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Scientific Name | Arctotheca forbesiana (DC.) K.Lewin |
Higher Classification | Dicotyledons |
Family | ASTERACEAE |
Synonyms | Cryptostemma forbesianum (DC.) Harv., Gazania forbesiana DC. |
National Status |
Status and Criteria | Vulnerable A3c; B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v); C1 |
Assessment Date | 2011/06/14 |
Assessor(s) | N.A. Helme & D. Raimondo |
Justification | EOO 4 266 km², AOO <10 km², and nine remaining locations. This species' habitat has mostly been lost to wheat cultivation and the urban expansion of the Cape Flats and the Strand area over the past 80 years, and all possible remaining habitat totals <10 km². It continues to be severely threatened by ongoing habitat loss to urban expansion, severe overgrazing, and degradation of wetland habitats due to eutrophication and alien grass invasion. Of nine remaining subpopulations, totalling less than 4 000 mature individuals, six are in imminent danger of extirpation (most were found as part of Environmental Impact Assessment surveys), which is likely to result in a 30-40% population reduction within the next 10 years. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | Malmesbury to Somerset West, Caledon and Elim. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Cape Flats Dune Strandveld, Swartland Shale Renosterveld, Western Ruens Shale Renosterveld, Peninsula Shale Renosterveld, Swartland Silcrete Renosterveld, Elim Ferricrete Fynbos, Cape Flats Sand Fynbos, Atlantis Sand Fynbos, Lourensford Alluvium Fynbos |
Description | Seasonally wet to flooded shale, silty clay lowlands associated with silcrete and ferricrete. |
Threats |
| Urban expansion is a severe past, present and future threat. The Faure, Kraaifontein and Raapenberg subpopulations have been lost in the past, the subpopulation at Strand is currently under severe threat of development. Expansion of low cost housing at the Caledon site is also highly likely.
Agriculture was a severe past threat especially in the areas south of Malmesbury and in the western portion of the Overberg.
Alien grass invasion is an ongoing threat to many of the remaining subpopulations. |
Population |
This species' habitat is extensively transformed, and all nine known remaining subpopulations are confined to small fragments. Subpopulations on small, degraded lowland sites are all very small, consisting of between 50 and 250 mature individuals, however, two subpopulations on sites managed for conservation each consist of at least 1 000 plants. Six subpopulations occur in highly transformed urban and agricultural areas, and are in imminent danger of extirpation due to urban development and severe overgrazing. Many recently discovered subpopulations were found in Environmental Impact Assessment surveys for proposed developments. As a result of continuing loss and degradation of lowland wetland habitats it is projected that the population will decline by 30-40% within the next 10 years, but will probably not exceed 40% as long as the two largest subpopulations remain well conserved.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Arctotheca forbesiana (DC.) K.Lewin | CR B2ab(ii,iii,iv,v) | Raimondo et al. (2009) | | Arctotheca forbesiana (DC.) K.Lewin | Indeterminate | Hilton-Taylor (1996) | | Arctotheca forbesiana (DC.) K.Lewin | Indeterminate | 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 |
| Helme, N.A. & Raimondo, D. 2011. Arctotheca forbesiana (DC.) K.Lewin. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14 |
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