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Scientific Name | Conophytum burgeri L.Bolus |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A4d; B1ab(iii,v)+2ab(iii,v) |
Assessment Date | 2021/11/16 |
Assessor(s) | A.J. Young, P.G. Desmet, I. Ebrahim, D. Guo, A. Harrower, L. Jabar, L. Knoetze, C. Rodgerson, P.C.V. Van Wyk & N.N. Mhlongo |
Justification | This dwarf succulent is endemic to the Northern Cape province of South Africa where it only recorded from a single location with an extent of occurrence (EOO) and area of occupancy (AOO) of 4 km². This species has been increasingly targeted by illegal collection in recent years and is in high demand by collectors. In 2021 mature individuals were removed from the only known locality for the illegal trade in succulents. The continued threat of illegal collection remains very high with the single location rendering the species highly susceptible to further rapid decline due to this activity and a decline of up to 100% is possible within 10 years. Climate change is also impacting the population although there is uncertainty of the response given the expected resilience of this species. It therefore qualifies as Critically Endangered under criteria A4 and B1+2. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to a small area of the Northern Cape province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Bushmanland Inselberg Shrubland |
Description | The plants are restricted to the Richtersveld bioregion of the Succulent Karoo biome. These cryptic plants have a semi-subterranean habit occurring in small, relatively flat, areas of quartz pebbles. This species has a generation length of 30 years. It is expected to be sensitive to the impacts of climate change as it does not disperse and while adapted to arid conditions, is dependent on limited seasonal rainfall. Species in the genus are sensitive to long periods of drought. Drought related mortality has been observed for other closely related taxa within the genus. |
Threats |
| This species has been subject to illegal collection of mature individuals for the international trade in ornamental succulents in 2020-21. This species has been highly sought after by collectors and is highly likely to remain so in future. The plants are severely range-restricted which coupled with the small population size renders them highly susceptible to a rapid decline in number through collection and there is a real possibility of extinction in habitat due to a single or series of poaching events.
Loss of vegetation cover as inferred from changes in Enhanced Vegetation Index (EVI) between 1984 and 2018 using Landsat data (Venter et al. 2020) has been experienced at the only known locality for this species.
Anthropogenic climate change is a long-term threat to this species. While it is not possible to model the response of this species to climate change due to its restricted distribution, the average loss to climate change for 14 more widely distributed Conophytum species occurring within the same region is used as an indication of likely impact to this species. Climate models for the likely emission scenarios where emissions stay at present day levels (RCP 2.6) (Hausfather and Peters 2020) and worst case scenarios where emissions continue to increase during the 21st century (RCP 8.5) indicate that there will be a loss of suitable bioclimatic envelope of between 32% and 81% by 2080 for Conophytum taxa within the region. However, as this taxon possesses certain morphological traits likely to afford resilience to xerophytic conditions it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to 12% based on the uncertainty of the response. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This species is only known from a single, range-restricted location where the number of mature individuals is probably fewer than 1,000 mature individuals. The population is declining due to illegal harvesting to supply the ornamental succulent plant trade.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum burgeri L.Bolus | EN D | Raimondo et al. (2009) | | Conophytum burgeri L.Bolus | VU D2 | Victor (2002) | | Conophytum burgeri L.Bolus | Vulnerable | Hilton-Taylor (1996) | |
Bibliography |
Hammer, S. 2002. Dumpling and his wife: New view of the genus Conophytum. EAE Creative Colour, Norwich.
Hammer, S.A. 1993. The genus Conophytum: A conograph. Succulent Plant Publications, Pretoria.
Hausfather, Z. and Peters, G.P. 2020. Emissions - the 'business as usual' story is misleading. Nature 577(618-620).
Opel, M.R. 2004. The rediscovery of Crassula alcicornis. Haseltonia 10:38-40.
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Citation |
| Young, A.J., Desmet, P.G., Ebrahim, I., Guo, D., Harrower, A., Jabar, L., Knoetze, L., Rodgerson, C., Van Wyk, P.C.V. & Mhlongo, N.N. 2021. Conophytum burgeri L.Bolus. National Assessment: Red List of South African Plants version . Accessed on 2025/05/20 |
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