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Scientific Name | Conophytum verrucosum (Lavis) G.D.Rowley |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Ophthalmophyllum verrucosum Lavis |
National Status |
Status and Criteria | Vulnerable A3cd |
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 succulent species is endemic to the Northern Cape province of South Africa with an extent of occurrence (EOO) of 5,772 km2 and area of occupancy (AOO) of 68 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 high for this particular species. The highly scattered distribution of the plants across a featureless and remote landscape coupled with the semi-subterranean cryptic nature of this species is likely to limit any decline to between 30 and 40% of the population within the next three generations (90 years). Climate change is suspected to contribute towards a decline of 8% of the population by 2080. It therefore qualifies as Vulnerable under criterion A3 |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to Bushmanland in the Northern Cape province of South Africa where it is known from numerous locations across a broad geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Bushmanland Basin Shrubland, Bushmanland Arid Grassland |
Description | This dwarf succulent is found in the Succulent Karoo and Nama-Karoo biomes; Namaqualand Hardeveld, Trans-Escarpment Succulent Karoo and Bushmanland & West Griqualand bioregions. The plants are found on both quartz and 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 |
| This particular succulent 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 have experienced substantial declines in population number due to illegal collection. Its relatively wide distribution and cryptic nature may limit declines as a result of this activity to less than 40% of the population over three generations (90 years) although some subpopulations may be severely depleted.
There is no decline in habitat quality for this species 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 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 8% and 81% by 2080 for this species. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This is a widespread succulent species usually occurring as scattered individuals, but also sometimes being locally common. The semi-subterranean habit and general remoteness of the area makes an estimation of population size very difficult but is likely to comprise between 50,000 and 250,000 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 verrucosum (Lavis) G.D.Rowley | LC | 2017.1 | | Conophytum verrucosum (Lavis) G.D.Rowley | Rare | Raimondo et al. (2009) | | Conophytum verrucosum (Lavis) G.D.Rowley | Lower Risk - Least Concern | Victor (2002) | | Conophytum verrucosum (Lavis) G.D.Rowley | Indeterminate | Hilton-Taylor (1996) | | Ophthalmophyllum verrucosum Lavis | Indeterminate | Hall et al. (1980) | |
Bibliography |
Hall, A.V., De Winter, M., De Winter, B. and Van Oosterhout, S.A.M. 1980. Threatened plants of southern Africa. South African National Scienctific Programmes Report 45. CSIR, Pretoria.
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).
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
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.
Rowley, G.D. 1978. Reunion of some genera of Mesembryanthemaceae. National Cactus and Succulent Journal 33(1):6-9.
Snijman, D.A. 2013. Plants of the Greater Cape Floristic Region 2: The extra Cape flora. Strelitzia 30. South African National Biodiversity Institute, Pretoria.
Victor, J.E. 2002. South Africa. In: J.S. Golding (ed), Southern African plant Red Data Lists. Southern African Botanical Diversity Network Report 14 (pp. 93-120), SABONET, 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 verrucosum (Lavis) G.D.Rowley. National Assessment: Red List of South African Plants version . Accessed on 2025/07/26 |
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