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Scientific Name | Geissorhiza furva Ker Gawl. ex Baker |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Endangered B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v) |
Assessment Date | 2021/10/13 |
Assessor(s) | P. Goldblatt, D. Raimondo, R.C. Turner & T. Patel |
Justification | This species has an extent of occurrence (EOO) of 4546 km² and an area of occupancy (AOO) of 84 km². It is known from six extant locations, and the population is severely fragmented. Over the past century, it has lost over 50% of known subpopulations to wheat and vineyard cultivation. The remaining subpopulations are small and isolated. Declines are continuing due to the expansion of olive and vineyard cultivation, as well as alien plant invasion. Therefore, it is listed as Endangered under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | It is endemic to the western coastal lowlands of Western Cape, South Africa, extending from Mulder's Vlei near Stellenbosch to Elandsberg Nature Reserve. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Swartland Shale Renosterveld, Swartland Granite Renosterveld, Boland Granite Fynbos, Swartland Alluvium Fynbos, Breede Alluvium Fynbos |
Description | It occurs on stony or sandy flats and slopes at the foot of mountains that run north-south, parallel to the coast. |
Threats |
| This species has lost 76% of its habitat (calculated using landcover data in GIS). It faces severe threats and is locally extinct in many areas due to ongoing habitat loss to crop cultivation, particularly vineyards and olive farms. Subpopulations around Durbanville and Wellington are also under threat from habitat loss due to urban expansion, and several subpopulations are at risk due to invasive alien plants. |
Population |
It is known from six extant subpopulations, with isolation observed between them. Only three of the six extant subpopulations have detailed information available. Two are characterized as small subpopulations with less than 50 individuals, and one subpopulation was noted as locally frequent in the 1980s, though no specific information on its current population size is available. As a result, we suspect that at least 50% of the subpopulations are small and isolated. The population is considered to be severely fragmented and decreasing.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza furva Ker Gawl. ex Baker | EN B1ab(ii,iii,iv,v) | Raimondo et al. (2009) | | Geissorhiza furva Ker Gawl. ex Baker | Rare | Hilton-Taylor (1996) | | Geissorhiza furva Ker Gawl. ex Baker | Indeterminate | Hall et al. (1980) | |
Bibliography |
Goldblatt, P. 1985. Systematics of the southern African genus Geissorhiza (Iridaceae-Ixioideae). Annals of the Missouri Botanical Garden 72(2):277-447.
Goldblatt, P. and manning, J.C. 1995. New species of the southern African genus Geissorhiza (Iridaceae: Ixioideae). Novon 5(2):156-161.
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.
Goldblatt, P. and Manning, J.C. 2020. Iridaceae of southern Africa. Strelitzia 42. South African National Biodiversity Institute, Pretoria.
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.
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Citation |
| Goldblatt, P., Raimondo, D., Turner, R.C. & Patel, T. 2021. Geissorhiza furva Ker Gawl. ex Baker. National Assessment: Red List of South African Plants version . Accessed on 2024/09/08 |
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