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Scientific Name | Serruria altiscapa Rourke |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Common Names | Stately Spiderhead (e) |
National Status |
Status and Criteria | Endangered B1ab(iii)+2ab(iii) |
Assessment Date | 2020/06/20 |
Assessor(s) | A.G. Rebelo, D. Raimondo & N.A. Helme |
Justification | Serruria altiscapa is a restricted endemic to the Hottentot Holland Mountains in South Africa. It has an extent of occurrence (EOO) of 82 km², and an area of occupancy (AOO) of 32 km². Four subpopulations from three threat defined locations are declining due to ongoing habitat degradation from the spread of alien plant invasion and too infrequent fires which leads to seed predation. There are fewer than 2000 mature individuals in the population. This species therefore qualifies for listing as Endangered under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is known from Villiersdorp to Hottentots Holland Mountains, in the Western Cape Province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Kogelberg Sandstone Fynbos, Hawequas Sandstone Fynbos |
Description | It occurs on south-facing sandstone slopes, occurring at altitudes between 700 and 1250 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 germinate following fire. It is pollinated by insects. |
Threats |
| Invasive alien pine and hakea species are a threat to this species throughout its range and is causing slow but ongoing decline to habitat quality and the number of mature individuals. Long intervals between fires over 20 years in some cases is a threat for three of the four subpopulations, moribund vegetation due to lack of burning results in high numbers of rodents that predate on flower heads thereby reducing seed set. |
Population |
This species is known from four subpopulations over a 24 km long range.
The first subpopulation occurs on Blokkop, the peak north west of the town of Villiersdorp. There are several hundred plants, mostly in a single patch, but with outliers over a 1.8 km range, the population has been monitored between 1993 and 2019 and is stable. This subpopulation burned in 1997, 2004, 2012 and 2016. Being a species that matures quickly, short fire return intervals are not likely to be a serious threat.
The second small subpopulation occurs at Pofaddernek, there were only four plants recorded here in 2002 and is likely to still be small as it has experienced long intervals between fires with only two fires in the past 40 years, one in 1985 and one in 2010.
The third subpopulation occurs in Boegoekloof along the Boland Hiking Trail. Several hundred plants occurred here over a 1 km zone between 1996 and 2002. This subpopulation has not been surveyed again since 2002 which is surprising as it is an easily accessible subpopulation, there may be decline taking place. It has experienced long intervals between fires with only two fires in the past 40 years one in 1983 and one in 2009.
The last known subpopulation occurs at Nuweberg where between 10 and 100 plants were recorded over a 500 m zone in 1996. This subpopulation occurs about 2.8 km south of the Boegoekloof subpopulation and is on the edge of a former pine plantation. The plantations have not been replanted since 2005, however no surveys have been conducted so it is unknown if the subpopulation remains extant or if there has been any recovery in the pine plantation from potential soil seedbanks. The former plantation has high densities of invasive alien plants which are now causing ongoing habitat degradation to this subpopulation. Lack of fire is also a concern with only two burns taking place in the past 40 years, one in 1988 and the other in 2009.
The population is suspected to be steadily declining due to ongoing spread of invasive alien plant species throughout its range.
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Population trend | Decreasing |
Conservation |
| It is protected in Hottentot’s Holland and Theewaters nature reserves. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Serruria altiscapa Rourke | EN B1ac(iv)+2ac(iv) | Raimondo et al. (2009) | | Serruria altiscapa Rourke | Vulnerable | 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.
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.
Rourke, J.P. 1994. Three new species of Serruria (Proteaceae) from the southwestern Cape. Bothalia 24(1):1-7.
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Citation |
| Rebelo, A.G., Raimondo, D. & Helme, N.A. 2020. Serruria altiscapa Rourke. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14 |
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