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Scientific Name | Leucadendron coriaceum E.Phillips & Hutch. |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Common Names | Rosette Conebush (e) |
National Status |
Status and Criteria | Endangered A2c; B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v); C1 |
Assessment Date | 2020/05/20 |
Assessor(s) | A.G. Rebelo, H. Mtshali & L. von Staden |
Justification | Leucadendron coriaceum is endemic to the Overberg Region of South Africa and has an extent of occurrence (EOO) of 3318-3626 km², and an area of occupancy (AOO) of 45 km². A population reduction of 70-80% is estimated based on an 86% loss of habitat, mainly to crop cultivation, in the past two generations (200 years). The majority of remaining subpopulations are severely fragmented and continue to decline due to ongoing habitat loss and fragmentation, skewed sex ratios in small fragments, recruitment failure, herbicide drift from adjacent crop fields, overgrazing, and increasing densities of alien invasive plants that outcompete native species. Decline is predicted to continue as farmers are highly reluctant to burn vegetation between crop fields. The populations consists of fewer than 2500 mature individuals. It therefore qualifies as Endangered under criteria A, B and C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is endemic to southern Cape Overberg region in the Western Cape Province of South Africa, where it occurs from Napier to Riversdale. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Eastern Ruens Shale Renosterveld, Central Ruens Shale Renosterveld, Western Ruens Shale Renosterveld, Ruens Silcrete Renosterveld, Potberg Ferricrete Fynbos |
Description | A renosterveld and renosterveld-ecotone species usually associated with silcrete and pallid zone clays. It is a long-lived, and survives fires by resprouting from underground boles or rootstocks and thus has a generation length that exceeds 100 years. Wind-dispersed seeds are released after ripening, and stored in surface leaf-litter. It is dioecious, with insect-pollinated male and female flowers occurring on separate plants. |
Threats |
| About 86% of this species' habitat is irreversibly modified, and loss continues, with 13% loss recorded between 1990 and 2014. Leucadendron coriaceum has become rare due to habitat loss to expanding cereals and pasture fields.
The remnant fragments of vegetation between crop fields where this species occurs are threatened by inappropriate fire management and degradation by livestock overgrazing, and herbicide drift from adjacent crop fields. Most of its habitat is also infested with alien invasive plants, that are outcompeting native species.
Recruitment has not been observed. Subpopulations are mildly to strongly biased to male plants. |
Population |
This species is currently known from 21 subpopulations, all but one subpopulation, the Potberg subpopulation in De Hoop Nature Reserve, occur in isolated remnants between cereal fields and over 50% of the population occurs in small isolated subpopulations. A total of 37% of historically recorded subpopulations based on herbarium specimens have gone extinct. One of these is the Nova subpopulations from south of Garcia’s Pass which was last recorded in 1963 and noted to be a large subpopulations. Around 50% of remaining subpopulations consist of fewer than 10 plants. The Potberg subpopulation was recorded between 1995 and 2002 to be extensive and between 200 and 500 individuals are suspected to still occur here. The following subpopulations have more than 10 plants but all have fewer than 200 individuals Plaatjieskraal; Leeuwenrivier; Goereesoe; Brakkefontein Farm and Rooikop. The overall populations consists of fewer than 2500 plants and ongoing decline is taking place as a result of habitat degradation in small fragments. The majority of the species habitat has been lost in the past two generations, as large scale habitat conversion started in 1945 when mechanised ploughing became possible. The population is suspected to have experienced between 70 and 80% decline within the past two generations based on 86% loss of suitable habitat.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Leucadendron coriaceum E.Phillips & Hutch. | EN A2c; B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v) | Raimondo et al. (2009) | | Leucadendron coriaceum E.Phillips & Hutch. | Endangered | Hilton-Taylor (1996) | | Leucadendron coriaceum E.Phillips & Hutch. | 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.
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Citation |
| Rebelo, A.G., Mtshali, H. & von Staden, L. 2020. Leucadendron coriaceum E.Phillips & Hutch. National Assessment: Red List of South African Plants version . Accessed on 2024/10/08 |
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