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Scientific Name | Disa introrsa Kurzweil, Liltved & H.P.Linder |
Higher Classification | Monocotyledons |
Family | ORCHIDACEAE |
National Status |
Status and Criteria | Vulnerable D2 |
Assessment Date | 2017/04/13 |
Assessor(s) | L. von Staden, W.R. Liltved, E.G.H. Oliver & T.A. Oliver |
Justification | Disa introrsa is a rare and localized habitat specialist, with an extent of occurrence (EOO) of less than 10 km². It is known from two locations where it is potentially threatened by habitat loss to dam construction and agriculture. It is therefore listed as Vulnerable under criterion D. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species in endemic to South Africa, and is found in Southern Skurweberge in the Koue Bokkeveld. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Winterhoek Sandstone Fynbos |
Description | It occupies mountain slopes, near running water, 1000-1190 m. |
Threats |
| The small and localized population is potentially threatened by habitat loss to dam construction and expanding fruit orchards. There has been much recent expansion of agricultural development above Gydo Pass in recent years (N.A. Helme pers. comm.). |
Population |
There are two known subpopulations of Disa introrsa, occurring about 5 km apart. Both subpopulations are very small, the largest consisting of 20-30 plants and the other less than 10 plants. This species is a fire ephemeral, flowering only in the first summer after fires, and therefore highly likely to be overlooked, and a confident estimate of the population size cannot be made at present.
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Population trend | Stable |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Disa introrsa Kurzweil, Liltved & H.P.Linder | VU D2 | 2020.1 | | Disa introrsa Kurzweil, Liltved & H.P.Linder | Rare | Raimondo et al. (2009) | | Disa introrsa Kurzweil, Liltved & H.P.Linder | VU D2 | Victor (2002) | | Disa introrsa Kurzweil, Liltved & H.P.Linder | Rare | Hilton-Taylor (1997) | |
Bibliography |
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.
Hilton-Taylor, C. 1997. Red Data List of southern African plants. 2. Corrections and additions. Bothalia 27(2):195-209.
Kurzweil, H., Liltved, W.R. and Linder, H.P. 1997. Disa introrsa sp. nov. (Orchidaceae) from the Western Cape of South Africa, with notes on the phylogeny of Disa sect. Disella. Nordic Journal of Botany 17(4):353-260.
Liltved, W.R. and Johnson, S.D. Unpublished. The Cape Orchids - Wild orchids of the Cape Floral Kingdom.
Linder, H.P. and Kurzweil, H. 1999. Orchids of southern Africa. A.A. Balkema, Rotterdam.
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.
Victor, J.E. 2002. South Africa. In: J.S. Golding (ed), Southern African plant Red Data Lists. Southern African Botanical Diversity Network Report 14 (pp. 93-120), SABONET, Pretoria.
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Citation |
| von Staden, L., Liltved, W.R., Oliver, E.G.H. & Oliver, T.A. 2017. Disa introrsa Kurzweil, Liltved & H.P.Linder. National Assessment: Red List of South African Plants version . Accessed on 2024/09/15 |
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