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Scientific Name | Geissorhiza eurystigma L.Bolus |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
Synonyms | Geissorhiza mathewsii L.Bolus var. eurystigma (L.Bolus) R.C.Foster, Geissorhiza monantha Sweet, Geissorhiza rochensis Ker Gawl. (in part), Geissorhiza rochensis Ker Gawl. var. spithamaea (Ker Gawl.) Baker |
Common Names | Wine-Cup (e) |
National Status |
Status and Criteria | Endangered B1ab(iii,v)+2ab(iii,v); C2a(i) |
Assessment Date | 2021/10/12 |
Assessor(s) | L. von Staden & T. Patel |
Justification | This species has an extent of occurrence (EOO) of 389 km², and an area of occupancy (AOO) of 76 km². It is known from thirteen extant locations. The population is severely fragmented and estimated to number fewer than 2500 mature individuals, with no subpopulation recorded to have more than 250 mature individuals. It continues to decline due to ongoing habitat degradation and competition from alien invasive plants. It is therefore listed as Endangered under criteria B and C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | It is restricted to the southwestern parts of the Western Cape province, South Africa, where it occurs mostly around Darling and Mamre, and extends south to Kalabaskraal and Malmesbury. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Atlantis Sand Fynbos, Swartland Granite Renosterveld |
Description | It grows in moist places in renosterveld, and in ecotones with sand plain fynbos. |
Threats |
| This species has lost 44% of its habitat (calculated using landcover data in GIS) to crop cultivation, and it now remains in small, isolated remnants of renosterveld. Although there is limited ongoing loss of habitat, remaining fragments continue to be degraded due to heavy overgrazing - most of the small remnants where this species persists are overstocked with livestock and are also impacted by dense infestations of alien invasive plants. The largest subpopulation occurs at Riverlands Nature Reserve that was cleared of alien invasive plants, but there has been extensive regrowth of invasives following fire and the site requires ongoing clearing efforts. |
Population |
The population is estimated to consist of fewer than 2500 mature individuals, with the majority of subpopulations (14 of the 15 known) being small (fewer than 100 mature individuals) and occurring on isolated remnants of renosterveld vegetation. There is only one large subpopulation that remains at Riverlands Nature Reserve. The population is therefore considered to be severely fragmented. It is declining due to ongoing habitat degradation and competition from alien invasive plants.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza eurystigma L.Bolus | CR B1ab(i,ii,iii,iv,iv) | 2012.1 | | Geissorhiza eurystigma L.Bolus | CR B1ab(i,ii,iii,iv,iv) | Raimondo et al. (2009) | | Geissorhiza eurystigma L.Bolus | Vulnerable | Hilton-Taylor (1996) | | Geissorhiza mathewsii L.Bolus var. eurystigma (L.Bolus) R.C.Foster | Vulnerable | 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 |
| von Staden, L. & Patel, T. 2021. Geissorhiza eurystigma L.Bolus. National Assessment: Red List of South African Plants version . Accessed on 2024/09/08 |
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