Succulent Karoo Biome Research Articles

<p><strong>Notes on the phytogeography and conservation status of the genus <em>Acanthopsis</em> (Acantheae, Acanthaceae)</strong></p>

Acanthopsis is a genus endemic to southern Namibia and southwestern South Africa. Until recently the taxonomy of the group was poorly understood. As a result of a new taxonomic framework (recognising 20 species), the risk of extinction of each taxon could be reassessed and updated. This contribution presents an overview of the distribution and conservation status of the species, as well as the patterns and possible processes involved in the phytogeography of the genus. Specimen localities for all examined specimens were georeferenced and these values were used for mapping and conservation assessments. Phylogenetic relationships within Acanthopsis were studied by using sequence data from the following six gene regions: nrITS, matK, rbcL, rps16, rpl32-trnL and trnS-trnG-trnG. The group appears to have diversified in the arid mountainous semi-desert of the Richtersveld, Northern Cape, South Africa, with the vast majority (96%) of Acanthopsis taxa endemic or near-endemic to the Succulent Karoo Region (more or less congruent with the Succulent Karoo Biome). Twenty of the 23 taxa are range-restricted and have an Extent of Occurrence ≤10000 km2, with at least eight of these known from only one or two subpopulations each. Fourteen (61%) of the taxa are Red Listed as Least Concern, while 39% are Red Listed as Threatened (Vulnerable, Endangered and Critically Endangered)—mainly as a result of habitat loss due to overgrazing and trampling by domestic livestock. Although the distribution ranges of most members of Acanthopsis coincide with protected areas, the effectiveness of conservation in these regions is questionable as some protected areas are prone to overgrazing and trampling by domestic livestock. The lack of phylogenetic resolution, complex taxonomy and the high numbers of range-restricted and habitat-specific species implies recent speciation in Acanthopsis due to topography, ecological gradients and climatic conditions prevailing in the arid northwestern parts of South Africa’s Northern Cape and adjacent arid parts of southern Namibia.

Both Alpha- and Beta-Rhizobia Occupy the Root Nodules of Vachellia karroo in South Africa.

Vachellia karroo (formerly Acacia karroo) is a wide-spread legume species indigenous to southern Africa. Little is known regarding the identity or diversity of rhizobia that associate with this plant in its native range in South Africa. The aims of this study were therefore: (i) to gather a collection of rhizobia associated with V. karroo from a wide range of geographic locations and biomes; (ii) to identify the isolates and infer their evolutionary relationships with known rhizobia; (iii) to confirm their nodulation abilities by using them in inoculation assays to induce nodules under glasshouse conditions. To achieve these aims, soil samples were collected from 28 locations in seven biomes throughout South Africa, which were then used to grow V. karroo seedlings under nitrogen-free conditions. The resulting 88 bacterial isolates were identified to genus-level using 16S rRNA sequence analysis and to putative species-level using recA-based phylogenetic analyses. Our results showed that the rhizobial isolates represented members of several genera of Alphaproteobacteria (Bradyrhizobium, Ensifer, Mesorhizobium, and Rhizobium), as well as Paraburkholderia from the Betaproteobacteria. Our study therefore greatly increases the known number of Paraburkholderia isolates which can associate with this southern African mimosoid host. We also show for the first time that members of this genus can associate with legumes, not only in the Fynbos biome, but also in the Albany Thicket and Succulent Karoo biomes. Twenty-six putative species were delineated among the 88 isolates, many of which appeared to be new to Science with other likely being conspecific or closely related to E. alkalisoli, M. abyssinicae, M. shonense, and P. tropica. We encountered only a single isolate of Bradyrhizobium, which is in contrast to the dominant association of this genus with Australian Acacia. V. karroo also associates with diverse genera in the Grassland biome where it is quite invasive and involved in bush encroachment. Our findings therefore suggest that V. karroo is a promiscuous host capable of forming effective nodules with both alpha- and beta-rhizobia, which could be a driving force behind the ecological success of this tree species.

Description of a new species of Rhinocoeta Burmeister, 1842 (Scarabaeidae, Cetoniinae) from the South African Northern Cape.

Rhinocoetanamaquasp. nov. is recognised as a separate species from its closest relative, R.cornuta (Fabricius, 1781) after a review and close analysis of specimens recently collected in the semiarid region of the Northern Cape Province, South Africa. The new species can be readily separated from R.cornuta by the drastically reduced tubercle and associated depression on its anterior pronotal margin, particularly in the male. In addition, the general body shape of R.namaqua is more globose than that of R.cornuta, its average total length is larger, and its elytral costae are generally reduced and poorly visible, particularly at the level of the umbones. These characteristics make it practically impossible to separate the two sexes of R.namaqua, without inspection of the internal reproductive organs, as their external morphologies are virtually identical, unlike in R.cornuta. Finally, the aedeagal parameres of R.namaqua exhibit a narrower apex than those of R.cornuta and, in particular, lack the subapical hook-shaped lateral expansions that are so typical of all the other Rhinocoeta s. str. species. The new species appears to be restricted to specific bioregions of the Succulent and Nama Karoo biomes of the Northern Cape, and like all other species of the genus is generally found on or under mammal herbivore dung. Adult activity is limited to short periods immediately after rainfall events, during which individuals fly around and mate, but do not feed on either fruits or flowers.

Diet selection and preference of small ruminants during drought conditions in a dryland pastoral system in South Africa

Semi-arid to arid areas are prone to droughts which are frequent occurrences in South Africa’s rangelands. Drought can trigger plant species compositional changes in rangelands thus influencing the availability and quality of forage for livestock. The availability and quality of forage drives livestock production, especially among pastoralists who mainly rely on the natural rangeland to sustain their livestock and livelihoods. The aim of this study was to determine the forage selection of cross-bred sheep, Swakara sheep (Ovis aries) and Boer goats (Capra hircus), during the wet season in the summer rainfall Nama Karoo and winter rainfall Succulent Karoo biomes in Namaqualand, South Africa. Since this dryland pastoral system was experiencing drought conditions during the study period of 2016 & 2017, the focus of the study was placed within this context to determine, (1) the availability of forage for small ruminants, (2) the nature of diet selection of different small ruminant groups and how it vary between the two biomes, and (3) the role livestock species, breeds and season play in forage preferences. We established diet selection, preference and dietary overlap by using direct observation of livestock grazing in the veld. Results indicate that availability of forage influence diet selection and preferences of all small ruminant groups. There was a high dietary overlap between mixed bred and Swakara sheep irrespective of the biomes. During 2016 annual herbs made up a large proportion of the sheep’s diets indicating an overdependence to this forage resource when it became available in the rangeland. However, due to the drought spell extending into 2017, annual herbs became less available and therefore altered the forage choices of both sheep groups. Goats were primarily browsers in the Succulent Karoo biome where shrubs dominate, but were considered grazers in the Nama Karoo biome where grasses were dominant. Moreover, all small ruminant groups in this study showed non-selective grazing tendencies which is an important grazing management tool to ensure that rangeland resources are not over exploited. We conclude by arguing that the mixture of different livestock species by pastoralists is an effective diversification strategy for better use of rangelands with herbaceous and woody plants during drought periods.

Useful plants of Namaqualand, South Africa: A checklist and analysis

A comprehensive checklist of 2902 vascular plant species for Namaqualand (Western and Northern Cape Provinces of South Africa) is presented, in which the local traditional and contemporary human uses of 384 taxa are indicated. Information was obtained through a literature study and extensive field survey work, including rigorous and detailed interviews and field walks. Of the total of 383 useful plant species, 240 are used in traditional medicine, 185 are edible, and 216 are used in crafts and other miscellaneous uses. Several species are used in more than one of the three main use categories. A total of 119 vascular plant families is represented in Namaqualand, of which 78 include species that are used locally for medicine, food and crafts. Species from 66 families are used for medicinal purposes, 53 include edible species and 57 include species used for crafts and other miscellaneous uses. The families that contribute the highest numbers of useful plant species are Asteraceae (51 spp.), Geraniaceae (23 spp.), Aizoaceae (22 spp.), Apocynaceae (18 spp.), Iridaceae (17 spp.), Asphodelaceae (13 spp.), Fabaceae (13 spp.), Lamiaceae (11 spp.), Apiaceae (10 spp.) and Amaryllidaceae (9 spp.). There are 45 new species-records of plants with human uses and 147 newly reported uses (38 medicinal, 51 edible and 58 crafts and miscellaneous uses). The checklist was used for a regression analysis of the total number of available plant species per family (as independent variable) and the total number of species per family that are used in Namaqualand (as dependent variable). Residual values of predicted vs actual numbers of species show an over-representation of especially Asteraceae (+21), Geraniaceae (+16) and Apocynaceae (+11) and an under-representation of Aizoaceae (−17), Hyacinthaceae (−7) and Poaceae (−6). The inventory data and results are not only of importance in understanding the broader plant use patterns of the Khoi-San legacy in the Succulent Karoo Biome, but also contribute to the conservation of the cultural heritage of the people of Namaqualand, and as a source of ethnobotanical data for future research and comparative analyses.

Inselbergs persist as islands of diversity in a heavily grazed rangeland mosaic at the nexus of three arid biomes

Inselbergs are regarded as ‘islands of diversity’ due to the high number of plant species present and level of endemism. They also act as natural sources of fodder for livestock and thus risk becoming homogenised in a heavily grazed rangeland. The aim of this study was to compare plant diversity on inselbergs and matrices in heavily grazed sections of three arid biomes of South Africa’s west. The inselbergs are scattered in a matrix of rangeland vegetation in the Desert, Nama-Karoo and Succulent Karoo biomes where pastoral herding is the main land use. Plant composition, cover and growth forms were quantified in plots and along transects in 21 inselberg and matrix sites. Inselbergs had more diverse plant and growth forms and greater cover than adjacent matrices. Defoliated plants on inselbergs are able to recover due to more mesic conditions and because inselbergs are largely grazed during drier periods, species are able to flower and set seed during winter. Inselbergs are also less accessible to livestock due to their unique geomorphology. Therefore, inselbergs are able to persist as islands of diversity and warrant inclusion into conservation and rangeland farming management plans since climate change will result in biome boundary shifts.

Plastome based phylogenetics and younger crown node age in Pelargonium

The predominantly South-African plant genus Pelargonium L’Hér. (Geraniaceae) displays remarkable morphological diversity, several basic chromosome numbers as well as high levels of organelle genomic rearrangements, and represents the 7th largest Cape Floristic Region clade. In this study, we reconstructed a phylogenetic tree based on 74 plastome exons and nuclear rDNA ITS regions for 120 species, which represents 43% taxon coverage for Pelargonium. We also performed a dating analysis to examine the timing of the major radiations in the genus.Phylogenetic analyses of nucleotide, amino acid, and ITS alignments confirmed the previously-documented subgeneric split into five main clades ((C1,C2),(B(A1,A2))) although clade only A1 received low bootstrap support.Using calibration evidence from a range of sources the Pelargonium crown age was estimated to be 9.7 My old, much younger than previous estimates for the genus but similar to recent studies of other Cape Floristic lineages that are part of both Fynbos and Succulent Karoo biomes.

Field surveys and revegetation experiments show that simulation of topographical habitat features could improve the chances of successful restoration for the threatened succulent Juttadinteria albata

Species with highly restricted ranges are disproportionately at risk of extinction, particularly where habitat loss occurs as a result of mining. Postmining restoration of rare species populations is considered as an appropriate response to counter such threats, but requires a careful, evidence‐based, and information‐driven approach. The economically important diamond mining at Sendelingsdrif in the southern Namib Desert occurs in the highly diverse Succulent Karoo Biome and threatens a significant part of the population of the narrow endemic succulent plant species Juttadinteria albata. To decrease the inherent risks of restoring such a rare species, we studied the habitat features of premining J. albata populations and experimentally tested whether some features could assist future reintroductions in postmining substrates. Plots where J. albata occurred were mostly south‐ to west‐facing and had among others higher rock cover and steeper slopes than plots where J. albata plants were absent. A revegetation experiment, with J. albata cuttings that were established on postmining substrate mounds, revealed that plants on steeper slopes, facing south to west, grew faster than plants on other slopes and aspects. Slope and aspect are therefore important habitat properties to recreate when restoring J. albata populations. These, and other preferred habitat properties such as higher levels of organic C, should now be tested in larger‐scale field trials. Validation of habitat requirements of J. albata through the revegetation experiment has decreased the risks at least partially and provides additional empirical evidence of the importance of establishing reference conditions to enhance ecological restoration.

Potential insect vectors and alternative host plants of phytoplasmas inthe Fynbos and Succulent Karoo biomes in South Africa

Potential insect vectors and alternative host plants of phytoplasmas inthe Fynbos and Succulent Karoo biomes in South Africa

Rethinking catastrophe? Historical trajectories and modelled future vegetation change in southern Africa

Abstract Most projections of climate change for southern Africa describe a hotter and drier future with catastrophic consequences for the environment and socio-ecological sustainability of the region. This study investigated whether evidence of the projections for the climate and vegetation of the subcontinent is already evident. Analysis of the climate record indicate that the historical trend of increasing temperature is consistent with future projections for the region. Rainfall, however, apparently has not changed significantly. Results from analysis of 1321 repeat historical photographs indicate broad trends in vegetation trajectories in the major biomes of southern Africa. The Savanna biome has experienced a rapid increase in woody plant at rates un-anticipated by the models. Contrary to early projections for the Succulent Karoo biome, biomass and cover have increased, largely in response to changes in land-use practices. Cover in the fire-adapted Fynbos biome has remained stable or increased over time with unanticipated expansion of forest species, particularly in localities protected from fire for long periods. The shrub-dominated Nama-karoo biome has increased in grass cover. Rather than contracting, as suggested in the early models, the Grassland biome has apparently expanded westwards into former Nama-karoo biome sites. The Savanna biome has experienced a rapid increase in woody plants at rates not anticipated by the models. The broad trends in historical trajectories illustrate how land-use management has influenced vegetation change in the past. They also provide a useful context for evaluating future changes and developing mitigation strategies for some of the worst impacts of climate change in the future.

Long-term changes in land use, land cover and vegetation in the Karoo drylands of South Africa: implications for degradation monitoring

We used several large data sets at a range of temporal and spatial scales to document the land-use/land-cover change (LULCC) dynamics of the semi-arid Succulent Karoo and Nama-Karoo biomes of South Africa. More than 95% of the Karoo is comprised of land classified as Natural, which has been relatively stable since 1990. Over the last 100 years cultivation, as well as the number of domestic livestock, has declined significantly in both biomes. Protected areas have increased since 1980 to comprise nearly 8% of the Succulent Karoo biome, although they only cover 1.6% of the Nama-Karoo biome. There has been a significant recent increase in renewable energy installation applications, which cover 4% of the Karoo drylands. The trend in vegetation productivity (NDVI; 1982–2015) is unchanged over 90% of both biomes, while nearly 10% of the Karoo has shown a significant increase in NDVI trend. An analysis of repeat photographs shows that vegetation cover has either remained unchanged or has increased at most locations. Although the Karoo drylands appear less degraded than they were in the mid-twentieth century, on-going monitoring at different temporal and spatial scales is essential to evaluate the future impact of LULCC on these semi-arid environments.

Vegetation responses to seasonal weather conditions and decreasing grazing pressure in the arid Succulent Karoo of South Africa

The Succulent Karoo biome is a renowned centre of biodiversity and endemism in the arid winter rainfall region of South Africa that is threatened by climate change. On 20 permanently marked plots within a biodiversity observatory, species richness and cover were assessed annually from 2002 to 2017 during the growing season. We were interested, firstly, in whether the vegetation showed any trends in response to the strong decrease in grazing pressure, which occurred at the beginning of the monitoring period, and secondly, in the effect of seasonal climate on the vegetation. We analysed the responses of species richness and cover in four life forms to seasonal rainfall and the standardised precipitation–evapotranspiration index (SPEI) using linear mixed-effect models. Time had a positive effect on richness of annual species and a negative effect on cover of shrubs and annuals, which increased in response to SPEI and less strongly to rainfall during autumn and winter. Habitat did not have any effect and geophytes and perennial herbs did not show any significant response. The importance of SPEI during autumn and winter is discussed in relation to potential germination cues and the projected decrease in rainfall and increase in temperature during these seasons.

Crassula, insights into an old, arid-adapted group of southern African leaf-succulents

The Crassulaceae is an important family in the Greater Cape Floristic Region of southern Africa and is the seventh largest family in the arid Succulent Karoo Biome. After the Aizoaceae it is the largest group of leaf-succulents in southern Africa.This is the first investigation of a broad selection (68%) of the ±170 species of Crassula. We used data from three chloroplast and two nuclear gene-regions, which yielded many informative characters and provided good resolution among the species.We show that only five of the 20 sections in Crassula are monophyletic. However, the clades recovered show close correlation with the two subgenera that were once recognized. Crassula contains more than 25 succulent annual species which are not closely related to each other but form early-diverging branches in each of the three major clades. One of these major clades contains far more perennial species than the others and is the greatest diversification within Crassula. This diversification mostly arose within the last 10 million years (my) and spread across much of southern Africa. Members of the smaller two major clades are often soft- and flat-leaved perennials (many with basic chromosome number x = 8, with high levels of polyploidy). Those in the largest diversification (where a basic chromosome number of x = 7 predominates) show other arid-adaptations (more highly succulent leaves with a dense covering of hairs or papillae or a smooth xeromorphic epidermis). Their flowers are also more variable in shape and bee-, moth- and butterfly-pollinated species are known among them.We establish that Crassula arose in the Greater Cape Floristic Region of southern Africa. While much of its diversity has evolved in the last 10 my, Crassula nevertheless contains species that are much older and itself arose ±46 my ago. Since all its species are succulent it is possible that they are part of an early arid-adapted flora that contributed to the Succulent Karoo Biome in the western part of southern Africa. Consequently this Biome may not be assembled only from ‘young lineages’ as is usually thought to be the case.

Climatic buffering and anthropogenic degradation of a Mediterranean-type shrubland refugium at its semi-arid boundary, South Africa

The mega-diverse, Mediterranean-type fynbos biome may be vulnerable to future changes in climate and associated fire regimes, in particular to increasing summer-drought intensity and associated potential expansion of adjacent semi-arid vegetation types. Studying Holocene vegetation dynamics at the fynbos–succulent karoo boundary may provide insights into the resilience or sensitivity of fynbos to climate change. In this study, fossil pollen, non-pollen palynomorphs and charcoal data spanning ~5500 to −50 cal. yr BP were generated from an accelerator mass spectrometer (AMS) radiocarbon-dated sediment core extracted directly at the present-day fynbos–succulent karoo biome boundary at Groenkloof, a site in the Kamiesberg Mountains of Namaqualand, South Africa. Contrary to expectations, during the Mid-Holocene Altithermal from 5480 to 4025 cal. yr BP, fynbos and fire thrived through summer moisture subsidies associated with enhanced sub-tropical easterly flow. Subsequent cooling from 4025 to 2005 cal. yr BP resulted in enhanced summer drought and overall fynbos biome contraction, though woody fynbos shrubs persisted through physiological adaptations to drought. Desert succulents typical of the succulent karoo, such as those of Aizoaceae and Crassulaceae, failed to colonise the emergent niche space, resulting in dominance of an ambiguous grassy, asteraceous fynbos. More recent wetting associated with the ‘Little Ice Age’ Holocene temperature minima from 695 to 100 cal. yr BP prompted a resurgence in fynbos abundance, but frequent fire driven by pastoralists appears to have reduced the fynbos community’s functional diversity. Palaeoecological data from the Kamiesberg suggest that both climatic buffering of mountain refugia and high physiological resistance among certain fynbos taxa have contributed to the biome’s long-term resilience. Summer rainfall associated with the sub-tropical easterlies has been key in maintaining eastern fynbos refugia in past interglacial temperature maxima. The data also suggest that pre-historic land use and resulting fire-regime manipulations have resulted in the development of a taxonomically and functionally simplified alternative fynbos ecosystem state.

Water beetles from the Bokkeveld Plateau: a semi-arid hotspot of freshwater biodiversity in the Northern Cape of South Africa.

The Bokkeveld Plateau in the Northern Cape of South Africa supports a complex transition zone between the fynbos and succulent karoo biomes on the margins of Namaqualand. A combination of regular winter rainfall, geology and strong rainfall gradients mean that the region supports a diverse and highly endemic flora. Recent sampling of aquatic beetles in the Bokkeveld demonstrates that this region also has a diverse freshwater fauna, including a number of apparent endemics. Five new species of Hydraenidae (Pterosthetops chrysomallus sp. nov., Parastetops porcellus sp. nov., Mesoceration castaneum sp. nov., M. chasmum sp. nov., and M. sabulosum sp. nov.) are described from the Bokkeveld, and new records provided for 68 other water beetle taxa recorded during recent fieldwork in the region, 28 of which are new to Northern Cape Province. Most of the newly described species are relatively common in the region, suggesting that additional taxa may remain undetected in this apparent hotspot of freshwater diversity.

Impact of the Future Changing Climate on the Southern Africa Biomes, and the Importance of Geology

The Southern African biomes are complex biotic communities, with its distinctive plant and animal species, and are maintained under the suitable climatic conditions of the region. It includes the Fynbos Biome and the Succulent Karoo Biome, which forms the smallest of the world’s six Floristic Kingdoms, and they are of conservation concern. The other six biomes are Albany Thicket, Desert, Grassland, Indian Ocean Coastal belt, Nama-Karoo, Savanna. The biomes are not only threatened by agricultural expansion, overgrazing, and mining; but also by future climate changes and droughts. This study investigates the how to best model the possible vulnerable biome areas, under future climate changes, and how Southern African geology plays a huge role in the restriction of the biome shifts. It provides evidence regarding the importance of the study to understanding the climate change impacts and the geological variables on the Southern African biomes, in terms of possible future biome habitat loss.

Evolutionary history of a keystone pollinator parallels the biome occupancy of angiosperms in the Greater Cape Floristic Region

The Greater Cape Floristic Region (GCFR) in South Africa has been extensively investigated for its phenomenal angiosperm diversity. A key emergent pattern is the occurrence of older plant lineages in the southern Fynbos biome and younger lineages in the northern Succulent Karoo biome. We know practically nothing, however, about the evolutionary history of the animals that pollinate this often highly-specialized flora. In this study, we explore the evolutionary history of an important GCFR fly pollinator, Megapalpus capensis, and ask whether it exhibits broadly congruent genetic structuring and timing of diversification to flowering plants within these biomes. We find that the oldest M. capensis lineages originated in Fynbos during the Miocene, while younger Succulent Karoo lineages diverged in the Pliocene and correspond to the proposed age of this recent biome. A strong signature of population expansion is also recovered for flies in this arid biome, consistent with recent colonization. Our first investigation into the evolutionary history of GCFR pollinators thus supports a recent origin of the SK biome, as inferred from angiosperm phylogenies, and suggests that plants and pollinators may have co-diverged within this remarkable area.

A new monotypic genus, a species synonymy and nomenclatural corrections in the arid-adapted Canthonini (Scarabaeidae, Scarabaeinae) from the Succulent Karoo Biome of south-western Africa.

Although it has been demonstrated that the tribe Canthonini (Scarabaeidae: Scarabaeinae) is polyphyletic, those canthonine genera occurring in arid south-western Africa apparently form a monophyletic group. In this paper we add one new monotypic genus, Drogo stalsi gen. et. sp. n. to this group, and synonymize another member, Byrrhidium namaquense Scholtz and Howden, 1987 syn. n. with Byrrhidium ovale Harold, 1869. We correct the spelling of two species names that were not in agreement with the gender rule. A phylogenetic analysis based on morphology supports the erection of Drogo gen. n. An updated key to the genera and species of the Byrrhidium group is presented.

A new species of Anacaena Thomson, 1859 from South Africa (Coleoptera: Hydrophilidae).

Anacaena namaqua sp. nov. is described from the Northern Cape and Western Cape provinces of South Africa, in an area transitional between the fynbos and succulent karoo biomes. The habitus, aedeagus, femoral pubescence and habitats of the new species are illustrated, together with details of its ecology. A key to all Anacaena confirmed from South Africa to date is also provided.

The distribution of the dwarf succulent genus <i>Conophytum</i> N.E.Br. (Aizoaceae) in southern Africa

Background: The dwarf succulent genus Conophytum N.E.Br. is one of the most species rich in the Aizoceae. The genus is most closely associated with a region of high floral endemism and biodiversity, the Succulent Karoo biome in south-western Africa.Objectives: To examine the distribution of Conophytum in south-western Namibia and in the Northern and Western Cape Provinces of South Africa.Method: A database comprising 2798 locality records representing all known species and subspecies of the genus Conophytum has been constructed.Results: The genus is primarily restricted to the arid winter-rainfall region of the Northern and Western Cape Provinces of South Africa and south-western Namibia, within the Greater Cape Floristic Region. Whilst taxa are found across all the main biomes in the region (the Succulent Karoo, Nama Karoo, Desert and Fynbos biomes), 94% of Conophytum taxa are found only in the Succulent Karoo biome and predominantly (88% of taxa) within South Africa. Endemism within specific bioregions is a feature of the genus and ~60% of taxa are endemic to the Succulent Karoo. Approximately 28% of all taxa could be considered point endemics. Whilst the genus has a relatively wide geographical range, we identify a pronounced centre of endemism in the southern Richtersveld.Conclusion: The genus Conophytum can be used as a good botanical model for studying patterns of diversity and speciation in the Succulent Karoo biome, the effects of climate change on dwarf succulents, and for informing conservation planning efforts.