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Scientific Name | Gibbaeum esterhuyseniae L.Bolus |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A2ac; B1ab(iii,v)+2ab(iii,v); C2a(ii); D |
Assessment Date | 2021/03/23 |
Assessor(s) | C. Klak, J.H. Vlok, D. Raimondo & D. Kirkwood |
Justification | This range-restricted species has an extent of occurrence (EOO) and area of occupancy (AOO) of <10 km². This species has lost habitat in the past to forestry plantations and crop cultivation. The population remains at one location and is under heavy predation pressure by porcupines with over 90% of the population lost to predation in 2020. It therefore qualifies for listing as Critically Endangered under criteria A,B,C, and D. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This Western Cape endemic has a very limited distribution between McGregor and Bonnievale. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Breede Shale Renosterveld, Central Ruens Shale Renosterveld |
Description | It is confined to shale overlaying quartz. |
Threats |
| Historical records of this species show that it once had a larger range (EOO 164 km²) between Bonnievale, McGregor and Stormsvlei. Forty six % (46%) of its former habitat has been irreversibly modified for crop cultivation and bluegum plantation. The remaining subpopulation is under severe predation by porcupines. Area where this species is found is suitable for ostrich farming - this poses a future potential threat (J.Vlok 2006). |
Population |
This species remains growing on one farm in its range and is under severe predation pressure, with only 6 plants found surviving in good condition in 2020 (Keir and Alouise Lynch pers. obs.). Seeds and capsules were collected for ex-situ conservation at the Stellenbosch Botanic Gardens, with a possibility of reintroducing plants in the near future. The population continues to decline and requires ongoing monitoring.
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Population trend | Decreasing |
Conservation |
| This species is protected in Karoo National Botanic Garden, Worcester. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Gibbaeum esterhuyseniae L.Bolus | CR B1ab(iii,v)+2ab(iii,v) | Raimondo et al. (2009) | | Gibbaeum esterhuyseniae L.Bolus | Endangered | Hilton-Taylor (1996) | | Gibbaeum esterhuyseniae L.Bolus | Extinct | Hall et al. (1980) | |
Bibliography |
Goldblatt, P. and Manning, J.C. 2000. Cape Plants: A conspectus of the Cape Flora of South Africa. Strelitzia 9. National Botanical Institute, Cape Town.
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.
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Citation |
| Klak, C., Vlok, J.H., Raimondo, D. & Kirkwood, D. 2021. Gibbaeum esterhuyseniae L.Bolus. National Assessment: Red List of South African Plants version . Accessed on 2024/10/08 |
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