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Scientific Name | Trichodiadema pygmaeum L.Bolus |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Endangered B1ab(iii,v) |
Assessment Date | 2016/01/18 |
Assessor(s) | L. von Staden |
Justification | EOO 2992 km², 13 severely fragmented remaining subpopulations continue to decline due to ongoing habitat loss and degradation. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | Swellendam to Cape Infanta. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Eastern Ruens Shale Renosterveld, Central Ruens Shale Renosterveld, Western Ruens Shale Renosterveld, Ruens Silcrete Renosterveld, Swellendam Silcrete Fynbos |
Description | Quartz outcrops in shale and silcrete renosterveld. |
Threats |
| Less than 10% of shale and silcrete renosterveld in the Overberg remains intact after extensive loss to crop cultivation. This species occurs on somewhat shallower soils that are not suitable for cultivation, but there has been some opportunistic ploughing of some areas in the past. Small remaining fragments are often overstocked with livestock, and grazing and trampling due to overgrazing and overstocking is the most severe ongoing threat to this species, affecting at least 50% of remaining subpopulations. Some sites are also invaded with alien invasive plants, which could potentially outcompete native species if left unmanaged. |
Population |
About 13 subpopulations are known to remain, and 12 of these occur on small, isolated renosterveld fragments. Field observations indicate that subpopulations are small, and the population is therefore considered severely fragmented. It continues to decline due to ongoing habitat loss and degradation.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Trichodiadema pygmaeum L.Bolus | EN B1ab(iii,v) | 2017.1 | | Trichodiadema pygmaeum L.Bolus | VU D2 | Raimondo et al. (2009) | | Trichodiadema pygmaeum L.Bolus | Rare | Hilton-Taylor (1996) | | Trichodiadema pygmaeum L.Bolus | 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 |
| von Staden, L. 2016. Trichodiadema pygmaeum L.Bolus. National Assessment: Red List of South African Plants version . Accessed on 2025/05/19 |
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