Threatened Species Programme | SANBI Red List of South African Plants

Taxonomy

Scientific Name

Disa hallackii Rolfe

Higher Classification

Monocotyledons

Family

ORCHIDACEAE

Synonyms

Disa stokoei L.Bolus

National Status

Status and Criteria

Endangered C2a(i)

Assessment Date

2012/09/03

Assessor(s)

L. von Staden

Justification

A coastal lowland species that has lost most historical locations to urban expansion and crop cultivation. Known from between eight and 11 remaining subpopulations, the total population is estimated to number fewer than 1000 mature individuals and no subpopulation has more than 150 individuals. Declining due to ongoing habitat loss and degradation as a result of coastal development, alien plant invasion, grazing and road verge clearing.

Distribution

Endemism

South African endemic

Provincial distribution

Eastern Cape, Western Cape

Range

Cape Flats to Port Elizabeth.

Habitat and Ecology

Major system

Terrestrial

Major habitats

Overberg Dune Strandveld, Agulhas Limestone Fynbos, Garden Route Granite Fynbos, Hangklip Sand Fynbos, Cape Flats Sand Fynbos, Atlantis Sand Fynbos, Knysna Sand Fynbos, St Francis Dune Thicket, Hartenbos Dune Thicket, Goukamma Dune Thicket

Description

Lowland sandy flats, stabilised dunes and coastal rock promontories.

Threats

Threatened by ongoing habitat loss to urban expansion and coastal development, competition from alien invasive plants (these are also affecting some subpopulations within protected areas), grazing, and some subpopulations in small fragments are potentially affected by a lack of fire. Inappropriate management and clearing of road verges are also threatening a number of small subpopulations confined to roadside fragments of natural vegetation.

Population

Disa hallackii is widespread, but confined to a limited habitat on coastal lowlands. It was thought to be extremely rare, and at one stage was known from a single subpopulation near Mossel Bay (Linder 1999), but recently, a number of previously unrecorded subpopulations have been discovered. There are currently between eight and 11 remaining subpopulations. Survey data for nine of these indicate that subpopulations are very small, the largest consisting of around 150 mature individuals. Two subpopulations are protected in private nature reserves, and two other in a provincial nature reserve and a national park, but the rest are all threatened by ongoing habitat loss and degradation.

Population trend

Decreasing

Assessment History

Taxon assessed	Status and Criteria	Citation/Red List version
Disa hallackii Rolfe	EN C2a(i)	Raimondo et al. (2009)
Disa hallackii Rolfe	CR A1ceB1B2abcd	Victor (2002)
Disa hallackii Rolfe	Endangered	Hilton-Taylor (1996)
Disa stokoei L.Bolus	Endangered	Hall et al. (1980)

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.

Hall, A.V., De Winter, M., De Winter, B. and Van Oosterhout, S.A.M. 1980. Threatened plants of southern Africa. South African National Scienctific Programmes Report 45. CSIR, Pretoria.

Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.

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. 1999. Disa. In: H.P. Linder and H. Kurzweil (eds.), Orchids of southern Africa (pp. 187-288), 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.

Victor, J.E. and Dold, A.P. 2003. Threatened plants of the Albany Centre of Floristic Endemism, South Africa. South African Journal of Science 99:437-446.

Citation

von Staden, L. 2012. Disa hallackii Rolfe. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14

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