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Scientific Name | Conophytum smaleorum Rodgerson & A.J.Young |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A3d |
Assessment Date | 2021/12/07 |
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 where it is only recorded from a single locality with an extent of occurrence (EOO) and area of occupancy (AOO) of 4 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 single location and small population size of fewer than 500 mature individuals, a complete decline of 100% of the population is likely within the next three generations (90 years). While climate change is also likely to impact this species the rapid declines to the population as a result of illegal collection means it qualifies as Critically 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 where it is only found in a single location with a very restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Kosiesberg Succulent Shrubland |
Description | This dwarf succulent is endemic to the Richtersveld bioregion of the Succulent Karoo biome. It is found as scattered individuals on quartz rocks and amongst rubble, occasionally in the shade of small shrubs.
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 have experienced severe declines in population number due to illegal collection. Despite its remote location the single location and small population size makes the species highly susceptible to collection.
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 species to climate change due to its restricted distribution, the average loss to climate change for 21 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 56% and 86% by 2080 for Conophytum taxa within the region. However, as this species occupies a sheltered habitat it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to 36%. 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 species but the number of mature individuals is probably in the range 500-1,000. Due to an extended drought in the Richtersveld that started in 2016 and is still ongoing at the time of assessment, the population is suspected to be declining.
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Population trend | Unknown |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum smaleorum Rodgerson & A.J.Young | VU D2 | 2020.1 | | Conophytum smaleorum Rodgerson & A.J.Young | Critically Rare | 2017.1 | |
Bibliography |
Hammer, S.A. 1993. The genus Conophytum: A conograph. Succulent Plant Publications, Pretoria.
Opel, M.R. 2004. The rediscovery of Crassula alcicornis. Haseltonia 10:38-40.
Rodgerson, C. and Young, A.J. 2013. Conophytum smaleorum: A new Knopie from the southern Richtersveld. CactusWorld 31(3):197-201.
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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 smaleorum Rodgerson & A.J.Young. National Assessment: Red List of South African Plants version . Accessed on 2024/09/15 |
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