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Scientific Name | Disa cernua (Thunb.) Sw. |
Higher Classification | Monocotyledons |
Family | ORCHIDACEAE |
Synonyms | Disa prasinata Ker Gawl., Monadenia cernua (Thunb.) T.Durand & Schinz, Monadenia inflata Sond., Monadenia prasinata (Ker Gawl.) Lindl., Satyrium cernuum Thunb. |
National Status |
Status and Criteria | Vulnerable B2ab(ii,iii,iv,v) |
Assessment Date | 2012/09/11 |
Assessor(s) | L. von Staden, W.R. Liltved & H. Kurzweil |
Justification | This lowland species is specific to a very limited habitat and has an AOO<2000 km². Known from nine locations it is experiencing severe ongoing habitat loss due to coastal development, crop cultivation, alien plant invasion and lack of fire as a result of habitat fragmentation. This species is dependant on fire for flowering. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Eastern Cape, Western Cape |
Range | Cape Peninsula to Humansdorp. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Overberg Dune Strandveld, Tsitsikamma Sandstone Fynbos, Agulhas Limestone Fynbos, Agulhas Sand Fynbos, Hangklip Sand Fynbos, Cape Flats Sand Fynbos, Knysna Sand Fynbos |
Description | Sodden marsh environments on peaty soil derived from a combination of blackened organic material and Table Mountain Sandstone derived soils, below 300 m. |
Threats |
| Wetland ecosystems that form the habitat of this species are extremely vulnerable to disturbance and invasion by alien species. Declines in habitat quality of localities where this species occurs are continually observed on the south coast, from George to Humansdorp. One site on the West Coast will be lost to development in the near future. Remaining fragmented habitats supporting populations are not frequently subjected to fire. Healthy populations remain only at three sites (Cape Point, Betty's Bay and Groot Hagelkraal), of which only one (Cape Point) is formally protected. |
Population |
Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Disa cernua (Thunb.) Sw. | VU B2ab(ii,iii,iv,v) | Raimondo et al. (2009) | | Disa cernua (Thunb.) Sw. | Lower Risk - Near Threatened | Victor (2002) | |
Bibliography |
Liltved, W.R. and Johnson, S.D. Unpublished.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. & Kurzweil, H. 2012. Disa cernua (Thunb.) Sw. National Assessment: Red List of South African Plants version . Accessed on 2025/05/20 |
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