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Scientific Name | Geissorhiza imbricata (D.Delaroche) Ker Gawl. subsp. bicolor (Thunb.) Goldblatt |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
Synonyms | Geissorhiza bicolor (Thunb.) N.E.Br., Geissorhiza bicolor (Thunb.) N.E.Br. var. bicolor, Geissorhiza bicolor (Thunb.) N.E.Br. var. macowanii R.C.Foster, Geissorhiza imbricata (D.Delaroche) Ker Gawl. var. concolor Baker, Geissorhiza rubicunda R.C.Foster |
National Status |
Status and Criteria | Near Threatened B1b(ii,iii,iv,v)+2b(ii,iii,iv,v) |
Assessment Date | 2021/10/14 |
Assessor(s) | P. Goldblatt, D. Raimondo & T. Patel |
Justification | This taxon has an extent of occurrence (EOO) of 13 610 km² and an area of occupancy (AOO) of 148 km². It is known from at least 30 extant locations. Due to crop cultivation, urban development, and alien plant invasion, the population is declining. Therefore, it is classified as Near Threatened, nearly meeting the criteria B for listing as Vulnerable. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This taxon is found in the Western Cape Province of South Africa, extending from the Olifants River Valley and Porterville to the Cape Flats. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Peninsula Sandstone Fynbos, Breede Shale Fynbos, Boland Granite Fynbos, Cape Flats Sand Fynbos, Swartland Alluvium Fynbos, Breede Alluvium Fynbos |
Description | It occurs in wet, poorly drained flats and marshes or stream sides. |
Threats |
| About 68% of this species' habitat has been irreversibly modified (calculated using land cover data in GIS). The main causes are agriculture (crop fields) and urban expansion, with the majority of this loss occurring in the past. Urban expansion in various locations has led to the loss of subpopulations, including those in the Cape Flats, Wolseley, and Stellenbosch areas. Additionally, the species faces threat from invasive alien plants. |
Population |
No quantitative population data are available for this taxon. There are at least 30 known subpopulations. The population is declining, and the remaining subpopulations are under threat.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza imbricata (D.Delaroche) Ker Gawl. subsp. bicolor (Thunb.) Goldblatt | NT B1ab(ii,iii,iv,v) | Raimondo et al. (2009) | | Geissorhiza imbricata (D.Delaroche) Ker Gawl. subsp. bicolor (Thunb.) Goldblatt | Not Threatened | Hilton-Taylor (1996) | | Geissorhiza rubicunda R.C.Foster | Uncertain | 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. 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. & Patel, T. 2021. Geissorhiza imbricata (D.Delaroche) Ker Gawl. subsp. bicolor (Thunb.) Goldblatt. National Assessment: Red List of South African Plants version . Accessed on 2024/09/08 |
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