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Scientific Name | Conophytum pubescens (Tischer) G.D.Rowley |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Ophthalmophyllum pubescens Tischer |
National Status |
Status and Criteria | Endangered A4d |
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 729 km2 and area of occupancy (AOO) of 68 km2. The population is in decline due to illegal collection for the ornamental succulent plant trade. Collection is 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 species. However the plants can be cryptic in nature due to their semi-subterranean habit and are dispersed across its geographic range as isolated plants or small colonies of a few plants. This is suspected to limit the decline to 50% of the population 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 Endangered under criterion A4. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to the Bushmanland region of the Northern Cape province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Fynbos, Succulent Karoo |
Description | This succulent is predominately found in the Succulent Karoo biome, primarily in the Namaqualand Hardeveld bioregion. It occurs in several vegetation units including Namaqualand Klipkoppe Shrubland, Namaqualand Blomveld, Platbakkies Succulent Shrubland and Namaqualand Granite Renosterveld. It is typically found on quartz patches and, more rarely, on calcrete.
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 |
| Plants have been subject to illegal collection of mature individuals for the international trade in ornamental succulents with several hundred plants being removed since 2019. This species has been highly sought after by collectors and is highly likely to remain so in future. As a result a population decline of 50% is suspected over three generations (90 years).
Anthropogenic climate change is a long-term threat to this species. 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). 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 54% and 89% by 2080 for this species. 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 34%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
It is typically found in small colonies across its geographic range. There are no formal estimates of population size for this species but the number is likely between 25,000 and 100,000 mature individuals. The population is experiencing initial levels of decline due to illegal collection for the ornamental succulent plant trade.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum pubescens (Tischer) G.D.Rowley | 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 pubescens (Tischer) G.D.Rowley. National Assessment: Red List of South African Plants version . Accessed on 2025/04/13 |
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