|
Scientific Name | Geissorhiza outeniquensis Goldblatt |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Near Threatened D2 |
Assessment Date | 2023/06/12 |
Assessor(s) | P. Goldblatt, D. Raimondo, R.C. Turner & T. Patel |
Justification | This is a localized species with an extent of occurrence (EOO) of 1739 km² and an area of occupancy (AOO) of 180 km². Plants at eight known locations are potentially threatened by alien plant invasion, water extraction and road construction. It is therefore listed as Near Threatened, almost meeting criteria D to be listed as Vulnerable. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | It is endemic to the Western Cape province of South Africa, and is restricted to the Outeniqua Mountains immediately around George. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | South Kammanassie Sandstone Fynbos, South Outeniqua Sandstone Fynbos |
Description | It occurs in moist, shady kloofs, along streams, waterfalls and wet banks in shade. |
Threats |
| The southern slopes of the Outeniqua Mountains have been extensively planted with timber plantations, and from these plantations, escaped pine seedlings have spread across large areas of the mountains. To the east of Cradock Pass, and on the Engelseberg are dense, unmanaged stands of alien invasive plants, that continue to spread. During field surveys, presence of alien invasive plants have been noted in this species' habitat on the Jonkersberg, Cradock Pass, as well as Montagu Pass. If these are also left unmanaged, they are likely to outcompete native species within a very short time. Alien invasive plants also reduce stream flow in mountain catchment areas, and dense invasions upstream could potentially negatively impact this moisture-dependent species. |
Population |
Surveys indicated that this species is common in suitable habitat in the Outeniqua Mountains north of George, with subpopulations numbering more than 1000 mature individuals. It is also likely to be much more common elsewhere in the Outeniqua Mountains, where it is currently known from only a few, scattered herbarium records. Although alien invasive plants are present within the habitat, the threat is currently still low, and the population is thought to be stable.
|
Population trend | Stable |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza outeniquensis Goldblatt | VU D2 | 2012.1 | | Geissorhiza outeniquensis Goldblatt | VU D2 | Raimondo et al. (2009) | | Geissorhiza outeniquensis Goldblatt | Rare | 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. 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.
|
Citation |
| Goldblatt, P., Raimondo, D., Turner, R.C. & Patel, T. 2023. Geissorhiza outeniquensis Goldblatt. National Assessment: Red List of South African Plants version . Accessed on 2024/09/08 |
Comment on this assessment
