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Scientific Name | Geissorhiza brehmii Eckl. ex Klatt |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
Synonyms | Geissorhiza teretifolia G.J.Lewis |
National Status |
Status and Criteria | Endangered B2ab(iii,v); C2a(i) |
Assessment Date | 2023/05/10 |
Assessor(s) | N.A. Helme & D. Raimondo |
Justification | This species has an extent of occurrence (EOO) of between 4944 and 19 668 km², and an area of occupancy (AOO) of between 32 and 48 km². This wetland specialist used to occur from the Cape Peninsula northwards to the Malmesbury district and eastwards to Caledon and Bredasdorp. It has lost 70% of known subpopulations to crop cultivation and urban development. The range in its EOO and AOO is due to uncertainty on whether subpopulations on the periphery of its range are still extant. As a wetland specific species its subpopulations are isolated from one another and monitoring data over the past 20 years note subpopulations to be small. The population is therefore considered severely fragmented. The total population has fewer than 2500 mature individuals and no subpopulation has been recorded to have more than 250 mature individuals. There is ongoing decline as a result of habitat degradation from eutrophication processes and the impact of invasive alien plants. This species therefore qualifies for listing as Endangered under criteria B and C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | It is endemic to South Africa, and is found from the Cape Peninsula to Malmesbury, Caledon and Bredasdorp in Western Cape. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Greyton Shale Fynbos, Boland Granite Fynbos, Breede Sand Fynbos, Agulhas Sand Fynbos, Hangklip Sand Fynbos, Cape Flats Sand Fynbos, Lourensford Alluvium Fynbos, Swartland Alluvium Fynbos, Breede Alluvium Fynbos |
Description | It occurs in sandy ground, either swampy or seasonally flooded or at the edge of pools. |
Threats |
| This species has lost 47% of its habitat (calculated using landcover data in GIS). It is threatened by ongoing habitat loss, fragmentation and degradation due to expanding crop cultivation and urban development, as well as competition from alien invasive plants. Its wetland habitat is also impacted by eutrophication. |
Population |
It is known from less than 10 subpopulations, and the population is declining. All subpopulations recorded in the past 20 years are small, many with only 10 mature individuals, only one subpopulation has been recorded to have 100 mature individuals. The total population is thus projected to be less than 2500 individuals and no subpopulation has been recorded to have more than 250 mature individuals.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza brehmii Eckl. ex Klatt | VU B1ab(i,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.
Goldblatt, P. and Manning, J.C. 2020. Iridaceae of southern Africa. Strelitzia 42. South African National Biodiversity 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 |
| Helme, N.A. & Raimondo, D. 2023. Geissorhiza brehmii Eckl. ex Klatt. National Assessment: Red List of South African Plants version . Accessed on 2024/09/14 |
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