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Scientific Name | Conophytum arthurolfago S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum lithopsoides L.Bolus subsp. arturolfago S.A.Hammer |
National Status |
Status and Criteria | Critically Endangered B1ab(v) |
Assessment Date | 2021/11/08 |
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 where it only recorded from a single location with an extent of occurrence (EOO) of 32 km² and area of occupancy (AOO) of 24 km². In 2021 plants were illegally collected for the trade in ornamental succulents. The continued threat of illegal collection remains very high with the narrow geographic range rendering the species highly susceptible to further rapid decline due to this activity. A reduction of up to 75% of the population is deemed likely within the next three generations (90 years) based on a combination of illegal collection and the impacts of climate change. Given its single location and ongoing decline from illegal collection this species qualifies as Critically Endangered under criterion B1. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to a small area of the Northern Cape province of South Africa where it is only found in a single location with a restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Klipkoppe Shrubland |
Description | This species is only found in the Succulent Karoo biome, within the Namaqualand Hardeveld and Knersvlakte bioregions. It is subject to a winter rainfall regime. The plants are scattered across areas of quartz rubble and small outcrops, where they often occupy niche spots in small cracks and crevices. Plants are also found on flat, often terraced, areas of small quartz rocks. 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 succulent has been subject to the illegal collection of mature individuals for the international trade in ornamental succulents in 2020-21. This species has been sought after by collectors and is highly likely to remain so in future. The limited geographic range occupied by the species renders it very sensitive to such activity. A decline in the population of 50-75% is likely for this species. Livestock grazing is another potential threat to this species.
Anthropogenic climate change is a long-term threat to this species, however no loss of vegetation cover as inferred from changes in Enhanced Vegetation Index (EVI) between 1984 and 2018 using Landsat data (Venter et al. 2020) has been experienced at the only known location for this species. 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 71% and 99% by 2080 for Conophytum taxa within the region. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
The population size is not known although informal observations suggest individual subpopulations may be small (c.100 plants). Several subpopulations are known to exist and there are probably in excess of 2,500 mature individuals. The population is declining due to 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 arthurolfago S.A.Hammer | Rare | 2017.1 | | Conophytum arthurolfago S.A.Hammer | 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).
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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 arthurolfago S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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