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Scientific Name | Conophytum uviforme (Haw.) N.E.Br. subsp. decoratum (N.E.Br.) S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum decoratum N.E.Br., Conophytum occultum L.Bolus, Conophytum varians L.Bolus |
National Status |
Status and Criteria | Vulnerable A4d |
Assessment Date | 2021/12/10 |
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 is endemic to the Western Cape and Northern Cape provinces of South Africa with an extent of occurrence (EOO) of 20,286 km2 and area of occupancy (AOO) of 184 km2. The large population is in 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. The continued threat of illegal collection is therefore regarded as very high for this particular taxon. The population is predicted to decline by between 20-40% within the next three generations (90 years). Climate change is also highly likely to impact the population although there is uncertainty of the response given the expected resilience of this taxon. It therefore qualifies as Vulnerable under criterion A4. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape, Western Cape |
Range | This dwarf succulent is endemic to the Western Cape and Northern Cape provinces of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Succulent Karoo |
Description | This dwarf succulent is endemic to the Succulent Karoo biome where it is found in the Namaqualand Hardeveld and Namaqualand Sandveld bioregions. The plants typically inhabit exposed areas of granite, often living between eroding plates, under rock lips but also at the edges of shallow grit-filled depressions.
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 |
| Plants have been subject to illegal collection of mature individuals for the international trade in ornamental succulents with several hundred plants being removed from habitat since 2019. This taxon has been highly sought after by collectors and is highly likely to remain so in future. However the broad geographic distribution, numerous localities and large population size is likely to limit any decline to 20-40% of the population within the next three generations (90 years).
There is no decline in habitat quality for this succulent 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 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 29% and 76% by 2080 for this taxon. However, as this taxon possesses certain morphological traits likely to afford resilience to xerophytic conditions and is found 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 9%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This dwarf succulent is known from numerous localities and subpopulations where it is often locally abundant. There are no formal estimates of population size for this species but there are likely between 500,000 and 750,000 mature individuals. The population is in decline due to illegal collection for the ornamental succulent plant trade. Several hundred 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 uviforme (Haw.) N.E.Br. subsp. decoratum (N.E.Br.) 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.
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 uviforme (Haw.) N.E.Br. subsp. decoratum (N.E.Br.) S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2024/12/07 |
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