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Scientific Name | Cheiridopsis verrucosa L.Bolus |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Cheiridopsis mirabilis Schwantes, Cheiridopsis verrucosa L.Bolus var. minor L.Bolus |
National Status |
Status and Criteria | Critically Endangered A2ace+3ce+4ace; B1ab(i,ii,iii,iv,v) |
Assessment Date | 2022/09/20 |
Assessor(s) | P.C.V. Van Wyk & D. Raimondo |
Justification | This dwarf deciduous species is rare, and has a restricted range occurring only in the Gariep Valley in north west South Africa and southern Namibia. Its extent of occurrence (EOO) and area of occupancy (AOO) in South Africa is 40 km². There is one location and the population is currently declining rapidly due to habitat degradation from mining and drought-related mortality linked to climate change. The entire population is projected to be lost by the year 2060 as a result of the planned Boegoebaai Port development project. This species' generation length is suspected to be 30-50 years. It therefore qualifies for listing as Critically Endangered under criteria A and B. Given that subpopulations from Namibia are also declining the regional status is not downgraded. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | Northern Cape |
Range | Endemic to the Sperrgebiet region of Namibia and the Richtersveld region of South Africa, this species occurs near Oranjemund in Namibia and east of Alexander Bay near Grootderm and Beauvallon. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Desert |
Description | It grows in sand-filled crevices on shale or dolomite substrates. It is slow growing, with a generation length that is suspected to be between 30 and 50 years. Furthermore, monitoring of subpopulations over the past 23 years indicates that recruitment rarely occurs. |
Threats |
| The entire range of this species within South Africa falls within the Boegoebaai Port Development Project 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 green hydrogen production. Should this development go ahead all remaining habitat within South Africa will be lost. Similar green hydrogen mining projects are being planned for the Namibian portion of its range. The population is also currently declining in South Africa due to off road driving of mining vehicles as well as by four by four enthusiasts. There are only two subpopulations known from Namibia, one falls within a reserve that is popular with tourists, and monitoring data indicates that plants have been removed from their habitat most likely for ornamental horticultural purposes. The second subpopulation is threatened by mining. Abiotic changes linked to global change are already being experienced in the Richtersveld and Sperrgebiet regions and are expected to intensify into the future, with observed temperature change over the past 10 years already reaching those predicted for near future scenarios (2035) (Van Wilgen et al. 2016). Significant drought related mortality has been observed during monitoring that took place in the year 2021. |
Population |
This species is known from only two subpopulations in Namibia and between 8 and 10 subpopulations in South Africa. The population is declining rapidly. Monitoring of five of the remaining subpopulations within the South African portion of its range in 2021 indicated that greater than 80% of plants died due to drought-related mortality since 2016. Similar mortality levels are suspected to have occurred in Namibia. The subpopulation within a reserve in Namibia has also declined due to illegal collection with 30% of monitored individuals being lost between 2018 and 2021. With all of the remaining subpopulations in South Africa occurring within the area earmarked for the Bogoebaai Port Development Project, similar green hydrogen projects being planned for its range in Namibia, and climate models predicting ongoing aridification, a further decline of between 80 and 100% is expected to occur within the next 60 years.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Cheiridopsis verrucosa L.Bolus | Least Concern | Raimondo et al. (2009) | |
Bibliography |
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.
Snijman, D.A. 2013. Plants of the Greater Cape Floristic Region 2: The extra Cape flora. Strelitzia 30. South African National Biodiversity Institute, Pretoria.
Van Wilgen, N.J., Goodall, V., Holness, S., Chown, S.L. and M.A., M. 2016. Rising temperatures and changing rainfall patterns in South Africa's national parks. International Journal of Climatology 36(2):706-721.
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Citation |
| Van Wyk, P.C.V. & Raimondo, D. 2022. Cheiridopsis verrucosa L.Bolus. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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