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Scientific Name | Haworthia parksiana Poelln. |
Higher Classification | Monocotyledons |
Family | ASPHODELACEAE |
National Status |
Status and Criteria | Critically Endangered A2acd; B1ab(ii,iii,iv,v) |
Assessment Date | 2022/07/05 |
Assessor(s) | J.H. Vlok, D. Raimondo & N.N. Mhlongo |
Justification | A highly restricted endemic, known from three locations near the Great Brak River. It has a limited distribution range, with an extent of occurrence (EOO) of 32 km² and an area of occupancy (AOO) of 20 km². The population consists of fewer than 1000 plants, distributed among three small and severely fragmented subpopulations, each with fewer than 100 plants. Over the past 70 years (generation length 30 years), there has been an 80% population decline due to urban development, road construction, alien plant invasion, and illegal collection for the specialist succulent trade. Therefore, it qualifies as Critically Endangered under criteria A and B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species occurs in the Western Cape Province, where it is found near the Great Brak River. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Mossel Bay Shale Renosterveld, Garden Route Granite Fynbos |
Description | It grows in Renosterveld with karroid elements, in sandy soil, completely under the protection of small shrubs, well hidden in fallen leaf debris or among moss and lichen. |
Threats |
Subpopulations around Groot Brak have been lost due to urban development and alien encroachment over the past 70 years. There has also been a severe decline in the number of mature individuals due to plant collecting, resulting in an overall population decline of more than 80% in the past three generations. Collectors target this species as it is very slow growing, even in cultivation. One subpopulation was destroyed by the construction of the Southern Cape coastal road. Trampling by livestock and invasive alien species, such as black wattle, are also among the biggest threats to this species. |
Population |
A large proportion of the historical population, which consisted of more than 1000 individuals, has been lost due to illegal harvesting, urban development, and invasive alien species. The remaining subpopulations are severely fragmented due to crop farming, and none of the subpopulations have more than 100 plants. One of the locations is next to a farm with cattle, and trampling is a likely threat; the farm is also overgrown with black wattle.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | Haworthia parksiana Poelln. | CR A2acd; B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v) | Raimondo et al. (2009) | Haworthia parksiana Poelln. | Endangered | Hilton-Taylor (1996) | |
Bibliography |
Bayer, M.B. 1982. The new Haworthia handbook. National Botanical Gardens of South Africa.
Bayer, M.B. 1999. Haworthia Revisited: A revision of the genus. Umdaus Press, Hatfield.
Craib, C. 1990. Some rare Haworthias in South Africa. Aloe 27:23-26.
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.
Pilbeam, J.W. 1983. Haworthia and Astroloba, a collector's guide. B.T. Batsford Ltd., London.
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.
Scott, C.L. 1985. The genus Haworthia, a taxonomic revision. Aloe Books, Johannesburg.
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Citation |
Vlok, J.H., Raimondo, D. & Mhlongo, N.N. 2022. Haworthia parksiana Poelln. National Assessment: Red List of South African Plants version . Accessed on 2025/07/03 |