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Scientific Name | Conophytum schlechteri Schwantes |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A4d; B1ab(v)+2ab(v) |
Assessment Date | 2021/12/07 |
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 species is endemic to the Northern Cape province of South Africa with an extent of occurrence (EOO) and area of occupancy (AOO) of 8 km2. The population is experiencing initial 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, including many taxa from the immediate area. The continued threat of illegal collection is therefore regarded as very high for this particular species. Given its single location and small population size of fewer than 500 mature individuals a complete decline of 100% of the population is likely within the next ten years. While climate change is also highly likely to impact this taxon the rapid declines to the population as a result of illegal collection means it 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 the Northern Cape province of South Africa where it is only found in a single location with a restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Southern Richtersveld Inselberg Shrubland |
Description | This succulent is endemic to Southern Richtersveld Inselberg Shrubland in the Richtersveld bioregion of the Succulent Karoo biome. It is localised to a single remote hill where it occupies (often mud-filled) rock depressions and crevices, often in full or partial shade.
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 threatened by illegal collection for the international trade in ornamental succulents. The plants are severely range-restricted which renders them highly susceptible to a rapid decline in number through collection or other adverse events.
Anthropogenic climate change is expected to pose 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 21 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 56% and 86% by 2080 for Conophytum taxa within the region. However, as this species occupies a very sheltered habitat it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to 36%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
There are no formal estimates of population size for this species but the number of mature individuals at the only known site is probably less than 500. The population is experiencing initial levels of decline due to the illegal collection of plants from habitat for the international trade in ornamental succulents.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum schlechteri Schwantes | Critically Rare | Raimondo et al. (2009) | | Conophytum schlechteri Schwantes | VU D2 | Victor (2002) | | Conophytum schlechteri Schwantes | Rare | 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).
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
Opel, M.R. 2004. The rediscovery of Crassula alcicornis. Haseltonia 10:38-40.
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.
Snijman, D.A. 2013. Plants of the Greater Cape Floristic Region 2: The extra Cape flora. Strelitzia 30. South African National Biodiversity Institute, Pretoria.
Victor, J.E. 2002. South Africa. In: J.S. Golding (ed), Southern African plant Red Data Lists. Southern African Botanical Diversity Network Report 14 (pp. 93-120), SABONET, Pretoria.
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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 schlechteri Schwantes. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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