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Scientific Name | Conophytum obscurum N.E.Br. subsp. obscurum |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum clavatum L.Bolus, Conophytum indutum L.Bolus, Conophytum pulchellum Tischer |
National Status |
Status and Criteria | Vulnerable A4cd |
Assessment Date | 2021/12/01 |
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 with an extent of occurrence (EOO) of 5,200 km2 and area of occupancy (AOO) of 144 km2. The population is experiencing initial decline due to illegal collection for the 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 high for this particular taxon. The large number of known subpopulations and relatively large population size is likely to limit declines due to collection and an overall decline of 35% of the population is suspected within the next three generations (90 years). Climate change is also impacting the population, with loss of vegetation cover already causing ongoing decline in habitat quality. It therefore qualifies as Vulnerable 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 is predominantly found in the Richtersveld. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Succulent Karoo |
Description | This dwarf succulent is primarily restricted to quartzite outcrops (in full sun or partial shade) in the Richtersveld bioregion of the Succulent Karoo biome.
This taxon 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 succulent has been subject to illegal collection for the international trade in ornamental succulents and the population is in decline. 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. As a result a population decline of 30-35% is suspected over three generations (90 years). Anthropogenic climate change is a long-term threat to this succulent. Loss of vegetation cover has been observed across the geographic range occupied by this succulent via Landsat imagery between 1984 and 2018 indicating a decline in habitat quality. 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 24% and 26% by 2080 for this taxon. 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 4%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
It is known from a large number of locations across its range where it is often locally abundant. There are no formal estimates of population size but there are likely between 250,000 and 500,000 mature individuals. The population is experiencing initial levels of decline due to illegal collection for the ornamental succulent plant trade. This taxon can be locally abundant, however in response to an extended drought in the Richtersveld that started in 2016 and is still ongoing at the time of assessment, the population is suspected to be declining.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum obscurum N.E.Br. subsp. obscurum | 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.
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 obscurum N.E.Br. subsp. obscurum. National Assessment: Red List of South African Plants version . Accessed on 2024/12/07 |
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