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Scientific Name | Mimetes argenteus Salisb. ex Knight |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Synonyms | Mimetes nitens (Thunb.) Roem. & Schult. |
Common Names | Silver Pagoda (e), Silver-leaved Bottlebrush (e), Vaalstompie (a) |
National Status |
Status and Criteria | Endangered A2ace; C2a(ii) |
Assessment Date | 2020/04/20 |
Assessor(s) | A.G. Rebelo, D. Raimondo, N.A. Helme & L. von Staden |
Justification | Mimetes argenteus is a restricted endemic to the Fynbos Biome, South Africa. This species has an extent of occurrence (EOO) of 1201 km² and an area of occupancy (AOO) of 124 km². It is a habitat specialist and is confined to seep habitats on mountain slopes. Monitoring of stands of plants since 1995 indicates that there has been a decline of between 68 and 77% due to the combined impacts of this species susceptibility to Phytophthora infection and too frequent fire return intervals. Decline in the number of mature individuals is ongoing. The total population size is estimated to be between 350 and 640 plants, no subpopulation has more than 250 mature individuals. With a generation length of 15 - 20 years this species qualifies for listing as Endangered under criteria A and C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This is an endemic species to the mountains of the Western Cape South Africa, occurring along the Hottentots Holland, Franschhoek and Riviersonderend Mountains. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | South Sonderend Sandstone Fynbos, Kogelberg Sandstone Fynbos, Hawequas Sandstone Fynbos |
Description | It occurs in sandstone fynbos on peat seeps. 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 typically occurs as small localized stands of individuals which are vulnerable to the impacts of too-frequent fire. There has been documented decline in four subpopulations over the past 25 years. Furthermore this species is highly susceptible to Phytophthora attack with typically 30% of individuals in recorded subpopulation noted as having died due to Phytophthora. A further threat is groundwater abstraction. This species only occurs in peat seeps which are fed by ground water. There are currently proposals to extract ground water from a number of sites in the Hottentot Holland Mountains in order to supply the City of Cape Town with water. Lastly invasive alien pines and hakeas have been recorded throughout this species range and are becoming a severe threat on the Riviersonderend Mountains. |
Population |
This species occurs as localized clumps of plants associated with seeps, scattered along three mountain chains. During the Protea Atlas project five large subpopulations of between 100 and 200 plants were recorded at the following sites Moodenaarskop; Dwarsberg on the Hottentot-Holland Mountains; Bloukop on the Franshoek Mountains, and Nooitgedaagt and Pilaarkop on the Riviersonderend Mountains. The subpopulations at Moodenaarskop, Dwarsberg and Bloukop have all been recently monitored showing a dramatic decline of individuals at all three sites with between 20 and 40 plants extant at each location. Decline at Bloukop has been documented to be as a result of too frequent fire return intervals. While the Pilaarkop and Nooitgedaagt subpopulations have not been remonitored, the slopes of the Riviersonderend mountain have experienced dramatic spread of invasive alien pines and hakeas, furthermore too frequent fire is also a concern. These subpopulations thus also highly likely to have declined. In addition, a further twenty small stands of between 5 and 20 plants occur scattered along these three mountain chains. There is an ongoing decline in the number of mature individuals taking place as a result of this species susceptibility to Phytophthora. Overall the population is estimated to have consisted of between 1500 and 2000 plants in 1996, over a three generation time period it has declined to between 350 and 640 plants, representing a plausible range of decline in the past three generation of between 68% and 77%.
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Population trend | Decreasing |
Conservation |
| It is conserved in Hottentot Holland, Theewaters, Riviersonderend and Greyton Nature Reserves. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Mimetes argenteus Salisb. ex Knight | EN B1ab(iii,v)c(iv)+2ab(iii,v)c(iv) | Raimondo et al. (2009) | | Mimetes argenteus Salisb. ex Knight | Rare | Hilton-Taylor (1996) | |
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.
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., Raimondo, D., Helme, N.A. & von Staden, L. 2020. Mimetes argenteus Salisb. ex Knight. National Assessment: Red List of South African Plants version . Accessed on 2025/05/12 |
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