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Scientific Name | Conophytum pellucidum Schwantes subsp. saueri S.A.Hammer & T.Smale |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A3d |
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) and area of occupancy (AOO) of 8 km2. The dwarf succulents that comprise this genus have been increasingly targeted by illegal collection in recent years and the vast majority of species are in high demand by collectors. Whilst there is no evidence of illegal collection at the time of this submission, closely related species, including some from the immediate area, have been illegally removed from habitat with a dramatic increase in the number of species and volume of plants targeted since 2019. The threat of illegal collection is therefore regarded as very high for this particular succulent. Given its single location and very small population size of fewer than 750 mature individuals a complete decline of up to 100% of the population is likely within the next 10 years (one generation). Climate change is also predicted to impact the population by 2080, however, given the current raising trend in illegal collection of succulents, it is more likely that this succulent will be poached to extinction within the next 10 years. It therefore qualifies as Critically Endangered under criterion A3. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This dwarf 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 | Platbakkies Succulent Shrubland |
Description | This succulent is restricted to the Namaqualand Hardeveld bioregion of the Succulent Karoo biome where it is found in shallow fine sand filled grit pans on granite. This taxon has a generation length of 10 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 is not currently threatened by illegal collection but it is likely that it will become a target in coming years as there has been a dramatic increase in the number of species and volume of plants of this genus targeted since 2019. Related species within the immediate area have experienced severe declines in population number due to illegal collection. Despite its relatively remote location the single location and small population size makes the taxon highly susceptible to collection. As a result a population decline of 90-100% is suspected over three generations (30 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), however, anthropogenic climate change remains 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 77% and 98% by 2080 for this succulent. However, as this taxon possesses certain traits likely to afford resilience to xerophytic conditions it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to 57%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This is only known from a single range-restricted population of approx. 500-750 mature individuals. The number of plants in this general area have been in decline in recent years due to an extended drought and the population may be in decline.
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Population trend | Unknown |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum pellucidum Schwantes subsp. saueri S.A.Hammer & T.Smale | VU D1+2 | 2017.1 | | Conophytum pellucidum Schwantes subsp. saueri S.A.Hammer & T.Smale | 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 pellucidum Schwantes subsp. saueri S.A.Hammer & T.Smale. National Assessment: Red List of South African Plants version . Accessed on 2024/12/07 |
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