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Scientific Name | Conophytum achabense S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Critically Endangered A4acd; B1ab(iii,v)+2ab(iii,v) |
Assessment Date | 2021/11/08 |
Assessor(s) | A.J. Young, I. Ebrahim, A. Harrower, L. Jabar, L. Knoetze, C. Rodgerson, P.C.V. Van Wyk, P.G. Desmet & N.N. Mhlongo |
Justification | This cryptic species 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. Here several thousand individuals occupy a very small part of a quartz-rich hill. This dwarf succulent has been increasingly targeted by illegal collection in recent years and is in high demand by collectors. In 2021 a substantial proportion of the global population was illegally collected for the illegal trade in succulents in a single event. The continued threat of illegal collection remains very high with the single location rendering the species highly susceptible to further rapid decline due to this activity and a decline of over 90% of the population is likely within three generations. The single location and inability to disperse also makes the species very susceptible to the deleterious effects of climate change. Loss of vegetation cover has been observed at this site via Landsat imagery between 1984 and 2018 and is used to infer that the habitat quality is already in decline. It therefore qualifies as Critically Endangered under criteria A4 and B1+2. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This dwarf succulent species is a South African endemic occupying a highly range-restricted area in the Northern Cape province. It is known only from a small part of a single quartz-rich inselberg in Bushmanland. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Bushmanland Inselberg Shrubland, Southern Richtersveld Inselberg Shrubland |
Description | This species is known only from a small part of an inselberg in the Bushmanland area of the Northern Cape Province of South Africa. The plants are endemic to the Nama-Karoo biome and the Richtersveld bioregion. This is a particularly dry region that can experience extended periods of drought coupled with extremely high temperatures. Here a dense population of plants occupies a narrow band on top of a broad quartz-rich plateau. This is amongst the smallest species of the genus and in habitat can be extremely cryptic, especially when out of flower. The base of the plant is typically concealed underground with only the dark green convex top visible through the supper layer of small quartz stones. This species has a generation length of 20 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 species has been increasingly targeted by illegal collection in recent years and is in high demand by collectors. The single location renders the species highly susceptible to rapid decline due to illegal collection. At least 3,400 plants were confiscated from poachers in 2020-21 by authorities in South Africa. There are reports that more than 15,000 mature plants were illegally removed from habitat and exported to China in 2021 alone.
Anthropogenic climate change is a long-term threat to this species. Due to its single location, it is not possible to model climate impacts to this species however, climate models for related species from the same region indicate an average loss of 56% of suitable bio-climatic habitat by 2080 under likely CO2 emission scenarios (RCP 2.6) (Hausfather and Peters 2020). This species has a combination of morphological and habitat traits that are expected to provide it with a level of resilience to climate change. There is therefore a high level of uncertainty of the response of this species to climate change however it is likely that climate change will contribute to population decline over the next three generations.
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 locality for this species.
The population occurs near an existing mine, and is potentially threatened by future activity in the immediate area. |
Population |
A locally abundant species, known from a single population consisting of several thousand plants localised to a small extent of a single inselberg. Estimating population size is challenging due to the highly cryptic nature of the species, especially when out of flower but up to 50,000 mature individuals may be present. The population is declining rapidly as a result of illegal collection with over 5,900 plants included in confiscations between March 2019 and January 2022, many more are likely to have been removed from the wild but not intercepted by law enforcement efforts.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum achabense S.A.Hammer | VU D2 | Raimondo et al. (2009) | | Conophytum achabense S.A.Hammer | VU D2 | Victor (2002) | | Conophytum achabense S.A.Hammer | 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).
Opel, M.R. 2004. The rediscovery of Crassula alcicornis. Haseltonia 10:38-40.
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Citation |
| Young, A.J., Ebrahim, I., Harrower, A., Jabar, L., Knoetze, L., Rodgerson, C., Van Wyk, P.C.V., Desmet, P.G. & Mhlongo, N.N. 2021. Conophytum achabense S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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