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Scientific Name | Aristea nigrescens J.C.Manning & Goldblatt |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Endangered B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v) |
Assessment Date | 2021/02/23 |
Assessor(s) | D. Raimondo & R. Koopman |
Justification | This highly local endemic, with an extent of occurrence (EOO) of 28 km², and an area of occupancy (AOO) of less than 28 km², is known from three locations that continue to decline due to deciduous fruit and vineyard expansion, lack of fire, and alien plant invasion. It is therefore listed as Endangered under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This local endemic has a limited distribution on the foot of the Waaihoek mountains in the Western Cape province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Breede Shale Renosterveld, Breede Shale Fynbos, Breede Alluvium Fynbos |
Description | It occurs on ferricrete or sandstone alluvium overlying Malmesbury shale in fynbos-renosterveld transition vegetation. |
Threats |
| Most of this species' habitat has been lost to deciduous fruit and vineyard cultivation, and there is ongoing habitat loss. As this species is dependent on fire for flowering, it is potentially vulnerable to inappropriate fire management, particularly too infrequent fires. Field observations noted alien invasive plants present in the habitat of some subpopulations. These could outcompete native species in future if left unmanaged. |
Population |
This species is known from a 12 km long range, with less than five subpopulations. Two subpopulations (Romansrivier and Waaihoek farms) are possibly extinct. There seems to be new vineyards on these sites according to Google Earth. Two other subpopulations at Weltevrede and Bosjemanskloof are safe, however alien plants were noted during the survey.
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Population trend | Decreasing |
Conservation |
| It is protected within the Romansrivier Contract Nature Reserve, established as part of CapeNature's Stewardship programme, this site was proclaimed in 2008. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Aristea nigrescens J.C.Manning & Goldblatt | EN B1ab(ii,iii,iv,v) | Raimondo et al. (2009) | |
Bibliography |
Goldblatt, P. and Manning, J.C. 2020. Iridaceae of southern Africa. Strelitzia 42. South African National Biodiversity Institute, Pretoria.
Manning, J.C. and Goldblatt, P. 2007. Iridaceae: Aristea nigrescens (subgenus Pseudaristea), a new species from the Western Cape, South Africa with a novel strategy for pollinator attraction. Bothalia 37(2):189-192.
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 |
| Raimondo, D. & Koopman, R. 2021. Aristea nigrescens J.C.Manning & Goldblatt. National Assessment: Red List of South African Plants version . Accessed on 2025/05/24 |
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