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Scientific Name | Conophytum armianum S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Endangered A4d; B1ab(iii,v)+2ab(iii,v) |
Assessment Date | 2021/11/08 |
Assessor(s) | A.J. Young, P.G. Desmet, I. Ebrahim, D. Guo, A. Harrower, L. Jabar, L. Knoetze, P.C.V. Van Wyk & N.N. Mhlongo |
Justification | This cryptic species is endemic to the Northern Cape province of South Africa where it occurs at one location with an extent of occurrence (EOO) of 227 km² and an area of occupancy (AOO) of 36 km². This dwarf succulent has been increasingly targeted by illegal collection in recent years and is in high demand by collectors. During 2020-21 plants were illegally collected from habitat for the trade in ornamental succulents. 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. Anthropogenic climate change climate change is also impacting the population but there is some uncertainty of the response given the expected resilience of this taxon. An overall decline to the population of up to 75% of the population is possible within three generations (60 years). This species therefore qualifies as Endangered under criteria A4 and B1+2. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to a small part 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 | Umdaus Mountains Succulent Shrubland, Kosiesberg Succulent Shrubland, Central Richtersveld Mountain Shrubland |
Description | This species is found in the Succulent Karoo and Desert biomes where it is endemic to Richtersveld and Gariep Desert bioregions. This area only receives winter rainfall. It is found as single plants or clusters of no more than a few leaves (heads) in deposits of quartzite or feldspar rubble, usually on flatter or gently sloping areas buried amongst small stones. It is typically found on hill tops but some populations have been observed at ground level. Plants are extremely small (<0.5cm diameter) and can be very cryptic especially when in the summer rest period when the plants are sheathed with the previous season's dried leaf. 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 succulent has been subject to illegal collection for the specialist succulent trade in 2020-21. While the plant is cryptic all known subpopulations occupy a relatively limited geographic range making the species sensitive to such activity. A population decline of 50-75% is suspected over three generations due to this activity.
Anthropogenic climate change is a long-term threat to 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 21 more widely distributed Conophytum species occurring within the same region is used as an indication of likely impact to this species. There is no evidence that 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 in the area occupied by this species. Future 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 taxon possesses certain morphological 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 36% based on the uncertainty of the response given the expected resilience of this taxon. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This species is probably more abundant and widespread than current knowledge. The very small mature plants (to 5mm diameter) are highly cryptic and therefore easily overlooked which may result in an underestimation of both the number of subpopulations and individuals. At least 10 subpopulations each of several hundred plants have been discovered in recent years, all within the same small geographic area. The population is declining due to illegal harvesting 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 armianum S.A.Hammer | VU B1ab(v)+2ab(v) | 2020.1 | | Conophytum armianum S.A.Hammer | Rare | 2015.1 | | Conophytum armianum S.A.Hammer | NT D2 | Raimondo et al. (2009) | | Conophytum armianum S.A.Hammer | Lower Risk - Near Threatened | Victor (2002) | | Conophytum armianum 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).
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Citation |
| Young, A.J., Desmet, P.G., Ebrahim, I., Guo, D., Harrower, A., Jabar, L., Knoetze, L., Van Wyk, P.C.V. & Mhlongo, N.N. 2021. Conophytum armianum S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2024/10/06 |
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