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Scientific Name | Conophytum velutinum Schwantes subsp. velutinum |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum craterulum Tischer, Conophytum tischeri Schick, Conophytum velutinum Schwantes var. craterulum (Tischer) Rawé |
National Status |
Status and Criteria | Critically Endangered 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 is endemic to the Northern Cape province of South Africa with an extent of occurrence (EOO) and area of occupancy (AOO) of 16 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. The relatively small population size at two locations, both in the immediate vicinity of habitation makes the taxon highly susceptible to collection. Climate change is also highly likely to impact the population although there is uncertainty of the response given the expected resilience of this taxon. An overall decline of up to 90% of the population is likely within the next three generations (90 years). It therefore qualifies as Critically Endangered under criterion A3. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This succulent is endemic to the Northern Cape province of South Africa where it is only found in two locations with a restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Klipkoppe Shrubland |
Description | This taxon is endemic to the Namaqualand Hardeveld bioregion of the Succulent Karoo biome. The plants occupy shaded places on quartz. This succulent 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 taxon 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. A population decline of 75-90% is suspected over three generations (90 years) as a result of this activity.
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 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 52%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
There are no formal estimates of population size for this succulent but the number of mature individuals is likely to be no more than 5,000. 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 velutinum Schwantes subsp. velutinum | Rare | Raimondo et al. (2009) | | Conophytum velutinum Schwantes subsp. velutinum | Lower Risk - Near Threatened | Victor (2002) | | Conophytum velutinum Schwantes subsp. velutinum | Rare | Hilton-Taylor (1996) | |
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).
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.
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 velutinum Schwantes subsp. velutinum. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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