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Scientific Name | Leucadendron thymifolium (Salisb. ex Knight) I.Williams |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Common Names | Malmesbury Conebush (e) |
National Status |
Status and Criteria | Endangered A2ace; B1ab(ii,iii,v)+2ab(ii,iii,v); C1 |
Assessment Date | 2020/04/22 |
Assessor(s) | A.G. Rebelo, D. Raimondo, L. von Staden & J. van der Merwe |
Justification | Leucadendron thymifolium is an endemic species to the Swartland region of the South Africa's Western Cape Province, it has an extent of occurrence (EOO) of between 403 and 462 km² and an area of occupancy (AOO) of 120 km². Most subpopulations are now confined to road verges and small remnant patches of vegetation as over 90% of this species' habitat has been transformed by urban and agricultural expansion and alien plant invasion. With more than 50% of the population found in small isolated remnants of vegetation, this species qualifies as severely fragmented. It continues to decline as a result of loss to invasive alien plants and lack of fire, monitoring of subpopulations shows that there has been more than 50% decline since 1985 (three generations), with between 20 and 30% of this decline taking place since 1995 (2 generations). It therefore qualifies for Endangered under criterion A, B, C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is endemic to the lowland areas of the Swartland in the Western Cape, South Africa, from Riebeeck Kasteel to Dassenberg, Klipheuwel and Blouberg. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Swartland Shale Renosterveld, Swartland Granite Renosterveld, Swartland Silcrete Renosterveld, Cape Flats Sand Fynbos, Atlantis Sand Fynbos |
Description | It is found in sandy or gravelly soils over clay. Appears to be able to survive in seasonally damp areas along road verges, provided that they are not mown or cleared. Able to recruit in the absence of fire. Mature individuals are killed by fires, and only seeds survive. Seeds are released after ripening, and is stored in surface leaf-litter. It is dioecious, with insect-pollinated male and female flowers occurring on separate plants. The generation length of this species is linked to the average fire return interval of between 15 and 20 years. |
Threats |
| A total of 71% of this species former habitat has been irreversibly transformed to the cultivation of cereals and to rural urban development and additional 20% has been severely infested with invasive alien plants. This species remains on small fragments of remnant natural vegetation and on road verges where it continues to decline as a result of alien plant invasions and inappropriate fire management either a lack of fire or too-infrequent fire. Furthermore there is ongoing loss to road verge clearing.
This species was assessed as Critically Endangered in 2004, however the 2004 assessment was based on modelled decline predicted to take place due to climate change. Predictions were made for 2025 in the year 2000. As of 2020 there has not be evidence of drought related death, hence this updated assessment focuses on the current status of severely fragmented subpopulations and a 50% decline in the population since 1985. |
Population |
Over 90% of this species’ habitat has been transformed for crop cultivation, urban development or severely infested by invasive alien plants. It now remains as small isolated stands mainly along road verges. The largest subpopulation is at Schoongezicht where there are around 1000 extant mature individuals. Smaller subpopulations of between 50 and 200 plants remain at Hunters Valley, Rondeberg; Munniks Dam; Klipheuwel RadioMaste and Kalabaskraal. There has been a more than 50% decline in the number of individuals at three of these subpopulation: Kalabaskraal, Klipheuwel and Rondeberg since 1995, mostly in response to lack of fire or poor recruitment following burns that have taken place. Two viable subpopulations that used to occur along the N7 highway have been lost to a recent large scale transport infrastructure upgrade. There are between 20 and 30 tiny stands of individuals (all less than 10 plants) that remain on road verges and in remnant vegetation between cultivated fields. Overall the population has declined by over 50% since 1985 and by between 20 and 30% since 1995. The largest subpopulation at Schoongezicht has recently come under protection as a Private Stewardship Nature Reserve.
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Population trend | Decreasing |
Conservation |
| A subpopulation occurs in the Klipheuwel Natural Heritage Site and in the Kalbaskraal Nature Reserve. |
Notes |
| Ex situ conservation is in place for this species, it is cultivated at Kirstenbosch Botanical Gardens, a subpopulations have been planted at Blouberg Nature Reserve, which is outside of this species historic range. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Leucadendron thymifolium (Salisb. ex Knight) I.Williams | CR A2c+3c+4c; B1b(i,ii,iii,iv,v)c(iv) | Raimondo et al. (2009) | | Leucadendron thymifolium (Salisb. ex Knight) I.Williams | Endangered | Hilton-Taylor (1996) | | Leucadendron thymifolium (Salisb. ex Knight) I.Williams | Endangered | 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.
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Citation |
| Rebelo, A.G., Raimondo, D., von Staden, L. & van der Merwe, J. 2020. Leucadendron thymifolium (Salisb. ex Knight) I.Williams. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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