|
Scientific Name | Leucospermum formosum (Andrews) Sweet |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Common Names | Silver-leaf Wheel Pincushion (e) |
National Status |
Status and Criteria | Endangered B2ab(iii,v); C1 |
Assessment Date | 2020/05/21 |
Assessor(s) | A.G. Rebelo, D. Raimondo, L. von Staden & A.L. Schutte-Vlok |
Justification | Leucospermum formosum is a species that occurs as disjunct subpopulations limited to wet south-facing slopes of the mountains of the southern Cape. Formerly occurring on the Riviersonderend, Langeberg and Outeniqua mountains, the subpopulations on the Riviersonderend mountains were small in the late 1990s and have likely been lost here due to severe habitat degradation as a result of alien plant species invasions and too frequent fires. There is thus uncertainty in the extent of occurrence (EOO) which could range between 2236 km² and 5775 km² depending on whether the Riviersonderend subpopulations are still extant. The area of occupancy (AOO) ranges from 80-96 km². The subpopulations on the Langeberg Mountains have not been recorded for 20 years and are suspected to have declined significantly. This species is known from between three and five locations. At least 20% of the population is suspected to have declined in the past 30 years (two generations) due to competition from invasive alien plant species, and inappropriate fire return intervals. This species therefore qualifies as Endangered under criteria B and C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is known from Riviersonderend to Outeniqua Mountains, in the Western Cape Province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | South Outeniqua Sandstone Fynbos, South Langeberg Sandstone Fynbos, South Sonderend Sandstone Fynbos |
Description | It occurs in sandstone fynbos, usually on wet south-facing slopes. 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 birds. |
Threats |
| This species has lost habitat in the past to afforestation (pine plantations) as well as urban development for the town of George. This species ecology is tightly linked to natural fire cycles in the fynbos, it requires fire to recruit and fire return intervals of between 15 and 20 years is required to ensure sufficient seeds are available to maintain viable populations. It is currently threatened by inappropriate fire regimes. Short fire return intervals (two fires in the space of 10 years) has occurred at the Attakwaskloof subpopulations and impacted more than 50% of the Riviersonderend Mountain subpopulation. Lack of burning due to proximity of subpopulations to pine plantations is also a threat causing declines to the Ruitersbos and Moordkuyl subpopulations. Invasive alien plants in particular Hakea, Pinus and Acacia mearnsii species are causing ongoing habitat degradation at all remaining subpopulations. Another potential threat is invasive ant species that displace native ant species. Invasive ants do not perform the function of indigenous ants, which is to bury this species' seeds in their nests where they are protected from predation by rodents. Large scale ant invasions could lead to population collapse if there is no soil-stored seed bank to regenerate from post fire. |
Population |
This species is known from a number of disjunct subpopulations. The largest subpopulations occur in the Outeniqua Mountains. There are three subpopulations known from the Outeniquas, the largest occurs at the Ruiterbos Forest Station extending up Robinson's Pass where between 300 and 500 individuals have been monitored in 1996 and again in 2005, while a full survey of the site has not been completed recently one stand of 50 plants was observed in 2019, the subpopulation is likely to still consist of between 250 and 300 plants. A second subpopulation of around 300 plants occurs at Moordkuyl and a smaller subpopulation of between 50 and 100 plants occurs at Attakwaskloof. The two later subpopulations were last monitored in 2005 and it is possible that numbers have declined especially at Attakwaskloof due to too frequent fires. In the Langeberg Mountains there are two subpopulations at Dassiehoek these were both smaller than 50 plants in 1996 and their current status is unknown. In the Riviersonderend Mountains, three small isolated stands were recorded between 1993 and 1996, these have been impacted by too frequent fire and severe infestations of invasive alien plants and are suspected to be extinct. From herbarium records a further three subpopulations at Garcias Pass, Duiwelskop, and Pacaltsdorp can be confirmed to have been lost, these were all last recorded prior to 1900.
|
Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Leucospermum formosum (Andrews) Sweet | EN A3c+4c; B1ab(ii,iii,v)c(iv)+2ab(ii,iii,v)c(iv) | Raimondo et al. (2009) | | Leucospermum formosum (Andrews) Sweet | Vulnerable | Hilton-Taylor (1996) | | Leucospermum formosum (Andrews) Sweet | Rare | 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.
Manning, J.C. and Goldblatt, P. 2012. Plants of the Greater Cape Floristic Region 1: The Core Cape Flora. Strelitzia 29. South African National Biodiversity 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.
|
Citation |
| Rebelo, A.G., Raimondo, D., von Staden, L. & Schutte-Vlok, A.L. 2020. Leucospermum formosum (Andrews) Sweet. National Assessment: Red List of South African Plants version . Accessed on 2025/05/15 |
Comment on this assessment
