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Scientific Name | Geissorhiza tulbaghensis F.Bolus |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Endangered B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v) |
Assessment Date | 2012/10/22 |
Assessor(s) | I. Ebrahim, D. Raimondo & R.C. Turner |
Justification | EOO 291 km², seven small, severely fragmented subpopulations remain, mostly on road verges and in remnant patches of renosterveld. It has lost extensive habitat to wheat and vineyard expansion. We suspect that there are fewer than 2500 mature individuals extant. Declining due to alien plant invasion, pesticide spraying and agricultural and urban expansion. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | Porterville to Wellington. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Swartland Shale Renosterveld, Breede Shale Renosterveld, Breede Shale Fynbos, Swartland Alluvium Fynbos, Breede Alluvium Fynbos |
Description | Stony clay flats. |
Threats |
| Agricultural transformation for wheat and vineyard farming has caused the loss of three subpopulations known from herbarium records. One subpopulation in the Tulbagh valley is likely to be ploughed in the near future (landowner pers. comm. with I. Ebrahim 2005). Half of the subpopulations are being impacted by alien grass invasion. There is also loss of pollinators due to pesticide spraying, two subpopulations are adjacent to farmlands and volunteers of the Custodians of Rare and Endangered Wildflowers (CREW) Programme have documented a decline in numbers of individuals due to pesticide spraying. |
Population |
Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza tulbaghensis F.Bolus | EN B1ab(ii,iii,iv,v) | Raimondo et al. (2009) | |
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. 2000. Cape Plants: A conspectus of the Cape Flora of South Africa. Strelitzia 9. National Botanical Institute, Cape Town.
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 |
| Ebrahim, I., Raimondo, D. & Turner, R.C. 2012. Geissorhiza tulbaghensis F.Bolus. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2023/12/01 |
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