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Scientific Name | Stapelia hirsuta L. var. gariepensis (Pillans) Bruyns |
Higher Classification | Dicotyledons |
Family | APOCYNACEAE |
Synonyms | Gonostemon gariepensis (Pillans) P.V.Heath, Stapelia gariepensis Pillans, Stapelia johni-lavrani Halda |
National Status |
Status and Criteria | Critically Endangered A2ac+4ac |
Assessment Date | 2022/12/08 |
Assessor(s) | P.C.V. Van Wyk & D. Raimondo |
Justification | This taxon is endemic to the Richtersveld and Sperrgebiet regions of South Africa and Namibia. The South African portion of the population is limited to a small area along the Orange River and northern mountains of the Richtersveld National Park where it has an extent of occurrence (EOO) of 779 km² and an area of occupancy (AOO) of 60 km². Six to ten locations are currently declining due to the impacts of open-cast mining and habitat degradation as a result of overgrazing by livestock that took place between 2002 and 2016. Between 80 and 90% of the population has declined due to these pressures since 2002. In addition 50% of the remaining South African population falls within the proposed footprint for the development of the infrastructure associated with Boegoebaai Port and the green hydrogen plant, should this go ahead a further 50% of the population will be lost by 2032. Since this species has a generation length of at least 20 years, at the national scale this taxon qualifies for listing as Critically Endangered under criterion A. While it also occurs in Namibia, subpopulations there are isolated to remote mountains and are also suspected to be declining due to climate change, the regional status of Critically Endangered is therefore not downgraded. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | Northern Cape |
Range | It is restricted to the Sperrgebiet region of Namibia and the northern parts of the Richtersveld region in South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Desert |
Description | Grows amongst rocks or in flat loamy areas, often occurring under the shelter of bushes. Seeds do not have long dormancy and thus seed backs are limited. |
Threats |
| This taxon is threatened by current and future habitat loss and degradation. The portion of the population within South Africa occurs only along the Orange River and within the Richtersveld National Park. Along the Orange River it occurs in the area where open-cast mining is taking place. Degradation extends far beyond the mining sites due to windblown dust from mining disturbance and exposed mine dumps covering large areas, burying this taxon's habitat in sand. Half of the South African portion of the population also falls within the footprint of the Boegoebaai Port development project being planned for implementation over the next 10 years. This development includes the construction of a Port for deep sea vessels, railway line and several refineries for oil and other minerals as well as extensive renewable energy facilities to power a green hydrogen generating facility. The population is furthermore declining due to climate change. Its entire range has experienced below average rainfall since 2012. Predictions of future climate change include further increases in annual average temperature of between 1.4°C and 2.4°C by 2050, which will result in unbearably hot temperatures and ongoing aridification throughout significant portions of the year (Van Wilgen et al. 2017). Within South Africa it has also lost habitat to severe overgrazing by livestock between the years 2002 and 2016. |
Population |
The South African portion of the population is declining rapidly due to the combined impacts of mining, livestock overgrazing and drought. For example, the subpopulation on Hellskloof in the Richtersveld National Park declined by 95% between 2016 and 2021 due to the combined impact of loss of shrub cover and top soil from severe overgrazing and the subsequent impacts of drought. Since this was the largest known subpopulation and declines have also been observed elsewhere within its South African range we infer that a decline of between 80 and 90% of the population has taken place since 2002. Furthermore over 50% of the South African portion of the population falls within the proposed Boegoebaai, Green Hydrogen development zone. This means that ongoing population decline is expected to take place due to this development in the next 10 years. The Namibian portion of the population is known from more remote mountains, and it is not known if this portion of the population is declining but it is suspected to have experienced loss due to the impacts of the extended drought.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Stapelia hirsuta L. var. gariepensis (Pillans) Bruyns | Least Concern | Raimondo et al. (2009) | | Stapelia gariepensis Pillans | Not Threatened | Hilton-Taylor (1996) | | Stapelia gariepensis Pillans | Uncertain | Hall et al. (1980) | |
Bibliography |
Bruyns, P.V. 2005. Stapeliads of southern Africa and Madagascar. (Vol. 1, pp. 1-330). Umdaus Press, Pretoria.
Hall, A.V., De Winter, M., De Winter, B. and Van Oosterhout, S.A.M. 1980. Threatened plants of southern Africa. South African National Scienctific Programmes Report 45. CSIR, Pretoria.
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
Van Wilgen, N.J. and Herbst, M. 2017. Taking stock of parks in a changing world: The SANParks Global Environmental Change Assessment. SANParks, Cape Town.
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Citation |
| Van Wyk, P.C.V. & Raimondo, D. 2022. Stapelia hirsuta L. var. gariepensis (Pillans) Bruyns. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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