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Scientific Name | Conophytum pubicalyx Lavis |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Endangered A3cd |
Assessment Date | 2021/12/02 |
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 species is endemic to the Northern Cape province of South Africa with an extent of occurrence (EOO) of 518 km2 and area of occupancy (AOO) of 36 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 species given its limited number of subpopulations, furthermore climate change will also contribute to population decline although the expected population decline has been reduced by 20% to 52% based on the uncertainty of the response to climate change. An overall decline of between 50 and 75% of the population is likely within the next three generations (90 years). It therefore qualifies as Endangered under criterion A3. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to the Northern Cape province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Blomveld, Namaqualand Klipkoppe Shrubland |
Description | This succulent is primarily found in the Succulent Karoo biome (mainly in Namaqualand Hardeveld bioregion) but some populations extend into the Fynbos biome. The plants are typically found on flat patches of fine quartz stones but also occur on quartz-rich gneiss.
This species 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 particular species 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 of several subpopulations have experienced severe declines in population number due to illegal collection. As a result a population decline of at least 50% is suspected over three generations (90 years).
There is no 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). While it is not possible to model the response of this taxon to climate change due to its restricted distribution, the average loss to climate change for 15 more widely distributed Conophytum species occurring within the same region is used as an indication of likely impact to this species. 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 72% and 99% by 2080 for Conophytum taxa within the region. 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 52%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This succulent species is known from eight subpopulations where it can be locally abundant. There are no formal estimates of population size for this species but there are likely between 50,000 and 100,000 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 pubicalyx Lavis | VU B1ab(v)+2ab(v) | 2020.1 | | Conophytum pubicalyx Lavis | Rare | 2017.1 | | Conophytum pubicalyx Lavis | 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 pubicalyx Lavis. National Assessment: Red List of South African Plants version . Accessed on 2025/04/13 |
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