|
Scientific Name | Serruria decumbens (Thunb.) R.Br. |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Synonyms | Serruria hyemalis Salisb. ex Knight |
Common Names | Peninsula Spiderhead (e) |
National Status |
Status and Criteria | Endangered B1ab(iii)+2ab(iii) |
Assessment Date | 2020/06/03 |
Assessor(s) | A.G. Rebelo, D. Raimondo & L. von Staden |
Justification | Serruria decumbens is a range-restricted endemic that occurs as isolated subpopulations along a 22 km range of mountains on the southern part of the Cape Peninsula in South Africa. It has an extent of occurrence (EOO) of 80 km² and an area of occupancy (AOO) of 60 km². Subpopulations at two threat based locations are declining as a result of too frequent fires. This species qualifies for listing as Endangered under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is known from the Cape Peninsula, in the Western Cape Province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Peninsula Sandstone Fynbos |
Description | It occurs in rocky places in sandstone fynbos, at 70-310 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 |
| This species is experiencing slow but ongoing degradation of its habitat due to too frequent fires, the Cape Point Section of this species' range where the majority of individuals are concentrated has experienced fires every 8 years for the past 25 years, a natural fire cycle would be between 15 and 20 year. Invasive alien acacias are also a threat especially to the subpopulation occurring at Rooikraans. |
Population |
It is known from between four and six extant subpopulations, the largest subpopulations occur within the Cape Point section of Table Mountain National Park with subpopulations numbering several hundred mature individuals occurring at Bonteberg and Olifantsbos. Smaller subpopulations of fewer than 100 plants occur within this same Cape Point location at Anvil Rocks, and Kommetieberg. Two small subpopulations occur on the mountains between Kommetjie and Simon’s Town, these are Rooikrans where the subpopulation consists of 20-30 plants and another on Manelkofkop which may be extinct as three plants were last recorded here in 2008. Other historically recorded subpopulations that have gone extinct are from Slangkop last recorded in 1950 and Tuinkop last recorded in 1971. The population is suspected to be declining slowly as a result of too frequent fires.
|
Population trend | Decreasing |
Conservation |
| All extant subpopulations are in the Cape of Good Hope Nature Reserve section of the Table Mountain National Park. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Serruria decumbens (Thunb.) R.Br. | EN B1ac(iv)+2ac(iv) | Raimondo et al. (2009) | | Serruria decumbens (Thunb.) R.Br. | 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.
Helme, N.A. and Trinder-Smith, T.H. 2006. The endemic flora of the Cape Peninsula, South Africa. South African Journal of Botany 72(2):205-210.
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.
|
Citation |
| Rebelo, A.G., Raimondo, D. & von Staden, L. 2020. Serruria decumbens (Thunb.) R.Br. National Assessment: Red List of South African Plants version . Accessed on 2025/06/04 |
Comment on this assessment
