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Scientific Name | Conophytum hanae Pavelka |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum tomasii Halda (invalidly published) |
National Status |
Status and Criteria | Critically Endangered A3d |
Assessment Date | 2021/11/29 |
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 location 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 (estimated at no more than 2,500 mature individuals). Climate change is also highly likely to impact the population although there is uncertainty of the response given the expected resilience of this taxon. A complete decline of up to 100% 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 dwarf succulent is only known from a single location in the Northern Cape province of South Africa. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Klipkoppe Shrubland |
Description | This succulent is endemic to the Namaqualand Hardeveld bioregion of the Succulent Karoo biome. Plants are typically found growing on gneiss in shaded cracks and crevices. 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. Its small population size, single location and limited geographic distribution makes the species highly susceptible to collection and a complete loss of mature individuals is likely.
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 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 species occupies a very sheltered habitat 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. However, this species occupies a very sheltered niche that may provide some resilience to climate change and this is not used to inform the overall assessment. |
Population |
The area where this species is found remains poorly explored and this succulent has only rarely been seen in habitat. The population size is thought to be approx. 1,000-2,500 mature individuals but this may be an underestimation. 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 hanae Pavelka | VU D2 | 2020.1 | | Conophytum hanae Pavelka | Rare | 2017.1 | | Conophytum tomasi Halda | Data Deficient (Taxonomically Problematic) | 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 hanae Pavelka. National Assessment: Red List of South African Plants version . Accessed on 2024/12/03 |
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