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Scientific Name | Geissorhiza humilis (Thunb.) Ker Gawl. |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Vulnerable B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v) |
Assessment Date | 2021/10/14 |
Assessor(s) | P. Goldblatt, R.C. Turner & T. Patel |
Justification | This species has an extent of occurrence (EOO) of 4401 km², and an area of occupancy (AOO) of 100 km². It is known from 10 locations. More than 50% of its habitat has been lost to crop cultivation and urban development. Almost 50% of recorded subpopulations have gone extinct. Remaining subpopulations are declining due to alien plant invasion and habitat loss to urban expansion. It is therefore listed as Vulnerable under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | A narrow endemic to the Western Cape province of South Africa, occurring from the Cape Peninsula to Stellenbosch, the Hex River Valley and Riverlands near Mamre Road. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Peninsula Sandstone Fynbos, South Hex Sandstone Fynbos, Hangklip Sand Fynbos, Cape Flats Sand Fynbos, Atlantis Sand Fynbos, Swartland Alluvium Fynbos, Breede Alluvium Fynbos |
Description | It occurs in fynbos, on coarse sandy ground, flowering well only after fire. |
Threats |
| This species has lost 56% of its habitat (calculated using landcover data in GIS). It is now largely extinct on the Cape Flats due to extensive habitat loss to urban expansion, agriculture and alien plant invasion, but subpopulations survive on the Cape Peninsula, where they are protected in the Table Mountain National Park. Outside protected areas however, this species continues to decline due to ongoing habitat loss to urban expansion and competition from alien invasive plants. |
Population |
The population has a decreasing trend. It is known from 10 locations across three subpopulations.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza humilis (Thunb.) Ker Gawl. | VU B1ab(iii,v) | Raimondo et al. (2009) | | Geissorhiza humilis (Thunb.) Ker Gawl. | Insufficiently Known | Hilton-Taylor (1996) | |
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.
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., Turner, R.C. & Patel, T. 2021. Geissorhiza humilis (Thunb.) Ker Gawl. National Assessment: Red List of South African Plants version . Accessed on 2024/09/14 |
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