In the laboratory they preyed on red spider mites, the first two larval stages of Helicoverpa armigera, as well as on aphids (Dippenaar-Schoeman et al., 1999). In two cotton fields in Arizona, USA, Misumenops celer occurred in high numbers and constituted a major portion (44.2
57.6%) of the predator complex (Plagens, 1983). Oxytate argenteooculata was the most abundant species on avocado trees and represented 22.2% of all spiders collected (Dippenaar-Schoeman et al., 2005). They are less abundant in other crops. Thomisids are active during the day (Leigh & Hunter, 1969) and prey on a variety of small invertebrates, potentially playing an important role in the natural control of pests such as aphids, red spider mites and thrips (Bogya, 1999). Several studies have highlighted the importance of thomisids in biological control in cotton fields. Lincoln et al. (1967) found Misumenops spp. on all parts of the plant, especially on or under bracts of cotton bolls and squares, although very few were taken from the ground. They capture second-instar larvae of H. zea in cotton terminals, where they wait in ambush (Whitcomb, 1967). They also prey on several other insects, including Geocoris punctipes (Hemiptera: Geocoridae), Lygus lineolaris (Hemioptera: Lygaeidae), Acalymna vittata (Coleoptera: Chrysomelidae) (Lincoln et al., 1967), syrphid flies and beetles (Whitcomb & Bell, 1964), Pseudatomoscelis seriatus adults (Dean et al., 1987), and larvae of Alabama argillacea and H. armigera (Kagan, 1943). In China, they have been observed to feed on eggs and first instar larvae of H. armigera (Wu et al., 1981). CONCLUSION Spiders are common and occur in fairly high numbers in agroecosystems in South Africa where they form part of the natural enemy complex as generalist predators. Their presence in crops should be encouraged and steps taken to protect them from potentially lethal pesticides. Owing to the different guilds they occupy, various families are affected differently by pesticides (Pekár & Haddad, 2005). Judicious use of pesticides in crop programmes may result in more complex and abundant spider communities, thereby augmenting biological pest control. Although spiders may be incapable of controlling major pest outbreaks by themselves, their role in a complex predator community could be important to regulate pest species at low densities early in the season and between peaks of pest species activity. They could therefore play an important role in keeping pests at endemic levels and preventing outbreaks. It is important that farmers and students be made aware of their role. ACKNOWLEDGEMENTS We thank the ARC-Plant Protection Research Institute for providing the opportunity and the facilities for most of these investigations. The technical assistance and helpfulness of the staff at the different research stations is greatly appreciated. We also want to thank all the people who assisted at various times with fieldwork and for their encouragement. Vaughn Swart (University of the Free State) is also thanked for providing spider material from pecan nut orchards for inclusion in this study. REFERENCES ANDERSON, J.F. 1974. Responses to starvation in the spiders Lycosa lenta Hentz and Filistata hibernalis (Hentz). Ecology 55: 576
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12. 12 Transactions of the Royal Society of South Africa APPENDIX 1. SPIDER SPECIES COLLECTED IN AGROECOSYSTEMS IN SOUTH AFRICA. Guild abbreviations: BGW
Burrow ground dweller; FWB
Funnel-web; GW
Ground wanderer; PW
Plant wanderer; RWB
Retreat-web; GWB
Gumfoot-web; OWB
Orb-web; SpWB
Space-web; ShWB
Sheet-web. *agrobiont species. Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 Species AGELENIDAE Agelena gaerdesi Roewer, 1995 Benoitia ocellata (Pocock, 1900) AMAUROBIIDAE Pseudauximus annulatus Purcell, 1908 AMMOXENIDAE Ammoxenus amphalodes Dippenaar & Meyer, 1980 Ammoxenus coccineus Simon, 1893 ARANEIDAE Aethriscus olivaceus Pocock, 1902 Arachnura scorpionoides Vinson, 1863 Araneus apricus Karsch, 1884 Guild Crops FWB pistachio FWB maize RWB citrus, pistachio, maize GW cotton GW cabbage, pistachio OWB avocado OWB macadamia OWB Araneus holzapfelae Lessert, 1936 Araneus nigroquadratus Lawrence, 1937 Argiope australis (Walckenaar, 1805) OWB avocado, citrus, macadamia, tomatoes avocado, tomatoes OWB pine plantations, tomatoes OWB Argiope trifasciata (Forskål, 1775) Caerostris sexcuspidata (Fabricius, 1973) Chorizopes sp. Cyclosa insulana (Costa, 1834) Cyclosa oculata (Walckenaer, 1802) Cyphalonotus larvatus (Simon, 1881) Cyrtophora citricola (Forskål, 1775) OWB OWB avocado, peach, pine plantations, pistachio, pumpkin cotton, kenaf, lucerne, tomatoes apple, citrus, pine plantations, tomatoes citrus avocado, citrus, tomatoes citrus, cotton, macadamia, potatoes avocado, citrus, macadamia citrus, lemon, pine plantations, pistachio, prickly pear, tomatoes citrus OWB OWB strawberry citrus, potatoes OWB OWB OWB citrus, tomatoes potatoes, pumpkin cotton OWB avocado, pecans, tomatoes OWB sugar cane OWB citrus, cotton, pistachio OWB avocado, cotton, pecans, pistachio, tomatoes, vineyards avocado, cotton, lucerne, maize, pecans, pistachio, tomatoes Gasteracantha versicolor (Walckenaer, 1842) Gea infuscata Tullgren, 1910 Hypsosinga lithyphantoides (Walckenaer, 1802) Isoxya tabulata (Thorell, 1859) Kilima decens (Blackwall, 1866) Larinia natalensis (Grasshoff, 1971) Lipocrea longissima (Simon, 1881) Mahembea hewitti (Lessert, 1930) Nemoscolus elongatus Lawrence, 1947 Neoscona blondeli (Simon, 1885) Neoscona moreli (Vinson, 1863) OWB OWB OWB OWB OWB OWB OWB APPENDIX 1 (Continued ) Species Guild Crops Neoscona hirta (C.L. Koch, 1844) Neoscona quincasea Roberts, 1983 Neoscona rapta (Thorell, 1899) Neoscona rufipalpis (Lucas, 1858) Neoscona subfusca (C.L. Koch, 1837) OWB vineyards OWB pine plantations, vineyards OWB OWB pistachio avocado, citrus, macadamia avocado, citrus, cotton, grapefruit, macadamia, pecans, pine plantations, pistachio, tomatoes, vineyards avocado, macadamia, onion, pecans, sorghum, tomatoes citrus OWB Neoscona triangula (Keyserling, 1864) OWB Paraplectana walleri (Blackwall, 1865) Pararaneus cyrtoscapus (Pocock, 1898) Pararaneus perforatus (Thorell, 1899) Pararaneus spectator (Karsch, 1885) Prasonica seriata Simon, 1895 Singa albodorsata Kauri, 1950 ARCHAEIDAE Afrarchaea godfreyi (Hewitt, 1919) Afrarchaea ngomensis Lotz, 1996 CAPONIIDAE Caponia chelifera Lessert, 1936 CLUBIONIDAE Clubiona abbajensis Strand, 1906 Clubiona africana Lessert, 1921 OWB Clubiona annuligera Lessert, 1929 Clubiona pupillaris Lawrence, 1938 CORINNIDAE Afroceto arca Lyle & Haddad, 2010 Afroceto martini (Simon, 1897) Cambalida dippenaarae Haddad, 2012 Cambalida fulvipes (Simon, 1896) Castianeira sp. OWB OWB avocado, citrus, pistachio, tomatoes maize OWB maize, strawberries OWB OWB pistachio, tomatoes tomatoes GW pine plantations GW pine plantations GW cotton, pine plantations PW PW avocado, citrus, lemon, macadamia avocado, citrus, macadamia, tomatoes, vineyards maize PW citrus, cotton GW citrus GW GW macadamia, pistachio citrus, cotton, grapefruit, maize maize, pistachio PW GW GW Copa flavoplumosa Simon, 1885 GW Copuetta lacustris (Strand, 1916) Corinnomma semiglabrum (Simon, 1896) Fuchiba aquilonia Haddad & Lyle, 2008 Graptartia mutillica Haddad, 2004 Hortipes luytenae Bosselaers & Ledoux, 1998 Hortipes merwei Bosselaers & Jocqué, 2000 Hortipes schoemanae Bosselaers & Jocqué, 2000 Orthobula radiata Simon, 1897 GW cotton, pistachio, sunflower, tomatoes avocado, citrus, cotton, macadamia, maize, pistachio, strawberries maize, pistachio, vineyards GW citrus GW citrus GW maize GW pine plantations GW pine plantations GW pine plantations GW cotton A.S. Dippenaar-Schoeman et al.: Knowledge of Spider Diversity in Agroecosystems Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 APPENDIX 1 (Continued ) 13 APPENDIX 1 (Continued ) Species Guild Crops Species Guild Crops Poachelas striatus Haddad & Lyle, 2008 Pronophaea natalica Simon, 1897 Pronophaea sp. Thysanina capensis Lyle & Haddad, 2006 Thysanina transversa Lyle & Haddad, 2006 Trachelas pusillus Lessert, 1923 CTENIDAE Anahita sp. Ctenus pulchriventris (Simon, 1896) CYATHOLIPIDAE Isicabu zuluensis Griswold, 1987 Ulwembua denticulata Griswold, 1987 CYRTAUCHENIIDAE Ancylotrypa pusilla (Purcell, 1903) Ancylotrypa sp. Ancylotrypa vryheidensis (Hewitt, 1915) Homostola zebrina Purcell, 1902 DEINOPIDAE Deinopis cornigera Gerstäcker, 1873 Menneus camelus Pocock, 1902 DICTYNIDAE Archaeodictyna sp. Dictyna sp. GW maize GW macadamia, pear, pistachio GW pine plantations GW pistachio GW GW cotton pine plantations GW cabbage GW macadamia PW cotton, maize, pistachio, tomatoes GW GW GW GW pistachio maize cotton, pistachio mango, pine plantations, pistachio citrus, cotton, pistachio GW GW maize citrus, maize, pine plantations, strawberries Drassodes lophognathus Purcell, 1907 Drassodes sesquidentatus Purcell, 1908 Drassodes stationis Tucker, 1923 Echemus erutus Tucker, 1923 Ibala arca (Tucker, 1923) Ibala bilinearis (Tucker, 1923) Latonigena africanus Tucker, 1923 Megamyrmaekion transvaalense Tucker, 1923 Micaria sp. OWB pine plantations OWB avocado, citrus GW pistachio GW GW cotton, maize pine plantations GW pine plantations OWB avocado OWB avocado DYSDERIDAE Dysdera crocata C.L. Koch, 1838 ERESIDAE Stegodyphus dumicola Pocock, 1898 GALLIENIELLIDAE Austrachelas bergi Haddad, Lyle, Bosselaers & Ramirez, 2009 Austrachelas natalensis Lawrence, 1942 GNAPHOSIDAE Aneplasa nigra Tucker, 1923 Asemesthes ceresicola Tucker, 1923 Asemesthes decoratus Purcell, 1908 Asemesthes lineatus Purcell, 1908 Asemesthes purcelli Tucker, 1923 Camillina aldabrae (Strand, 1907) Camillina cordifera (Tullgren, 1910) Camillina corrugata (Purcell, 1907) Camillina setosa Trucker, 1923 Drassodes ereptor Purcell, 1907 RWB RWB pistachio cabbage, citrus, cotton, tomatoes GW pear RWB citrus GW avocado GW tomatoes GW GW pistachio cotton, tomatoes GW cotton GW pistachio GW pistachio GW maize GW GW citrus, cotton, maize, pistachio, sunflower pistachio GW sugar cane GW pistachio Nomisia varia (Tucker, 1923) Odontodrassus aphanes (Thorell, 1897) Poecilochroa capensis Strand, 1909 Pterotricha auris (Tucker, 1923) Pterotricha varius (Tucker, 1923) Scotophaeus relegatus Purcell, 1907 Setaphis browni (Tucker, 1923) Setaphis subtilis (Simon, 1897) Trachyzelotes jaxartensis (Kroneberg, 1875) Trephopoda hanoveria Tucker, 1923 Upognampa biamenta Tucker, 1923 Upognampa parvipalpa Tucker, 1923 Urozelotes rusticus (L. Koch, 1872) Xerophaeus capensis Purcell, 1907 Xerophaeus pallidus Tucker, 1923 Xerophaeus vickermani Tucker, 1923 Zelotes bastardi (Simon, 1896) Zelotes corrugatus (Purcell, 1907) Zelotes frenchi Tucker, 1923 Zelotes fuligineus (Purcell, 1907) Zelotes humilis (Purcell, 1907) Zelotes natalensis Tucker, 1923 Zelotes oneilli (Purcell, 1907) Zelotes pallidipes Tucker, 1923 Zelotes sclateri Tucker, 1923 Zelotes scrutatus (O.P.Cambridge, 1872) Zelotes uquathus Fitzpatrick, 2007 HAHNIIDAE Hahnia lobata Bosmans, 1981 Hahnia schubotzi Strand, 1913 Hahnia tabulicola Simon, 1898 HERSILIIDAE Hersilia sericea Pocock, 1898 Tyrotama bicava (Smithers, 1945) GW GW GW GW apple, maize, pistachio, potatoes pistachio cotton GW pistachio GW GW maize, pistachio, vineyard pistachio GW cotton, vineyard GW GW GW cotton, pistachio cabbage, citrus, cotton, maize, pistachio, tomatoes cotton, grapefruit, minneola GW pistachio GW vineyards GW cotton GW cabbage GW vineyards GW pine plantations GW pistachio GW GW cabbage, cotton pistachio GW GW cotton citrus, pistachio GW GW GW pine plantations avocado, citrus, cotton, sunflower pistachio cotton tomatoes citrus, cotton, maize, pistachio, sunflower citrus SWB SWB SWB pine plantation apple cotton, maize PW avocado, citrus, grapefruit, macadamia cotton GW GW GW GW PW 14 Transactions of the Royal Society of South Africa APPENDIX 1 (Continued ) Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 Species IDIOPIDAE Ctenolophus fenoulheti Hewitt, 1913 Gorgyrella schreineri Purcell, 1903 LINYPHIIDAE Ceratinopsis dippenaari Jocqué, 1984 Ceratinopsis idanrensis Locket & Russell-Smith, 1980 Erigone irrita Jocqué, 1984 Erigone prominens Bosenberg & Strand, 1906 Limoneta sirimoni (Bosmans, 1979) Meioneta habra Locket, 1968 Meioneta natalensis Jocqué, 1984 Meioneta prosectes Locket, 1968 Meioneta prosectoides Locket & Russell-Smith, 1980 Mermessus fradeorum (Berland, 1932) Metaleptyphantes familiaris Jocqué, 1984 Metaleptyphantes perexiguus (Simon & Fage, 1922) Microlinyphia sterilis (Pavesi, 1883) Ostearius melanopygius (O.P.Cambridge, 1879)* APPENDIX 1 (Continued ) Guild Crops GW cotton GW pistachio SWB citrus SWB cotton SWB SWB SWB citrus, cotton cotton, maize, strawberries, tomatoes lucerne, maize, strawberries cotton, lucerne, maize, minneola, pecans, pistachio, strawberries, sunflowers, tomatoes cotton, pine plantations SWB potatoes SWB cotton SWB cotton, tomatoes kenaf, pistachio apple, cotton, lucerne, pistachio citrus, cotton SWB SWB SWB SWB SWB SWB avocado, cotton, kenaf, lucerne, pecans, pistachio, strawberries apple, cabbage, citrus, cotton, maize, pistachio, strawberries, tomatoes, vineyards cotton, kenaf, lucerne, maize, pistachio, sorghum, vineyards citrus SWB cotton, kenaf, potatoes SWB citrus, cotton GW pistachio SWB Pelecopsis janus Jocqué, 1984 SWB Tybaertiella convexa (Holm, 1962) Tybaertiella krugeri (Simon, 1894) Typhistes gloriosus Jocqué, 1984 LIOCRANIDAE Rhaeboctesis trinotatus Tucker, 1920 LYCOSIDAE Allocosa lawrencei (Roewer, 1951) Allocosa tuberculipalpa (Caporiacco, 1940) Amblyothele ecologica RussellSmith, Jocqué & Alderweireldt, 2009 Arctosa promontorii (Pocock, 1900) Evippa sp. Evippomma squamulatum (Simon, 1898) Foveosa foveolata (Purcell, 1903) Hippasa affinis Lessert, 1933 Hogna bimaculata (Purcell, 1903) Hogna spenceri (Pocock, 1898) GW vineyards GW citrus, grapefruit GW tomatoes GW vineyards GW GW pistachio pistachio GW citrus, pistachio GW GW maize cotton GW cotton Species Guild Crops Hogna transvaalica (Simon, 1898) Lycosa sp. Ocyale guttata (Karsch, 1878) Pardosa crassipalpis Purcell, 1903* GW cotton, maize, strawberries GW GW GW GW GW GW strawberry tomatoes apple, cabbage, citrus, cotton, lucerne, maize, pear, pecans, pine plantations, pistachio, potatoes, sorghum, strawberries, sugar cane, sunflower, tomatoes litchi, strawberries cotton pistachio, vineyards GW vineyards GW cotton GW cotton, maize, tomatoes GW GW pistachio cotton GW maize GW pine plantations GW pine plantations PW avocado, citrus, cotton, pine plantations PW cotton PW PW avocado, citrus, cotton, lucerne, macadamia, maize, mango, pecans, pistachio, potatoes, strawberries, tomatoes, vineyards maize PW cotton, pistachio PW PW avocado, citrus, minneola, tomatoes macadamia PW pine plantations OWB citrus, prickly pear GWB macadamia, maize, sunflower, tomatoes GW citrus GW pine plantations GW cotton, pine plantations, sunflower GW pistachio GW pine plantations Pardosa oncka Lawrence, 1927 Pardosa umtalica Purcell, 1903 Pterartoria arbuscula (Purcell, 1903) Pterartoriola sagae (Purcell, 1903) Schizocosa darlingi (Pocock, 1898) Trabea natalensis RussellSmith, 1982 Trabea purcelli Roewer, 1951 Trochosa albipilosa (Roewer, 1960) Zenonina mystacina Simon, 1898 MICROSTIGMATIDAE Microstigmata longipes (Lawrence, 1938) Microstigmata zuluensis (Lawrence, 1938) MIMETIDAE Mimetus natalensis Lawrence, 1938 MITURGIDAE Cheiracanthium dippenaarae Lotz, 2007 Cheiracanthium furculatum Karsch, 1879* Cheiracanthium molle L. Koch, 1875 Cheiracanthium vansoni Lawrence, 1936 Cheiramiona krugerensis Lotz, 2002 Cheiramiona paradisus Lotz, 2002 Cheiramiona silvicola (Lawrence, 1938) NEPHILIDAE Nephila fenestrata Thorell, 1859 NESTICIDAE Nesticella benoiti (Hubert, 1970) OONOPIDAE Dysderina speculifera Simon, 1907 Gamasomorpha australis Hewitt, 1915 Opopaea speciosa (Lawrence, 1952) ORSOLOBIDAE Afrilobus australis Griswold & Platnick, 1987 Azanialobus lawrencei Griswold & Platnick, 1987 A.S. Dippenaar-Schoeman et al.: Knowledge of Spider Diversity in Agroecosystems APPENDIX 1 (Continued ) Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 Species OXYOPIDAE Hamataliwa kulczynskii (Lessert, 1915) Oxyopes bothai Lessert, 1915 Oxyopes flavipalpis (Lucas, 1858) Oxyopes hoggi Lessert, 1915 Oxyopes jacksoni Lessert, 1915 Oxyopes longispinosus Lawrence, 1938 Oxyopes pallidecoloratus Strand, 1906 Oxyopes schenkeli Lessert, 1927 Peucetia viridis (Blackwall, 1858) PALPIMANIDAE Diaphorocellus biplagiatus Simon, 1893 Palpimanus transvaalicus Simon, 1893 PHILODROMIDAE Gephyrota sp. Hirriusa arenacea (Lawrence, 1927) Philodromus brachycephalus Lawrence, 1952 Philodromus browningi Lawrence, 1952 Philodromus guineensis Millot, 1942 Philodromus maestrii Caporiacco, 1941 Philodromus thanatellus Strand, 1909 Thanatus dorsilineatus Jezequel, 1964 Thanatus vulgaris Simon, 1870 Tibellus minor Lessert, 1919 PHOLCIDAE Quamtana bonamanzi Huber, 2003 Quamtana ciliata (Lawrence, 1938) Quamtana embuleni Huber, 2003 Quamtana merwei Huber, 2003 Smeringopus natalensis Lawrence, 1947 Smeringopus sambesicus Kraus, 1957 PHYXELIDIDAE Pongolania chrysionaria Griswold, 1990 Vidole capensis (Pocock, 1900) Vidole sothoana Griswold, 1990 Xevioso aululata Griswold, 1990 Xevioso colobata Griswold, 1990 Xevioso kulufa Griswold, 1990 Xevioso tuberculata (Lawrence, 1939) PISAURIDAE Charminus aethiopicus (Caporiacco, 1939) 15 APPENDIX 1 (Continued ) Guild Crops PW avocado, macadamia PW PW cotton, pistachio sugar cane PW PW pistachio citrus, macadamia, maize, sunflower macadamia PW PW PW PW cabbage, citrus, maize, tomatoes avocado, citrus, macadamia pistachio GW pistachio GW citrus, cotton PW GW macadamia, maize, pistachio, sunflower, tomatoes pistachio GW avocado, macadamia PW pecans, pistachio GW avocado, citrus GW mango GW vineyards GW/ PW GW maize PW cotton, lucerne, maize, potatoes, strawberries cotton, maize, vineyards SpWB citrus SpWB citrus, pine plantations SpWB citrus SpWB pine plantations SpWB cotton, pistachio SpWB citrus RWB citrus, maize RWB RWB RWB citrus cotton, maize pine plantations RWB citrus RWB RWB macadamia citrus PW macadamia, maize Species Guild Crops Chiasmopes lineatus (Pocock, 1898) Maypacius curiosus Blandin, 1975 Perenethis simoni (Lessert, 1916) Perenethis symmetrica (Lawrence, 1927) Rothus purpurissatus Simon, 1898 Rothus vittatus Simon, 1898 PRODIDOMIDAE Prodidomus purpurascens Purcell, 1904 Theuma fusca Purcell, 1907 SALTICIDAE Aelurillus sp. Afraflacilla sp. Asemonea maculata Wanless, 1980 Baryphas ahenus Simon, 1902 SWB maize SWB maize SWB citrus SWB maize PWB lucerne, pecans, vineyards PWB pistachio GW cotton GW pistachio GW PW PW cotton macadamia avocado, lemon PW GW citrus, maize, pine plantations, strawberries, tomatoes cotton PW GW avocado, cotton vineyards GW PW maize pine plantations PW pine plantations GW GW pistachio tomatoes PW cotton, kenaf, maize GW apple, citrus, kenaf PW PW avocado, citrus, macadamia lucerne, pine plantations, pistachio cotton, pistachio PW potatoes PW cotton, kenaf, sorghum PW citrus, cotton, kenaf PW lucerne, vineyards PW cotton, pecans, potatoes, tomatoes cotton Bianor albobimaculatus (Lucas, 1846) Brancus bevisi (Lessert, 1925) Cyrba dotata Peckham & Peckham, 1903 Cyrba nigrimana Simon, 1900 Dendryphantes hararensis Wesolowska & Cumming, 2008 Dendryphantes purcelli Peckham & Peckham, 1903 Euophrys sp. Evarcha culicivora Wesolowska & Jackson, 2003 Evarcha dotata (Peckham & Peckham, 1903) Evarcha flagellaris Haddad & Wesolowska, 2011 Goleba puella (Simon, 1885) Heliophanus charlesi Wesolowska, 2003 Heliophanus debilis Simon, 1901 Heliophanus fascinatus Wesolowska, 1986 Heliophanus hastatus Wesolowska, 1986 Heliophanus insperatus Wesolowska, 1986 Heliophanus modicus Peckham & Peckham, 1903 Heliophanus nanus Wesolowska, 2003 Heliophanus orchesta Simon, 1886 Heliophanus pistaciae Wesolowska, 2003* PW PW PW Heliophanus proszynski PW Wesolowska, 2003 Heliophanus trepidus Simon, PW 1910 Hyllus argyrotoxus Simon, 1902 PW Hyllus brevitarsis Simon, 1902 PW cotton, kenaf, pecans, pistachio, potatoes, pumpkin, sugar cane cotton, tomatoes, wheat cotton, pistachio avocado, citrus, cotton, macadamia avocado, lemon, macadamia 16 Transactions of the Royal Society of South Africa Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 APPENDIX 1 (Continued ) APPENDIX 1 (Continued ) Species Guild Crops Species Guild Crops Icius insolidus Wesolowska, 1999 Langona manicata Simon, 1901 Menemerus bifurcus Wesolowska, 1999 Menemerus pilosus Wesolowska, 1999 Myrmarachne ichneumon Simon, 1886 Myrmarachne marshalli Peckham & Peckham, 1903 Myrmarachne solitaria Peckham & Peckham, 1903 Myrmarachne uvira Wanless, 1978 Natta horizontalis Karsch, 1879 Nigorella hirsuta Wesolowska, 2009 Pachyballus castaneus Simon, 1900 Pachyballus sp. Pachyballus transversus Simon, 1900 Parajotus obscurofemoratus Peckham & Peckham, 1903 Pellenes bulawayoensis Wesolowska, 1999 Pellenes geniculatus (Simon, 1868) Phintella aequipes (Peckham & Peckham, 1903) Phlegra certa Wesolowska & Haddad, 2009 Phlegra karoo Wesolowska, 2006 Phlegra nuda Próchiewicz & Heciak, 1994 Phlegra simplex Wesolowska & Russell-Smith, 2000 Portia schultzi Karsch, 1878 Pseudicius africanus Peckham & Peckham, 1903 Rhene machadoi Berland & Millot, 1941 Stenaelurillus cristatus Wesolowska & RussellSmith, 2000 Stenaelurillus guttiger (Simon, 1901) Thyene aperta (Peckham & Peckham, 1903) Thyene bucculenta (Gerstäcker, 1873 Thyene coccineovittata (Simon, 1886) Thyene inflata (Gerstäcker, 1873) Thyene natalii Peckham & Peckham, 1903 Thyene ogdeni Peckham & Peckham, 1903 Thyene semiargentea (Simon, 1884) Thyene thyenoides (Lessert, 1925) Thyenula aurantiaca (Simon, 1902) Thyenula fidelis Wesolowska & Haddad, 2009 Tusitala barbata Peckham & Peckham, 1902 GW pistachio PW avocado, macadamia GW PW cotton, maize cotton PW PW avocado, citrus, macadamia macadamia PW pistachio PW avocado, macadamia PW citrus PW macadamia PW citrus, minneola, pecan PW lucerne PW cotton GW GW pine plantations maize GW GW GW avocado, citrus, mango GW pine plantations PW cotton, pistachio cotton, maize, pecans, strawberries citrus PW PW lucerne, onion minneola TWB avocado, citrus, pistachio PW PW macadamia PW avocado, citrus, macadamia pine plantations GW cotton, kenaf, pecans, potatoes cotton, lucerne, maize Tusitala guineensis Berland & Millot, 1941 Tusitala hirsuta Peckham & Peckham, 1902 Veissella durbani (Peckham & Peckham, 1903) Viciria alba Peckham & Peckham, 1903 Zulunigma incognita (Wesolowska & Haddad, 2009) SCYTODIDAE Scytodes caffra Purcell, 1904 Scytodes elizabethae Purcell, 1904 Scytodes flagellata Purcell, 1904 Scytodes maritima Lawrence, 1938 SEGESTRIIDAE Ariadna spp. SELENOPIDAE Anyphops fitzsimonsi (Lawrence, 1940) Anyphops lawrencei (Roewer, 1951) Anyphops minor (Lawrence, 1940) Anyphops rubicundus (Lawrence, 1940) Selenops radiatus Latreille, 1819 SICARIIDAE Loxosceles spinulosa Purcell, 1904 SPARASSIDAE Olios auricomis (Simon, 1880) Olios sjostedti Lessert, 1921 Olios tuckeri Lawrence, 1927 Palystes superciliosus L. Koch, 1875 Panaretella minor Lawrence, 1952 Palystes ansiedippenaarae Croeser, 1996 Palystes superciliosus L. Koch, 1875 TETRAGNATHIDAE Leucauge decorata (Blackwall, 1864) Leucauge festiva (Blackwall, 1866) Leucauge medjensis Lessert, 1930 Leucauge thomeensis Kraus, 1960 Pachygnatha leleupi Lawrence, 1952 Tetragnatha jaculator Tullgren, 1910 Tetragnatha subsquamata Okuma, 1985 THERAPHOSIDAE Brachionopus tristis Purcell, 1903 THERIDIIDAE Achaearanea sp. Anelosimus nelsoni Agnarsson, 2006 Argyrodes convivans Lawrence, 1937 PW sugar cane PW avocado, macadamia PW potatoes GW cotton PW PW PW PW PW avocado, macadamia macadamia macadamia avocado, cabbage, macadamia citrus PW pine plantations PW pine plantations OWB citrus, maize OWB avocado, macadamia, pumpkin, tomatoes citrus GW PW GW avocado, grapefruit, macadamia cotton GW pecans, pistachio GW cotton GW cotton, maize, tomatoes PW PW macadamia pine plantations PW lucerne GW maize GW cotton PW pistachio PW cotton, lucerne PW PW avocado, citrus, grapefruit, macadamia avocado, citrus, cotton, grapefruit, pistachio avocado, citrus, macadamia, tomatoes citrus PW cotton PW pecans PW avocado, macadamia GW pine plantation PW citrus, pistachio PW PW OWB OWB OWB avocado, citrus, macadamia maize, potatoes OWB cotton, maize OWB avocado, macadamia, maize GW citrus GWB GWB citrus, vineyards citrus GWB citrus, cotton A.S. Dippenaar-Schoeman et al.: Knowledge of Spider Diversity in Agroecosystems APPENDIX 1 (Continued ) APPENDIX 1 (Continued ) Species Guild Crops Species Guild Crops Coleosoma blandum O.P.Cambridge, 1882 Dipoena sp. Dipoenura sp. Enoplognatha molesta O.P.Cambridge, 1904* GWB grapefruit, minneola PW citrus GWB GWB GWB citrus, cotton citrus, tomatoes citrus, cotton, maize, potatoes, sorghum, strawberries, sugarcane, tomatoes vineyards Phrynarachne melloleitaoi Lessert, 1933 Runcinia aethiops (Simon, 1901) Runcinia affinis Simon, 1897 PW pine plantations, strawberries cotton, lucerne, strawberries pistachio, potatoes, sugar cane, strawberries kenaf Euryopis episinoides (Walckenaer, 1847) Euryopis sp. Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 17 Latrodectus cinctus Blackwall, 1865 Latrodectus geometricus C.L. Koch, 1841 Latrodectus indistinctus O.P.Cambridge, 1904 Latrodectus renivulvatus Dahl, 1902 Phoroncidia sp. Steatoda capensis Hann, 1990 Steatoda erigoniformis (O.P.Cambridge, 1872) Steatoda grossa (C.L. Koch, 1838) Theridion pictum (Walckenaer, 1802) Theridion purcelli O.P.Cambridge, 1904 Theridula sp. Tidarren cuneolatum (Tullgren, 1910) THOMISIDAE Ansiea tuckeri (Lessert, 1919) Borboropactus silvicola (Lawrence, 1938) Camaricus nigrotesselatus Simon, 1895 Diaea puncta Karsch, 1884 Firmicus bragantinus (Brito Capello, 1866) Heriaeus transvaalicus Simon, 1895 Misumenops rubrodecoratus Millot, 1941* Monaeses austrinus Simon, 1910 Monaeses fuscus DippenaarSchoeman, 1984 Monaeses quadrituberculatus Lawrence, 1927 Oxytate argenteooculata (Simon, 1886) Oxytate concolor (Caporiacco, 1947) Ozyptila caenosa Jézéquel, 1966 Parasmodix quadrituberculata Jézéquel, 1966 Pherecydes tuberculatus O.P.Cambridge, 1883 GWB GWB GWB GWB GWB GWB cotton, minneola, maize, pear citrus, tomatoes avocado, citrus, cotton, maize, pistachio, prickly pears, vineyards pistachio GWB cotton, maize, strawberries, sugarcane, vineyards citrus, tomatoes maize, pear, tomatoes, pine plantations, vineyards cotton, maize, tomatoes GWB cotton GWB avocado, macadamia GWB citrus, cotton, macadamia, maize, strawberries, sunflower, tomatoes citrus, cotton avocado, citrus, macadamia, pistachio GWB GWB GWB GWB PW PW avocado, macadamia, pine plantations maize PW tomatoes PW avocado, cotton, pistachio, strawberries avocado, citrus, grapefruit PW PW PW avocado, cotton, strawberries avocado, citrus, cotton, kenaf, lucerne, macadamia, maize, pecans, pine plantations, pistachio, pumpkin, sugar cane, sunflower, strawberries, tomatoes cotton, pistachio PW cotton, potatoes PW lucerne, pistachio PW PW avocado, citrus, macadamia, tomatoes avocado, citrus, macadamia maize PW maize PW lucerne, pine plantations PW PW PW Runcinia depressa Simon, PW 1906 Runcinia erythrina Jézéquel, PW 1964 Runcinia flavida (Simon, 1881) PW Runcinia grammica (L. Koch, 1937) Simorcus cotti Lessert, 1936 Sylligma theresa Lewis & Dippenaar-Schoeman, 2011 Synema decens (Karsch, 1878) Synema diana (Audouin, 1826) Synema imitator (Pavesi, 1883) Synema langheldi Dahl, 1907 PW pine plantations, strawberries tomatoes PW PW citrus maize PW PW PW PW tomatoes tomatoes tomatoes citrus, macadamia, minneola citrus Thomisops senegalensis Millot, PW 1941 Thomisus australis Comellini, PW 1957 Thomisus blandus Karsch, PW 1880 Thomisus citrinellus Simon, 1875 Thomisus congoensis Comellini, 1957 Thomisus dalmasi Lessert, 1919 Thomisus daradioides Simon, 1890 Thomisus granulatus Karsch, 1880 Thomisus kalaharinus Lawrence, 1936 Thomisus machadoi Comellini, 1959 Thomisus scrupeus (Simon, 1886) Thomisus stenningi Pocock, 1900 Thomisus unidentatus Dippenaar-Schoeman & Van Harten, 2007 Tmarus cameliformis Millot, 1941 Tmarus comellinii Garcia-Neto, 1989 Tmarus foliatus Lessert, 1928 Tmarus natalensis Lessert, 1925 Xysticus natalensis Lawrence, 1938 Xysticus urbensis Lawrence, 1952 TROCHANTERIIDAE Platyoides walteri (Karsch, 1886) ULOBORIDAE Uloborus plumipes Lucas, 1846 PW peach, pine plantations, tomatoes citrus, cotton, maize, papaya, pumpkin, strawberries pecans PW cotton, minneola PW lucerne, strawberries PW citrus, macadamia PW citrus PW pistachio PW pistachio PW avocado, citrus, cotton, minneola, sunflower cotton, potatoes, lucerne, pecans, pine plantations, pistachio, strawberries, wheat citrus PW PW PW PW avocado, citrus, cotton, macadamia avocado, mango PW PW sugar cane macadamia GW GW avocado, cotton, strawberries, sugar cane maize PW avocado, pine plantations OWB avocado, citrus, cotton, pistachio, prickly pear, strawberries, tomatoes 18 Transactions of the Royal Society of South Africa APPENDIX 1 (Continued ) Downloaded by [ARC Central Office], [Professor A.S. Dippenaar-Schoeman] at 04:25 16 January 2013 Species ZODARIIDAE Cydrela schoemanae Jocqué, 1991 Diores recurvatus Jocqué, 1990 Diores strandi Caporiacco, 1949 Diores triangulifer Simon, 1910 Heradida sp. Microdiores sp. Ranops caprivi Jocqué, 1991 ZOROPSIDAE Phanotea cavata Giswold, 1994 Guild Crops GW maize, pine plantations GW GW cotton maize GW GW GW GW pistachio cotton citrus, maize cotton RWB citrus