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Scientific Name | Conophytum stephanii Schwantes subsp. helmutii (Lavis) S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum helmutii Lavis |
National Status |
Status and Criteria | Endangered A4cd |
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 |
Justification | This dwarf succulent is endemic to the Northern Cape province of South Africa with an extent of occurrence (EOO) of 4,416 km2 and area of occupancy (AOO) of 140 km2. The population is in decline due to illegal collection for the international trade in ornamental succulents since 2019. Illegal collection is likely to increase as there has been a dramatic increase in the number of species and volume of plants targeted since 2019 including many from the immediate area. The continued threat of illegal collection is therefore regarded as very high for this particular taxon. However, its relatively wide and scattered distribution is likely to limit the decline to between 50 and 60% of the population within the next three generations (90 years). Climate change is also impacting the population although there is uncertainty of the response given the expected resilience of this taxon. It therefore qualifies as Endangered under criterion A4. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This succulent is endemic to the Northern Cape province of South Africa, where it primarily occurs in the Richtersveld region. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Rosyntjieberg Succulent Shrubland, Umdaus Mountains Succulent Shrubland, Kosiesberg Succulent Shrubland, Namaqualand Klipkoppe Shrubland |
Description | This dwarf succulent is found in both the Succulent Karoo and Desert biomes, primarily within the Richtersveld and Gariep Desert bioregions but can also be found in the Namaqualand Hardeveld bioregion. The plants occupy shaded cracks and crevices, often in deep ravines, on quartz and in open quartz-grit pans. Plants are also found on vertical cliff faces.
This succulent 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 |
| Plants have been subject to illegal collection of mature individuals for the international trade in ornamental succulents. Although plants confiscated by the authorities in South Africa have only been identified to species level, this subspecies is the most common and widespread form of the species and most of the collections are likely to be this subspecies. This taxon has been highly sought after by collectors and is highly likely to remain so in future. As a result a population decline of 50-60% is suspected over three generations (90 years).
Anthropogenic climate change is a long-term threat to this taxon. 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 53% and 93% by 2080 for this succulent. However, as this taxon occurs across several vegetation units it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to 33%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This dwarf succulent is sometimes locally highly abundant but often each stand consists of just a few established plants. There are no formal estimates of population size for this taxon but there are likely between 200,000 and 500,000 mature individuals. The population is in decline due to illegal collection for the ornamental succulent plant trade. The population is also suspected to be declining due to an extended drought in the Richtersveld that started in 2016 and is still ongoing at the time of assessment.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum stephanii Schwantes subsp. helmutii (Lavis) S.A.Hammer | NT B1ab(v)+2ab(v) | 2020.1 | | Conophytum stephanii Schwantes subsp. helmutii (Lavis) 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.
Hammer, S.A. 1993. The genus Conophytum: A conograph. Succulent Plant Publications, Pretoria.
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.
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.
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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. 2021. Conophytum stephanii Schwantes subsp. helmutii (Lavis) S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2025/04/13 |
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