Taxonomy
Scientific Name
Brachystelma gerrardii Harv.
Higher Classification
Dicotyledons
Family
APOCYNACEAE
Synonyms
Brachystelma nigrum R.A.Dyer, Brachystelmaria gerrardii (Harv.) Schltr., Dichaelia gerrardii Harv., Lasiostelma gerrardii (Harv.) Schltr.
National Status
Status and Criteria
Endangered C2a(i)
Assessment Date
2007/05/08
Assessor(s)
D. Styles & L. von Staden
Justification
This widespread species is exceptionally rare, with subpopulations usually consisting of no more than 10 mature individuals. Currently recorded from 20 locations we conservatively estimate that the total population consists of fewer than 2500 mature individuals. It is severely threatened and declining due to habitat destruction in KwaZulu-Natal where the majority of the known subpopulations occur. Decline is as a result of urban and rural housing development, livestock overgrazing and a deleterious fire regime. Possibly also threatened by crop cultivation, afforestation, alien plant invasion and harvesting for food.
Distribution
Endemism
Not endemic to South Africa
Provincial distribution
KwaZulu-Natal, Limpopo, Mpumalanga
Range
KwaZulu-Natal, Waterberg, Wolkberg and Swaziland.
Habitat and Ecology
Major system
Terrestrial
Major habitats
KwaZulu-Natal Hinterland Thornveld, Moist Coast Hinterland Grassland, Dry Coast Hinterland Grassland, Waterberg-Magaliesberg Summit Sourveld, Woodbush Granite Grassland, Northern Escarpment Quartzite Sourveld, KaNgwane Montane Grassland, Paulpietersburg Moist Grassland, KwaZulu-Natal Coastal Belt Grassland
Description
Open grassland, 400-1800 m.
Threats
Populations in KwaZulu-Natal are threatened by habitat destruction as a result of urban and rural development, overgrazing and poor fire regimes (D. Styles pers. comm.) and the species is declining as a result of development in particular. According to Pooley (2005) the roots of this species are used as a food source. It is, however, not known whether this has a negative impact on the population. Particular threats to populations in Swaziland are not known, but grasslands are generally affected by agriculture, forestry plantations and invasive alien species. The species is probably not threatened in the Waterberg, as much of the area is conserved, while privately owned land is mostly used for low-impact game farming.
Population

Many authors have noted that this species is particularly rare (Dyer 1983, Alp 1999, Pooley 2005, D. Styles pers. comm.) According to David Styles, this species is very hard to find, and subpopulations are not readily found in suitable habitat. It usually occurs solitary or in groups of less than five individuals. The largest known subpopulation only has about 40-50 mature individuals. David estimates that there are probably no more than 500 mature individuals in southern KwaZulu-Natal.


Population trend
Decreasing
Notes
There are two 'forms' or ecotypes of this species - in KwaZulu-Natal the flowers are metallic blue-green, while further north they are dark green-black. The black form is probably not as threatened as the green form (D. Styles, pers. comm.).
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Brachystelma gerrardii Harv.EN C2a(i)Raimondo et al. (2009)
Brachystelma gerrardii Harv.Lower Risk - Least Concern Scott-Shaw (1999)
Bibliography

Alp, P.R. 1999. A note on Brachystelma gerrardii Harv. Asklepios 77:15.


Dyer, R.A. 1980. Brachystelma, Ceropegia and Riocreuxia. In: O.A. Leistner (ed). Flora of Southern Africa 27 Part 4:1-88. Botanical Research Institute, Pretoria.


Dyer, R.A. 1983. Ceropegia, Brachystelma and Riocreuxia in southern Africa. A.A. Balkema, Rotterdam, Netherlands.


Germishuizen, G., Meyer, N.L., Steenkamp, Y. and Keith, M. (eds). 2006. A checklist of South African plants. Southern African Botanical Diversity Network Report 41 SABONET, Pretoria.


Gordon-Gray, K.D. 1974. Brachystelma gerrardii. Flowering Plants of Africa 43(1-2):t.1686.


Pooley, E. 2005. A field guide to wild flowers of KwaZulu-Natal and the Eastern Region. Natal Flora Publications Trust, Durban.


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.


Scott-Shaw, C.R. 1999. Rare and threatened plants of KwaZulu-Natal and neighbouring regions. KwaZulu-Natal Nature Conservation Service, Pietermaritzburg.


Citation
Styles, D. & von Staden, L. 2007. Brachystelma gerrardii Harv. National Assessment: Red List of South African Plants version . Accessed on 2024/04/17

Comment on this assessment Comment on this assessment
Distribution map

© R. Boon

© R. Boon

© S. Parbhoo

© D. Styles

© D. Styles

© D. Styles

© D. Styles

© D. Styles


Search for images of Brachystelma gerrardii on iNaturalist