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Scientific Name | Conophytum tantillum N.E.Br. subsp. amicorum S.A.Hammer & Barnhill |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A4cd; B1ab(iii,v)+2ab(iii,v) |
Assessment Date | 2021/12/09 |
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) and area of occupancy (AOO) of 4 km2. The population is in decline due to illegal collection for the international trade in ornamental succulents with at least one third of the population removed illegally 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 extremely high for this particular taxon. The single small location close to habitation coupled with the small population size of fewer than 2,000 mature individuals makes the taxon very susceptible to very rapid declines. A complete decline of up to 100% of the population is very likely within a single generation (30 years). 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. Climate change will also contribute to population decline. It therefore qualifies for listing as Critically Endangered under criteria A4 and B1+2. |
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 only found in a single location with a severely restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Blomveld |
Description | This is endemic to Namaqualand Blomveld in the Namaqualand Hardeveld bioregion of the Succulent Karoo biome. The plants typically occupy cracks and crevices on large quartz blocks and occasionally seen on 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 |
| This succulent has been highly sought after by collectors with at least a thousand plants removed illegally from the only known location in 2021 alone, representing at least one third of the total population. It is highly likely to continue to be targeted in coming years. The single range-restricted location makes the taxon highly susceptible to further rapid decline in the population through a single event and a complete decline in the population is likely within a single generation (30 years).
There is a decline in habitat quality for this taxon as inferred by changes in vegetation cover determined from changes in Enhanced Vegetation Index (EVI) between 1984 and 2018 using Landsat data (Venter et al. 2020). Anthropogenic climate change is a long-term threat to this succulent. 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 75% and 99% by 2080 for this taxon. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This is a very range restricted taxon known only from a single subpopulation of fewer than 2,000 mature individuals (South African National Biodiversity Institute field survey 2021). The population is in decline due to illegal collection for the ornamental succulent plant trade. At least 1,000 plants have been removed from habitat between 2019 and the end of 2021 based on confiscation records, with many more having likely been removed but not intercepted by law enforcers.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum tantillum N.E.Br. subsp. amicorum S.A.Hammer & Barnhill | CR B1ab(v)+2ab(v) | 2020.1 | | Conophytum tantillum N.E.Br. subsp. amicorum S.A.Hammer & Barnhill | VU D1+2 | 2017.1 | | Conophytum tantillum N.E.Br. subsp. amicorum S.A.Hammer & Barnhill | Least Concern | Raimondo et al. (2009) | |
Bibliography |
Hammer, S. and Barnhill, C. 1997. Odes part two: descriptions of new Mesembryanthema. Bradleya 15:42-47.
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.
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. & Mhlongo, N.N. 2021. Conophytum tantillum N.E.Br. subsp. amicorum S.A.Hammer & Barnhill. National Assessment: Red List of South African Plants version . Accessed on 2025/04/22 |
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