Conservation implications: Only a small proportion (ca. 5.5%) of the DAC is conserved, the majority of which lies in the uKhahlamba-Drakensberg Park World Heritage Site. Conservation of more of the DAC, including more of its latitudinal extent, is required to adequately conserve its unique plant and invertebrate communities.

The peaks were chosen for several reasons: their altitude (situated within the alpine zone), the assumed infrequent nature or exclusion of the two major disturbance factors along the Drakensberg escarpment, namely, fire and herbivory by domestic livestock, and the isolation of the peaks, or inselbergs, which can be regarded as an archipelago of ‘islands’, which theoretically could house unique, high-altitude endemics. Fire frequency, extent and intensity, as well as season of burn and time since last burn can influence the composition of invertebrate assemblages at lower altitudes in the uKhahlamba-Drakensberg Park World Heritage Site (Uys 2006; Uys et al. 2006, 2010). Invertebrate diversity is lower in grassland under communal grazing in comparison to grassland under nature conservation in a region south-east of the uKhahlamba-Drakensberg Park World Heritage Site (Robertson & Van Noort 2003; Wildy 2003).

The results of an invertebrate survey carried out between 28 November and 05 December 2005 are presented here. The goal of the invertebrate survey was to sample six out of a possible 11 isolated peaks at altitudes of 3000 m or more in the uKhahlamba-Drakensberg Park World Heritage Site in KwaZulu-Natal. The peaks were chosen to ensure that a sufficient latitudinal and longitudinal range was incorporated by the sampling and that the peaks were large enough to safely land a helicopter and to establish sample plots adequate for invertebrate and vegetation sampling.

• The DAC is a centre of endemism for invertebrates, where a relatively high proportion of invertebrate species are endemic.
• Invertebrate communities change from isolated peak to isolated peak, and possible reasons for this change.

Only adults of each species were included in the analyses because juveniles do not necessarily have the specific diagnostic identification characters. Specimens were identified to species through: (1) reference to identified specimens and sometimes also to unidentified specimens housed in several collections, that is, the KwaZulu-Natal Museum in Pietermaritzburg (NMSA), and the South African National Collection of Insects (SANC) and the Ditsong National Museum of Natural History, formerly the Transvaal Museum (TMSA), in Pretoria, (2) identification keys, published taxonomic papers and a regional fauna guide (Alexander 1964; Brown 1962; Eardley 1988; Eardley, Kuhlmann & Pauly 2010; Fennah 1967; Iwan 2001; Londt 1981; Marshall 1904; Princis 1963; Pringle, Henning & Ball 1994; Slater 1964; Straneo 1958; Synave 1956; Theron 1986; Wittmer 1949) and (3) specialist taxonomists (see Acknowledgements). The distribution ranges and endemicity of the species were ascertained or estimated from specimen label data and distribution records contained in the publications listed above and in the Biodiversity Database of Ezemvelo KZN Wildlife, and from Armstrong et al. (1994), Armstrong and Van Hensbergen (1997a, 1997b, 1999), Arnott (2006), Hamer and Slotow (2007) and Uys et al. (2006, 2010).

FIGURE 1: (a) Map of South Africa showing the extent of the Drakensberg Alpine Centre (grey) and the study region (box). (b) Enlargement of the study region indicating the study sites (dots).

Analysis of the plots by species matrix was carried out using PC-Ord5 (McCune & Mefford 1999). McCune and Grace (2002) and the PC-Ord5 advisor wizard were used to select an appropriate data relativisation method and analysis type. The percentage of cells empty was 74.317%. The co-efficient of variation (CV) of plot totals was 88.48% and the CV of species totals was 240.30%. Species abundances were relativised by maximum to counter the effect that a few species that were relatively abundant at the time of sampling would have on the analysis and because the sampling time was restricted to a short period, which led to most species being rare in the samples. After relativisation, no plots or species were recognised as outliers using the Sorensen (Bray-Curtis) distance measure and a cutoff of two standard deviations from the grand mean. A cluster analysis dendrogramme was produced using the Sorensen (Bray-Curtis) distance measure and the flexible beta (beta set to −0.25) group linkage method. Non-metric multidimensional scaling (NMDS) was carried out using the autopilot mode and the Sorensen (Bray-Curtis) distance measure (McCune & Grace 2002). A random starting configuration and 250 runs with real data and 250 runs with randomised data for comparison were utilised.

• The further away the peaks from the Sentinel in straight-line distance, the greater the turnover of species and therefore the greater the difference in observed species complement.

• Species composition should be more similar between closer peaks than between peaks further apart.

• Peaks further away from the main massif were expected to have depauperate faunas compared to peaks closer to the main massif, owing to stochastic events that may have eliminated certain species that would not have recolonised the peak easily or rapidly from the main massif.

• The larger the area of the peak, the greater the number of species that would be recorded.

• Differences in extreme temperatures (represented by the means of daily minimum temperature for the coldest month, July, and the means of daily maximum temperature for the hottest month, January) or else in mean annual temperature would influence the distribution of species on the peaks (climate data obtained from Schulze 2007).

• Differences in mean annual precipitation between the peaks would cause differences in the faunal communities on the peaks.

• Differences in the altitude of the peaks are small and would not influence the composition of the faunal communities.

The six peaks were grouped into a northern pair (Sentinel and Eastern Buttress), a central pair (Inner and Outer Horns) and a southern pair (Dragon’s Back and Cathkin).

FIGURE 2: Number of species recorded of each endemicity status (not endemic to the Drakensberg Alpine Centre, endemic or probably endemic to the Drakensberg Alpine Centre, and status unknown) in the invertebrate families sampled.

FIGURE 3: (a) Invertebrate sampling on Cathkin Peak. The unique high altitude vegetation is a mix of bunch grasses, Merxmuellera and Pentaschistis, and low cushion shrubs, Erica, Euryops and Helichrysum, habitat for herbivore and detritivore invertebrates. (b) Drakensberg Escarpment, showing the island-like archipelago of inselbergs. Summits in the distance from the right: Inner Tower, Devil’s Tooth and Eastern Buttress; Sentinel in the foreground. (c) The flat surface of Cathkin Peak allows for low terrain heterogeneity, but houses high numbers of endemic invertebrates and plants. (d) The DAC-endemic inflated-front wingless grasshopper, Eremidium inflatifrons (female). (e) Montane tail-wagger snail, Sheldonia fuscicolor, on Cathkin Peak.

FIGURE 4: Cluster analysis dendrogramme showing relationship between peaks in species space.

This study of the plant and invertebrate communities on the inselbergs of the alpine region of the uKhahlamba-Drakensberg Park World Heritage Site appears to be the first of its kind. The conservation context of the study is the planned increase in area under protection in the Maloti Drakensberg Transfrontier Project planning region (Maloti Drakensberg Transfrontier Project 2008).

The number of undescribed species indicates that the invertebrate fauna of the DAC is still not well-described. Certain species, however, do appear to have restricted ranges even within the DAC (Appendix 1). The fact that some endemic microchaetid earthworms and wingless bugs have restricted distribution ranges is well known (Plisko 2003; Stiller 2009, 2010; Theron 1986). These species may only occur on certain peaks as a result of the spatial distribution of the environmental factors that influence the species’ distributions and the relative immobility of the species. These environmental factors may include soil attributes such as pH, depth, and clay and water content, and vegetation attributes such as physiognomy and host-plant distributions (e.g. Edwards & Bohlen 1996 for earthworms). Species associated with grasses (because they or their larvae are grass-feeders or else they are associated with forbs growing in grassland) would be more likely to be found on the peaks with a greater proportion of the area under grasses, these being the Sentinel, Dragon’s Back, and Cathkin (main plant communities one and two comprised of shrubs and grasses). Lepidopteran and hemipteran grass-feeders such as Pseudonympha gaika, Pravistylus interdiscus, and Drakensbergena bisulca (Pringle et al. 1994; Stiller 2009, 2010), and an orthopteran that feeds on leaves of bushes or forbs in grassland, Basutacris inflatifrons (Brown 1962; Figure 3d), tend to show this type of distribution (Appendix 1). Other possibilities are that specific plant species with which certain wingless species are associated may not occur on some inselbergs, or finally, some wingless species may not be present on certain peaks because they have become extinct on those peaks through the impact of environmental stochasticity.

The most important factors influencing invertebrate community composition on the inselbergs was distance from the Sentinel and mean minimum temperature for July, according to the NMDS analysis (Table 4). Distance from the Sentinel reflects how much further away in a south-easterly direction the next peak is from the Sentinel (Figure 1b). Turnover of species in this south-easterly direction is reflected. That the two northern peaks clustered together, the most southerly peak, Cathkin, formed its own cluster, and the other three peaks formed a cluster according to the cluster analysis (Figure 4) gives support to this contention. Mean annual rainfall tends to increase in this direction, as do the maximum and minimum temperature figures to a lesser extent (Table 1). Change in species identities and taxon richness occurs with increasing altitude in the Drakensberg mountains and, at least for some taxa, fewer species are encountered at higher altitudes (e.g. Armstrong & Van Hensbergen 1997a, 1997b; Samways 1989; Stuckenberg 1962). Pryke and Samways (2008, 2010) found that invertebrate species richness, abundance and composition changed with altitude on Table Mountain. Epigaeic and aerial invertebrates decreased in richness and abundance with increasing altitude but the converse was true for foliage invertebrates. Therefore, beta diversity might be expected to be lower at higher altitudes in the DAC. Only one species was recorded in all three clusters (Figure 4; Appendix 1). More intensive sampling may reveal that other species occur in all the clusters. Uys et al. (2009) determined high turnover values for flightless forest invertebrates at scales varying from a few hundred metres to tens of kilometres at lower altitudes in the same general region of the uKhahlamba-Drakensberg Park World Heritage Site as this study.

Mean minimum temperature for July (the coldest month) was found to influence invertebrate community composition. The temperature data were at a one minute by one minute scale that was possibly too large to give precise temperatures for each peak. The South African Weather Service has 17 stations in the Drakensberg, of which two, Sani Pass (2865 m) and Witsieshoek (2500 m, below the Sentinel), are at high altitude, yet still below the altitudes of the study sites (Nel 2007). The influence of low temperatures, frost, and low oxygen partial pressure on insects has been documented (Chapman 2002), and these play an appreciable part as limiting factors responsible for insect endemism and diversity at high altitude. Altitude and vegetation structure are two of the most important environmental variables that influence invertebrate diversity on Table Mountain (Pryke & Samways 2008, 2010). The texture and structure of Alpine vegetation, regardless of slope, aspect and soils, is dependent on the maximum and minimum temperatures (Körner 2003), which might thus influence the relationship between invertebrates and vegetation type.

Insects and other invertebrates, like lizards, are poikilotherms; their temperature depends largely on the amount of incident solar radiation and on the ambient temperature (Chapman 2002; Clusella-Trullas et al. 2008). Clusella-Trullas et al. (2008) found that skin reflectance was more strongly related to mean annual radiation than to mean annual temperature in their sample of 68 and 66 species of lizards, respectively. Dark beetles absorb more direct shortwave and visible radiation than light-coloured ones, which would enable them to use more limited amounts of sunlight to warm up and become active, providing wind is absent (e.g. Turner & Lombard 1990). Alpine and arctic insects are often dark, or have darker scales and wing undersides to take advantage of low ambient light and temperature levels (Chapman 2002). About 60% of the insect species sampled during the present study are black or very dark brown or grey, and may be darker than congeners at lower altitudes. The montane tail-wagger snail Sheldonia fuscicolor (Figure 3e), for example, is darker than its congeners at lower altitudes in KZN (Herbert & Kilburn 2004).

Insect taxa that have species known to be frost tolerant include Blattoidea, Hemiptera, Diptera, Lepidoptera, Coleoptera and Hymenoptera (Chapman 2002; cf. Appendix 1). Insects living in the DAC have to endure temperatures close to and below freezing at various times of the year, and especially in winter, and so are likely to be freeze tolerant (Sinclair & Chown 2005). Two species from the KZN part of the DAC, a cockroach (probably Perisphaeria guillarmodi; S. van Noort, pers. comm., 23 April 2012) and a ground beetle, were included in the study of Sinclair and Chown (2005). Both these species are moderately freeze-tolerant, with a lethal temperature lower than the temperature of crystallisation. The low temperature at which 50% mortality (LT₅₀) of the cockroach was recorded was −9.7 ºC and the LT₅₀ for the ground beetle was −4.4 ºC (Sinclair & Chown 2005). Therefore, many of the species recorded are likely to be adapted to the low solar radiation incidence and ambient temperatures experienced during the winter season and the frequently cloudy and wet summer period in the DAC (Killick 1978). The ability to endure low solar radiation and temperatures is likely a major factor that influences the composition of invertebrate communities in the DAC.

Expectations one, two, five and seven were the only ones supported or partially supported by the data (see Research methods and design: Statistical analysis; Figure 4; Tables 1, 2 & 4). Surface area of the inselbergs was not important in terms of structuring the invertebrate communities nor in terms of the number of species present (Tables 1 & 4). The Eastern Buttress yielded only four species from the focal groups, even though it was the second-largest peak, possibly as a result of the cool and damp conditions following the storm the evening before sampling, which may have inhibited some invertebrate activity and therefore detection of certain species. The Outer Horn and the Inner Horn were expected to have the most similar faunal community in terms of invertebrate species identities, because they were the pair of peaks closest together (Table 1). They shared seven species (as recorded during the plot counts), and this pair of peaks was ranked second in number of shared species.

One of the more important factors allowing for high biodiversity is terrain heterogeneity (Cowling & Lombard 2002), that is, mountains tend to be topographically complex with variations of soil, rocky slopes, and aspect and have more species than flat areas due to the greater number of ecological niches available. The relatively flat topography on the inselbergs (Figure 3b & 3c) does not allow for significant habitat differentiation and only four main vegetation communities (habitats) are found. Despite this, of the total 61 invertebrate taxa found, 11 are DAC endemics, with a further 11 possibly endemic to the DAC (Figure 2). This represents 36.1% endemic and possibly endemic species out of the total fauna sampled and is comparable with that found in a study of invertebrates on Table Mountain, Cape Town, where habitat heterogeneity was higher (total of 175 species, with 6 surface-endemic invertebrate species and 28 Cape Peninsula endemics, giving 16% endemicity; Pryke & Samways 2008, 2010). Endemicity varied from 0% to 100% amongst the various families recorded in the present study (Figure 2). Picker and Samways (1996) recorded percentage endemicity of between 5% and 67% for various faunal taxa on the Cape Peninsula in a far more comprehensive study.

The results of the present study suggest that the focal invertebrate taxa for sampling should be groups with range-restricted DAC-endemic species, such as (other reasons in parentheses): earthworms (detritivores and soil engineers that are likely to be sensitive to soil water changes caused by trampling and excessive removal of vegetation and plant litter), wingless grasshoppers (herbivores that may be sensitive to changes in vegetation structure and composition), flightless bugs (herbivores that are likely to be sensitive to vegetation changes caused by excessive fire and livestock herbivory), crane flies (detritivores that are likely to be sensitive to changes in vegetation and surface water), ground beetles (predators of other invertebrates), darkling beetles (detritivores) and hair beetles (decomposers of vertebrate remains that may be sensitive to changes in abundance of mammals and birds caused by hunting pressure and changes in vegetation structure caused by altered fire and herbivory regimes). A relatively large proportion of insect species inhabiting high-altitude areas are wingless (e.g. Endrődy-Younga 1989; Roff 1990). These insects are most likely to be vulnerable to large-scale changes in vegetation as their mobility is reduced compared to fully-winged species. The sampling methods used would have to be appropriate to these groups and the sampling would have to be intensive enough to discern changes in the abundance and identities of species occurring in the treatment area relative to the control.

The precise relationship between plant community structure and alpine invertebrate use of, dependence on, and insect pollination of plants is not clear from this survey and requires further investigation. A vegetation-based approach to insect conservation may be fruitful (e.g. Panzer & Schwartz 1998).

Armstrong, A.J. & Van Hensbergen, H.J., 1997a, ‘Evaluation of afforestable montane grasslands for wildlife conservation in the north-eastern Cape, South Africa’, Biological Conservation 81, 179–190. PMid:17538161

Armstrong, A.J. & Van Hensbergen, H.J., 1997b, ‘A test of the applicability of a wildlife conservation evaluation method to an afforestable region of Mpumalanga’, South African Journal of Wildlife Research 27, 73–77. PMid:17960012

Armstrong, A.J. & Van Hensbergen, H.J., 1999, ‘Identification of priority regions for animal conservation in afforestable montane grasslands of the northern Eastern Cape Province, South Africa’, Biological Conservation 87, 93–103. PMid:18784101

Armstrong, A.J., Van Hensbergen, H.J. & Geertsema, H., 1994, ‘Evaluation of afforestable montane grasslands for wildlife conservation in the north-eastern Cape, South Africa. Part 1. Methods’, South African Forestry Journal 171, 7–20. PMid:19197326

Arnott, W.L., 2006, ‘The effect of burning frequency on invertebrate and indigenous flowering forb diversity in a Drakensberg grassland ecosystem’, MSc thesis, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Pietermaritzburg.

Bazelet, C.S. & Samways, M.J., 2011, ‘Relative importance of management vs. design for implementation of large-scale ecological networks’, Landscape Ecology 26, 341–353.

Brand, R.F., 2006, ‘The ecology and biogeography of pre and post Gondwana inselbergs, Drakensberg Alpine Centre, South Africa’, Report to the National Geographic Society, Committee for Science and Exploration, Washington, DC.

Brand, R.F., submitted, ‘A floristic, biogeographic and growth form assessment of Afroalpine inselberg vegetation in the Drakensberg Alpine Centre’, South African Journal of Botany. PMid:8136946

Brand, R.F., Collins, N. & Du Preez, P.J., in prep., ‘A phytosociology survey and biogeographical description of inselberg vegetation in the Drakensberg Alpine Centre, South Africa’.

Brown, H.D., 1962, ‘New and interesting grasshoppers from southern Africa – 3 (Othoptera: Acridoidea)’, Journal of the Entomological Society of South Africa 25, 198–229.

Carbutt, C. & Edwards, T.J., 2004, ‘The flora of the Drakensberg Alpine Centre’, Edinburgh Journal of Botany 60, 581–607.

Carbutt, C. & Edwards, T.J., 2006, ‘The endemic and near-endemic angiosperms of the Drakensberg Alpine Centre’, South African Journal of Botany 72, 105–132.

Chapman, R.F., 2002, ‘Thermal relations’, in R.F. Chapman (ed.), The insects: Structure and function, pp. 509–530, Cambridge University Press, Cambridge.

Clark, V.R., Barker, N.P. & Mucina, L., 2011, ‘The great escarpment of southern Africa: A new frontier for biodiversity exploration’, Biodiversity and Conservation 20, 2543–2561.

Clusella-Trullas, S., Terblanche, J.S., Blackburn, T.M. & Chown, S.L., 2008, ‘Testing the thermal melanism hypothesis: A macrophysiological approach’, Functional Ecology 22, 232–238.

Colwell, R.K., 2005, EstimateS: Statistical estimation of species richness and shared species from samples, Version 7.5, User’s Guide and application published, viewed 11 June 2012, from http://purl.oclc.org/estimates

Cowling, R.M. & Lombard, A.T., 2002, ‘Heterogeneity, speciation/extinction history and climate: Explaining regional plant diversity patterns in the Cape Floristic Region’, Diversity and Distributions 8, 163–179.

Eardley, C.D., 1988, ‘A revision of the genus Lithurge Latreille (Hymenoptera: Megachilidae) of sub-Saharan Africa’, Journal of the Entomological Society of South Africa 51, 251–263.

Eardley, C., Kuhlmann, M. & Pauly, A., 2010, ‘The bee genera and subgenera of sub-Saharan Africa’, Abc Taxa 7, 1–139.

Edwards, C.A. & Bohlen, P.J., 1996, Biology and ecology of earthworms, Chapman & Hall, London.

Endrődy-Younga, S., 1989, ‘The evolution of alternative life styles in Coleoptera’, in M.N. Bruton (ed.), Alternative life-history styles of animals, pp. 317–327, Kluwer Academic Publishers, Dordrecht.

Fennah, R.G., 1967, ‘New and little-known Fulgoroidea from South Africa (Homoptera)’, Annals of the Natal Museum 18, 655–714.

Gröger, A. & Barthlott, W., 1996, ‘Biogeography and diversity of the inselbergs (Laja) vegetation of southern Venezuela’, Biodiversity Letters 3, 165–179.

Hamer, M. & Slotow, R., 2007, ‘An assessment and ecological interpretation of the terrestrial invertebrate fauna of the South African portion of the Maloti-Drakensberg bioregion’, Unpublished Report to the Maloti-Drakensberg Transfrontier Park project, Inland Invertebrate Initiative, University of KwaZulu-Natal, Pietermaritzburg.

Herbert, D. & Kilburn, D., 2004, Field guide to the land snails and slugs of eastern South Africa, Natal Museum, Pietermaritzburg.

Iwan, D., 2001, ‘Two new species of Bantodemus Koch, 1955 (Coleoptera: Tenebrionidae: Platynotini) from South Africa’, Annales Zoologici (Warszawa) 51, 505–510.

Killick, D.J.B., 1978, ‘The Afro-alpine Region’, in M.J.A. Werger (ed.), Biogeography and ecology of southern Africa, pp. 515–560, Junk, The Hague.

Killick, D.J.B., 1990, A field guide to the flora of the Natal Drakensberg, Jonathan Ball and Ad. Donker, Johannesburg.

King, L.C., 1963, South African scenery: A textbook of geomorphology, Oliver and Boyd, Edinburgh.

Körner, C., 2003, Alpine plant life: Functional plant ecology of high mountain ecosystems, Springer-Verlag, Berlin.

Londt, J.G.H., 1981, ‘Afrotropical Asilidae (Diptera) 5: The genus Dasophrys Loew, 1858 (= Hobbyus Bromley, 1952) (Asilinae: Asilini)’, Annals of the Natal Museum 24, 635–699.

Lovell, S.J., Hamer, M.L., Slotow, R.H. & Herbert, D., 2010, ‘Assessment of sampling approaches for a multi-taxa invertebrate survey in a South African savanna-mosaic ecosystem’, Austral Ecology 35, 357–370.

Maloti Drakensberg Transfrontier Project, 2008, ‘Conservation and development strategy (2008–2028) for the Maloti Drakensberg Transfrontier Conservation Area’, Maloti Drakensberg Transfrontier Project South Africa, Howick.

Marshall, G.A.K., 1904, ‘A monograph on the Coleoptera of the genus Hipporrhinus, Schh. (Curculionidae)’, Proceedings of the Zoological Society of London, 6–141.

McCune, B. & Grace, J.B., 2002, Analysis of ecological communities, MjM Software Design, Gleneden Beach, Oregon.

McCune, B. & Mefford, M.J., 1999, PC-ORD: Multivariate analysis of ecological data, Version 4, MjM Software Design, Gleneden Beach, Oregon.

Nel, W., 2007, ‘On the climate of the Drakensburg: Rainfall and surface-temperature attributes, and associated geomorphic effects’, PhD dissertation, Department of Geography, Geo-Informatics and Meteorology, University of Pretoria, Pretoria.

Panzer, R. & Schwartz, M.W., 1998, ‘Effectiveness of a vegetation-based approach to insect conservation’, Conservation Biology 12, 693–702.

Parmentier, I., Oumorou, M., Porembski, S., Lejoly, J. & Decocq, G., 2006, ‘Ecology, distribution, and classification of xeric monocotyledonous mats on inselbergs in West Africa and Atlantic central Africa’, Phytocoenology 36, 547–564.

Picker, M.D. & Samways, M.J., 1996, ‘Faunal diversity and endemicity of the Cape Peninsula, South Africa – A first assessment’, Biodiversity and Conservation 5, 591–606.

Plisko, J.D., 1994, ‘New and little-known species of Proandricus Plisko, 1992 from Lesotho and Transkei (southern Africa) (Oligochaeta: Microchaetidae)’, Annals of the Natal Museum 35, 229–235.

Plisko, J.D., 2003, ‘Eleven new South African earthworms (Oligochaeta: Microchaetidae) with new information on some known species, and an inventory of the microchaetids of KwaZulu-Natal’, African Invertebrates 44, 279–325.

Porembski, S., Szarzynske, J., Mund, J-P. & Barthlott, W., 1996, ‘Biodiversity and vegetation of small-size inselbergs in a West African rain forest (Taï, Ivory Coast)’, Journal of Biogeography 23, 47–55.

Princis, K., 1963, ‘Blattariae’, in B. Hanstrom, P. Brinck & G. Rudebeck (eds.), South African animal life, vol. 9, pp. 9–318, Swedish Natural Science Research Council, Stockholm.

Pringle, E.L.L, Henning, G.A. & Ball, J.B. (eds.), 1994, Pennington’s butterflies of southern Africa, Struik, Cape Town.

Pryke, J.S. & Samways, M.J., 2008, ‘Conservation of invertebrate biodiversity on a mountain in a global biodiversity hotspot, Cape Floral Region’, Biodiversity and Conservation 17, 3027–3043.

Pryke, J.S. & Samways, M.J., 2010, ‘Significant variables for the conservation of mountain invertebrates’, Journal of Insect Conservation 14, 247−256.

Pryke, J.S. & Samways, M.J., 2012, ‘Ecological networks act as extensions of protected areas for arthropod biodiversity conservation’, Journal of Applied Ecology 49, 591−600.

Pryke, S.R. & Samways, M.J., 2001, ‘Width of grassland linkages for the conservation of butterflies in South African afforested areas’, Biological Conservation 101, 85–96.

Pryke, S.R. & Samways, M.J., 2003, ‘Quality of remnant indigenous grassland linkages for adult butterflies (Lepidoptera) in an afforested African landscape’, Biodiversity and Conservation 12, 1985–2004.

Robertson, H.G. & Van Noort, S., 2003, ‘Effects of agricultural practices on ants and other Hymenoptera in four farming areas of South Africa’, Unpublished Conservation Farming Project Report to the National Botanical Institute, Pretoria.

Roff, D.A., 1990, ‘The evolution of flightlessness in insects’, Ecological Monographs 60, 389–421.

Samways, M.J., 1989, ‘Taxon turnover in Odonata across a 3000 m altitudinal gradient in southern Africa’, Odonatologica 18, 263–274.

Schulze, R.E. (ed.), 2007, ‘South African atlas of climatology and agrohydrology’, WRC Report 1489/1/06, Water Research Commission, Pretoria.

Sinclair, B.J. & Chown, S.L., 2005, ‘Climatic variability and hemispheric differences in insect cold tolerance: Support from southern Africa’, Functional Ecology 19, 214–221.

Slater, J.A., 1964, ‘Hemiptera (Heteroptera). Lygaeidae’, in B. Hanstrom, P. Brinck & G. Rudebeck (eds.), South African animal life, vol. 10, pp. 15–228, Swedish Natural Science Research Council, Stockholm.

Stiller, M., 2009, ‘A revision of the South African leafhopper genus Drakensbergena Linnavuori (Hemiptera: Cicadellidae: Drakensbergeninae)’, Zootaxa 2132, 1–39.

Stiller, M., 2010, ‘Revision of the southern African leafhopper genus Pravistylus (Hemiptera: Cicadellidae: Deltocephalinae)’, Zootaxa 2468, 1–81.

Straneo, S.L., 1958, ‘Carabidae Pterostichinae’, in B. Hanstrom, P. Brinck & G. Rudebeck (eds.), South African animal life, vol. 5, pp. 9–318, Swedish Natural Science Research Council, Stockholm.

Stuckenberg, B.R., 1962, ‘The distribution of the montane palaeogenic element in the South African invertebrate fauna’, Annals of the Cape Provincial Museums 2, 190–205.

Synave, H., 1956, ‘Contribution a l’étude des Issidae Africains (Homoptera – Fulgoroidea)’, Bulletin de Institute royal des Sciences naturelles de Belgique 32, 1–22.

Theron, J.G., 1986, ‘New genera and species of southern African Coelidiinae (Homoptera: Cicadellidae), with description of the new Tribe Equeefini’, Phytophylactica 18, 153–163.

Tiner, R.W., 1999, Wetland indicators: A guide to wetland identification, delineation, classification and mapping, Lewis Publishers, Washington, D.C.

Turner, J.S. & Lombard, A.T., 1990, ‘Body color and body temperature in white and black Namib desert beetles’, Journal of Arid Environments 19, 303–315.

Uys, R., 2006, ‘Fire effects on the fauna and flora of the Maloti-Drakensberg bioregion: A review’, Unpublished report, Maloti-Drakensberg Transfrontier Project, Ezemvelo KZN Wildlife, Pietermaritzburg.

Uys, C., Hamer, M. & Slotow, R., 2006, ‘Effect of burn area on invertebrate recolonization in grasslands in the Drakensberg, South Africa’, African Zoology 41, 51–65.

Uys, C., Hamer, M. & Slotow, R., 2009, ‘Turnover in flightless invertebrate species composition over different spatial scales in Afrotemperate forest in the Drakensberg, South Africa’, African Journal of Ecology 47, 341–351.

Uys, C., Hamer, M. & Slotow, R., 2010, ‘Step process for selecting and testing surrogates and indicators of Afrotemperate forest invertebrate diversity’, PLoS ONE 5(2), e9100. PMid:20161757

Van Wyk, A.E. & Smith G.F., 2001, Regions of floristic endemism in southern Africa: A review with emphasis on succulents, Umdaus Press, Hatfield.

Wildy, E.J., 2003, ‘Effect of different land use practices on invertebrate diversity in Underberg (KwaZulu-Natal, South Africa)’, Unpublished Conservation Farming Project Report to the National Botanical Institute, Pretoria.

Wittmer, Von W., 1949, ‘Neue Malacodermata aus der Sammlung des British Museum, London (2. Beitrag zur Kenntnis der Malacodermata Afrikas)’, Annals and Magazine of Natural History Series 12 2, 746–764.