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Scientific Name | Conophytum chrisolum S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A3d; B1ab(iii)+2ab(iii) |
Assessment Date | 2021/11/17 |
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 succulent is endemic to the Northern Cape province of South Africa where it is only recorded from a single locality with an extent of occurrence (EOO) and area of occupancy (AOO) of 4 km². The dwarf succulents that comprise this genus have been increasingly targeted by illegal collection in recent years and the vast majority of species are in high demand by collectors. Whilst there is no evidence of illegal collection at the time of this submission, closely related species, including some from the immediate area, have been illegally removed from habitat with a dramatic increase in the number of species and volume of plants targeted since 2019. The threat of illegal collection is therefore regarded as very high for this particular species. The small population size and single location means that a complete decline of up to 100% of the population is likely within the next 10 years. The single location is on farmland and damage as a result of trampling by livestock is also possible. The single location and inability to disperse also makes the species very susceptible to the deleterious effects of climate change. Loss of vegetation cover has been observed at this site via Landsat imagery between 1984 and 2018 and is used to infer that the habitat quality is already in decline. It therefore qualifies as Critically Endangered under criteria A3 and B1+2. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to a small part of the Northern Cape province of South Africa where it is only found in a single location with a severely restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Heuweltjieveld |
Description | This species is known from a severely range restricted single location in the Succulent Karoo biome (Namaqualand Hardeveld Bioregion). The very small single headed (leaved) plants are found on flat areas of quartz grit and can be very cryptic. This species has a generation length of 20 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 threatened by illegal collection for the international trade in ornamental succulents. This is likely to increase in future as there has been a dramatic increase in the number of species and volume of plants targeted since 2019. The single location makes the small population very susceptible to rapid declines as a result of illegal collection.
Anthropogenic climate change is a long-term threat to this species. Loss of vegetation cover has been observed at this site via Landsat imagery between 1984 and 2018 and is used to infer that the habitat quality is already in decline. 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. The single location is on farmland and damage as a result of trampling by livestock is possible. |
Population |
This species is one of the smallest in the genus and is very cryptic in habitat. Fewer than 1,000 mature individuals are thought to be present in the wild. There is no evidence of illegal collection of this species, and recent fieldwork showed no evidence of collection. However, given extended drought from 2016 to present day the population may well be declining.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum chrisolum S.A.Hammer | CR B1ab(v)+2ab(v) | 2020.1 | | Conophytum chrisolum S.A.Hammer | VU D1+2 | 2017.1 | | Conophytum chrisolum S.A.Hammer | Critically Rare | Raimondo et al. (2009) | |
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).
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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 chrisolum S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2025/05/23 |
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