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Scientific Name | Conophytum brunneum S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A4d; B1ab(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 species of dwarf succulent is endemic to the Western Cape province of South Africa where it only recorded from a single locality with an extent of occurrence (EOO) and area of occupancy (AOO) of 16 km². The population is experiencing substantial levels of decline due to the illegal ornamental succulent plant trade, with collection likely to increase as there has been a dramatic increase in the number of species and volume of plants targeted since 2019. The continued threat of illegal collection is therefore regarded as very high for this particular species. Given its single location a complete decline of up to 100% of the population is possible within the next ten years. It therefore qualifies as Critically Endangered under criteria A4 and B1. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is only known from the Western Cape province of South Africa where it is found in a single location with a restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Southern Namaqualand Quartzite Klipkoppe Shrubland |
Description | This plant is endemic to the Succulent Karoo biome where it is found in the Namaqualand Hardeveld bioregion. The plants grow on a partially shaded, west-facing quartzitic or sandstone slopes. 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 is currently subject to illegal collection for the international trade in ornamental succulents. 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 with a real possibility of extinction in habitat due to a single adverse event. The only known location is close to human habitation.
Plants occur on land used for livestock grazing which is causing ongoing habitat degradation. 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 15 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 72% and 99% by 2080 for Conophytum taxa within the region. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
Plants occur in scattered clusters on hills across two adjacent farms. It is locally abundant across its range. A further subpopulation remains unconfirmed. A field survey in 2021 reported at least 4,000 mature individuals (SANBI field survey 2021). 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 brunneum S.A.Hammer | VU D2 | 2017.1 | | Conophytum brunneum S.A.Hammer | Least Concern | Raimondo et al. (2009) | |
Bibliography |
Hammer, S. 2002. Dumpling and his wife: New view of the genus Conophytum. EAE Creative Colour, Norwich.
Hartmann, H.E.K. 2002. Illustrated handbook of succulent plants: Aizoaceae A-E. Springer, Berlin.
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 brunneum S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2024/12/07 |
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