Drip Disa

Taxonomy
Scientific Name
Disa longicornu L.f.
Higher Classification
Monocotyledons
Family
ORCHIDACEAE
Synonyms
Disa longicornis Thunb.
Common Names
Bloumoederkappie (a), Disa (a), Drip Disa (e)
National Status
Status and Criteria
Endangered B1ab(v)+2ab(v)
Assessment Date
2022/07/07
Assessor(s)
N.N. Mhlongo, L. von Staden, E.G.H. Oliver & D. Raimondo
Justification
This species has a limited distribution range with an extent of occurrence (EOO) of 313 km² and an area of occupancy (AOO) of 44 km². It is known from three locations, comprising very small subpopulations, and the population is declining due to over-collecting and picking. Therefore, it qualifies as Endangered under criterion B.
Distribution
Endemism
South African endemic
Provincial distribution
Western Cape
Range
This species is endemic to the Western Cape Province of South Africa, where it is found in the Cape Peninsula and Jonkershoek Mountains.
Habitat and Ecology
Major system
Terrestrial
Major habitats
Peninsula Sandstone Fynbos, Kogelberg Sandstone Fynbos, Peninsula Granite Fynbos, Cape Flats Sand Fynbos
Description
It occurs in partly shaded, moist, south-facing rock ledges and cliffs, near waterfalls or other permanent water sources, 600-1000 m.
Threats
This attractive orchid, with its large conspicuous blue flowers, is threatened by over-collecting and picking, despite its montane habitat. Both mountains on which it occurs are crisscrossed by highly frequented hiking trails (often leading up the gorges where this orchid grows), and according to E.G.H. Oliver, who worked in herbaria in Cape Town and Stellenbosch for many years, 'everyone who sees it collects it.' As subpopulations are generally quite small, over-collecting is causing a decline in population numbers.
Population

Some collections indicate only single plants, but can also be locally common (W.R. Liltved, pers. comm.) According to Linder (1981), subpopulations tend to be quite small.


Population trend
Decreasing
Notes
Flowering annually in December and January and is not fire dependent.
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Disa longicornu L.f.VU B1ab(v)Raimondo et al. (2009)
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.


Liltved, W.R. and Johnson, S.D. Unpublished. The Cape Orchids - Wild orchids of the Cape Floral Kingdom.


Linder, H.P. 1981. Taxonomic studies in the Disinae. III. A revision of Disa Berg. excluding sect. Micranthae Lindl. Contributions from the Bolus Herbarium 9:1-370.


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.


Citation
Mhlongo, N.N., von Staden, L., Oliver, E.G.H. & Raimondo, D. 2022. Disa longicornu L.f. National Assessment: Red List of South African Plants version . Accessed on 2024/07/18

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Distribution map

© C. Merry

© C. Merry

© C. Merry

© C. Paterson-Jones

© H. Stärker


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