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Scientific Name | Leucadendron comosum (Thunb.) R.Br. subsp. homaeophyllum (Meisn.) I.Williams |
Higher Classification | Dicotyledons |
Family | PROTEACEAE |
Synonyms | Leucadendron aemulum R.Br. var. homaeophyllum Meisn. |
Common Names | Villiersdorp Ridge-cone Conebush (e) |
National Status |
Status and Criteria | Critically Endangered C2a(ii)b; D |
Assessment Date | 2019/08/13 |
Assessor(s) | A.G. Rebelo, D. Raimondo & L. von Staden |
Justification | An endemic to the mountains of the south western Cape South Africa. This species has an extent of occurrence (EOO) less than 50 km², and an area of occupancy of between 12 and 16 km². Three small, isolated subpopulations occur at two locations, with the possibility that one of the subpopulations has already gone extinct as result of wildflower harvesting. Extreme fluctuations is inferred from the fact that this species is a serotinous reseeder known to undergo density-dependent population fluctuations of one to three orders of magnitude in response to fire (Bond et al. 1995). There is ongoing decline in habitat quality due to alien plant invasion and inappropriate fire management. The entire population at present consists of fewer than 50 mature individuals. It therefore qualifies as Critically Endangered under criteria C and D. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This subspecies is endemic to Stettyns mountains in South Africa, above High Noon and Du Toit's Kloof Pass. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Hawequas Sandstone Fynbos, Boland Granite Fynbos |
Description | It occurs in sandstone fynbos at high altitude and granite fynbos at mid altitudes. Mature individuals are killed by fires, and only seeds survive. Wind-dispersed seeds are stored in fire-resistant inflorescences, and released after fires. It is dioecious, with insect-pollinated male and female flowers occurring on separate plants. |
Threats |
| This subspecies is threatened by harvesting for the cut flower industry with documented loss of the females from the population at Du Toit's Kloof as a result of harvesting. Invasive species of pine and hakea and too frequent fires are severe threats to both known locations. |
Population |
Three small subpopulations have been recorded in the past 20 years. The first at Du Toit's Kloof Pass consisted of only 10 plants in 1998 with only one female, all cones were harvested for the cut flower trade, and it is suspected that no seeds remained. No more plants have been seen at this site since 2002 and it may be extinct. A single herbarium collection exists from Aasvoelberg collected in the 1980s however despite atlasing taking place on this mountain range during the Protea Atlas project (1992 to 2002), no plants were recorded. The last subpopulation is from Bloukop where a single patch of 20 plants were last recorded in 2002 in an area of 20 m x 5 m.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Leucadendron comosum (Thunb.) R.Br. subsp. homaeophyllum (Meisn.) I.Williams | CR B1ab(i,ii,iii,iv,v)c(iv)+2ab(i,ii,iii,iv,v)c(iv); D | Raimondo et al. (2009) | | Leucadendron comosum (Thunb.) R.Br. subsp. homaeophyllum (Meisn.) I.Williams | Not Threatened | Hilton-Taylor (1996) | | Leucadendron comosum (Thunb.) R.Br. subsp. homaeophyllum (Meisn.) I.Williams | Extinct | Hall et al. (1980) | |
Bibliography |
Bond, W.J., Maze, K. and Desmet, P. 1995. Fire life histories and the seeds of chaos. Ecoscience 2(3):252-260.
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.
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. 2019. Leucadendron comosum (Thunb.) R.Br. subsp. homaeophyllum (Meisn.) I.Williams. National Assessment: Red List of South African Plants version . Accessed on 2025/05/09 |
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