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Scientific Name | Brunia trigyna (Schltr.) Class.-Bockh. & E.G.H.Oliv. |
Higher Classification | Dicotyledons |
Family | BRUNIACEAE |
Synonyms | Raspalia trigyna (Schltr.) Dummer |
Common Names | Pondo Ghost-bush (e), Pondoland Ghost-bush (e) |
National Status |
Status and Criteria | Critically Endangered B1ab(v)+2ab(v); C2a(i); D |
Assessment Date | 2018/09/27 |
Assessor(s) | A.T.D. Abbott, L. von Staden & J.E. Victor |
Justification | Brunia trigyna has been declining since the early 1900s due to habitat destruction, and by the 1960s reached critically low numbers. The recent discovery of one healthy breeding population brought hope that the species might recover, but ex-situ plants introduced near isolated wild individuals have yet to prove to be able to boost the reproductive output of these subpopulations. The single reproductively active sub-population of about 12 mature individuals is not protected and may still rapidly decline if any impacts on the habitat were to occur.
It has an extent of occurrence (EOO) of 100 km², and an area of occupancy (AOO) of less than 0.1 km². It occurs at three locations, and its subpopulations are severely fragmented. There are three remaining wild subpopulations, the largest consisting of 12 mature individuals, the other having only two and one plants respectively. The total population of mature individuals is 15. This species is therefore listed as Critically Endangered under criteria B and C. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Eastern Cape, KwaZulu-Natal |
Range | Brunia trigyna is endemic to South Africa, and was formerly distributed from Murchison district to Magwa Gorge, but now only known from Umtamvuna Nature Reserve and Mkambati. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Pondoland-Ugu Sandstone Coastal Sourveld |
Description | It occurs in Pondoland, grassland on sandstone, seasonally moist areas in open grassland along stream banks, generally in sites protected from fire, 350-450 m. |
Threats |
| Until a healthy sub-population was discovered in 2001, Brunia trigyna was thought to be rapidly declining towards extinction, mainly because of intrinsic factors. The population had reached critically low numbers, with only one or two individuals remaining per site, and in this obligate outcrossing species, seed set became impossible. Since the discovery of the healthy breeding population, seedlings were grown from cuttings and introduced at the sites where only one or two individuals remain, but in spite of this, these sub-populations do not show any signs of natural recruitment to date. The number of wild individuals is still critically low, but the discovery of the breeding population brings more hope that this species has a chance of survival.
Habitat destruction no doubt also played a role in the decline of this species. Grasslands around Murchison were all converted to sugarcane and streams are badly degraded - unlikely to provide the seepage conditions that this species appears to prefer. The large number of individuals observed in the early 1900s above the Magwa Gorge quite likely had to make way for tea estates (Arkell 1996).
The plant known from below the Magwa Falls between 1988 and 1995 may have died from old age, but pressures on the habitat cannot be ruled out. A Eucalyptus grove planted only a few metres away may have extracted too much water, drying up the moist habitat, or trampling by cattle may also have disturbed the water flow (Arkell 1996).
The only healthy sub-population occurs outside of a protected area, and is certainly not safe from destruction (T. Abbott pers. comm.). Wildfire is the main potential threat, as B. trigyna appear to be sensitive to fire, and tend to grow in sites protected from fire (Arkell 1996). |
Population |
There are three wild subpopulations: two plants in the Umtamvuna Nature Reserve, one plant in the Mkambati Nature Reserve, and 12 mature individuals outside the Mkambati Nature Reserve and about 12 juveniles and seedlings. Several introduced subpopulations exist at Mkambati, Umtamvuna, on a privately owned property near the Mkweni River, and another private property at Oribi Gorge. (T. Abbott pers. comm.).
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Population trend | Decreasing |
Conservation |
| Two wild plants and a number of introduced individuals are protected in the Umtamvuna Nature Reserve. An introduced subpopulation and one wild individual are protected in the Mkambati Nature Reserve. The only viable wild subpopulation is not protected at present. An ongoing ex-situ propagation project has produced a number of individuals that have been introduced at various sites in the Pondoland region (Abbott 2003, T. Abbott pers. comm.). |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Raspalia trigyna (Schltr.) Dummer | CR B1ab(v)+2ab(v); C2a(i); D | 2012.1 | | Raspalia trigyna (Schltr.) Dummer | CR B1ab(v)+2ab(v); C2a(i); D | Raimondo et al. (2009) | | Raspalia trigyna (Schltr.) Dummer | CR | Scott-Shaw (1999) | | Raspalia trigyna (Schltr.) Dummer | Endangered | Hilton-Taylor (1996) | |
Bibliography |
Abbott, A. 1988. The last days of Raspalia trigyna. Trees in South Africa 39:41-43.
Abbott, A. 1988. The return of Raspalia trigyna. Trees in South Africa 40:20-21.
Abbott, T. 1996. Woody plants of the Pondoland Centre: Raspalia trigyna - the ghost of the Pondoland Centre. Trees in South Africa 56:8-10.
Abbott, T. 2003. The story of the Pondoland Ghost Bush. http://www.safcei.org.za/wildcoast/raspalia_story.htm. Downloaded on 10-10-2007.
Abbott, T. 2006. The story of the Pondoland Centre. PlantLife 33&34:5-72.
Arkell, J. 1996. South Africa's rarest shrub lives! PlantLife 14:24.
Arkell, J. 1996. The quiet extinction of Raspalia trigyna. Plantlife 13:19-20.
Boon, R. 2010. Pooley's Trees of eastern South Africa. Flora and Fauna Publications Trust, Durban.
Claßen-Bockhoff, R., Oliver, E.G.H., Hall, A.V. and Quint, M. 2011. A new classification of the South African endemic family Bruniaceae based on molecular and morphological data. Taxon 60(4):1138-1155.
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
Pillans, N.S. 1947. A revision of Bruniaceae. Journal of South African Botany 13:121-206.
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.
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Citation |
| Abbott, A.T.D., von Staden, L. & Victor, J.E. 2018. Brunia trigyna (Schltr.) Class.-Bockh. & E.G.H.Oliv. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14 |
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