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Scientific Name | Ixia acaulis Goldblatt & J.C.Manning |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Endangered B1ab(ii,iii,v)+2ab(ii,iii,v) |
Assessment Date | 2020/11/24 |
Assessor(s) | N.A. Helme & L. von Staden |
Justification | Ixia acaulis has an extent of occurrence (EOO) of 35 km², and an area of occupancy (AOO) of less than 20 km². There are currently limestone prospecting applications on all three properties where this species is known to occur, and habitat loss to prospecting and mining activities is likely to cause a continuing decline. It is therefore listed as Endangered under criterion B. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is endemic to South Africa, and is found in Knersvlakte. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Knersvlakte Quartz Vygieveld, Knersvlakte Dolomite Vygieveld, Central Knersvlakte Vygieveld |
Description | It occurs in succulent karoo shrubland, in rock crevices or wedged between boulders on limestone ridges. |
Threats |
| About 1-2% of this species' habitat has already been transformed due to limestone quarrying about 10 years ago. There are currently prospecting applications for all three properties on which this species is known to occur, and habitat loss to open cast limestone mining is an ongoing threat. |
Population |
About 1-2% of this species' limestone habitat was quarried about 10 years ago, but impact on the population was probably small. Most subpopulations are small, consisting of around 50 plants, but one large subpopulation of more than 1500 plants is also known.
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Population trend | Decreasing |
Notes |
| This species flowers unusually early and is restricted to a highly specialized habitat (Goldblatt and Manning 1993). |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Ixia acaulis Goldblatt & J.C.Manning | VU D2 | Raimondo et al. (2009) | | Ixia acaulis Goldblatt & J.C.Manning | Rare | Hilton-Taylor (1996) | |
Bibliography |
De Vos, M.P. 1999. Ixia. In: O.A. Leistner (ed). Flora of Southern Africa 7 Iridaceae Part 2: Ixioideae, Fascicle 1: Ixieae:3-87. National Botanical Institute, Pretoria.
Goldblatt, P. and manning, J.C. 1993. Ixia acaulis, a new acaulescent species of Iridaceae : Ixioideae from the Knersvlakte, Namaqualand, South Africa. Novon 3(2):148-153.
Goldblatt, P. and Manning, J.C. 2011. Systematics of the southern African genus Ixia (Iridaceae). 3. Sections Hyalis and Morphixia. Bothalia 41(1):83-134.
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 |
| Helme, N.A. & von Staden, L. 2020. Ixia acaulis Goldblatt & J.C.Manning. National Assessment: Red List of South African Plants version . Accessed on 2025/05/01 |
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