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Scientific Name | Diastella thymelaeoides (P.J.Bergius) Rourke subsp. thymelaeoides |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Synonyms | Diastella bryiflora Salisb. ex Knight, Paranomus concavus (Lam.) Kuntze |
Common Names | Kogelberg Silkypuff (e) |
National Status |
Status and Criteria | Near Threatened B1ab(iii,v)+2ab(iii,v) |
Assessment Date | 2020/04/20 |
Assessor(s) | A.G. Rebelo, H. Mtshali & L. von Staden |
Justification | Diastella thymelaeoides subsp. thymelaeoidess has a very restricted range, with an extent of occurrence (EOO) of 359 km², and an area of occupancy (AOO) of 156 km², occurring at between 12 and 15 locations. Alien invasive plants, particularly escaped pine seedlings, continue to spread into its habitat, and along with harvesting for the cut flower industry is causing ongoing decline in habitat quality and the number of mature individuals. It therefore nearly meets the criteria thresholds for Vulnerable under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is endemic to the Western Cape mountains in South Africa, where it is known from Hottentots-Holland Mountains and northern Kogelberg. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Kogelberg Sandstone Fynbos |
Description | It occurs on sandstone slopes in montane fynbos, at 100-1000 m.a.s.l. Mature individuals are killed by fires, and only seeds survive. Seeds are released after ripening, and dispersed by ants to their underground nests, where they are protected from predation and fire. It is pollinated by insects. |
Threats |
| A very small proportion (14%) of this subspecies' habitat was lost to timber plantations in the past. There is no significant ongoing habitat loss, and most of this species' habitat is now formally protected. Timber plantations are however a major source of alien invasive plants, particularly escaped pine seedlings that are invading surrounding native vegetation (mainly in Steenbras Dam), and outcompeting native species when they become dense. A further threat is harvesting for the cut flower trade this only effects the portion of the population occuring in the Steenbras Dam area. |
Population |
This subspecies occurs as isolated patches of a few dozen plants. The isolated subpopulations to the northeast and east of Steenbras Dam could not be found during the Protea Atlas project, and the habitat is totally converted. If the Steenbras Catchment area is kept clear of aliens and picking of wild flowers terminated, this species could be adequately protected. Population reduction is inferred due to harvesting and ongoing degradation of habitat by alien invasive plants.
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Population trend | Decreasing |
Conservation |
| Some 20 % of subpopulations are conserved in the Kogelberg Nature Reserve. The Steenbras Catchment area where most plants occur is being managed for conservation, but flower harvesting is ongoing and needs to be curtailed. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Diastella thymelaeoides (P.J.Bergius) Rourke subsp. thymelaeoides | NT B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v) | Raimondo et al. (2009) | | Diastella thymelaeoides (P.J.Bergius) Rourke subsp. thymelaeoides | Rare | Hilton-Taylor (1996) | |
Bibliography |
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.
Rebelo, T. 2001. Sasol Proteas: A field guide to the proteas of southern Africa. (2nd ed.). Fernwood Press, Vlaeberg, Cape Town.
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Citation |
| Rebelo, A.G., Mtshali, H. & von Staden, L. 2020. Diastella thymelaeoides (P.J.Bergius) Rourke subsp. thymelaeoides. National Assessment: Red List of South African Plants version . Accessed on 2025/05/12 |
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