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Scientific Name | Conophytum blandum L.Bolus |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Endangered A4acd |
Assessment Date | 2021/11/15 |
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 and has an extent of occurrence (EOO) of 201 km² and area of occupancy (AOO) of 56 km², it is known from between eight and 10 locations. The population is experiencing some decline due to the illegal ornamental succulent plant trade, with collection likely to increase as there has been a dramatic increase in the number of species and volume of Conophytum plants targeted since 2019. The continued threat of illegal collection is therefore regarded as very high for this particular species. Climate change is also impacting the population and an overall decline by 50-75% within the next three generations (90 years) is suspected. It therefore qualifies as Endangered under criterion A4. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This species is endemic to the Northern Cape province of South Africa where it inhabits some isolated hills in a relatively small corner of western Bushmanland. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Bushmanland Inselberg Shrubland, Namaqualand Blomveld, Bushmanland Arid Grassland |
Description | This dwarf succulent is found on isolated quartz-rich inselbergs in the Succulent Karoo and Nama-Karoo biomes (Richtersveld, Namaqualand Hardeveld and Bushmanland & West Griqualand bioregions). It is primarily found on Bushmanland Inselberg Shrubland. This area receives sporadic winter rainfall. 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 is widespread across several inselbergs in northwestern Bushmanland, often on farmed land or communal land. Grazing and trampling by livestock is a threat to some subpopulations. Some of the subpopulations occur on mineral rich substrates presenting a risk from expansion of mining activities in the general area. Plants have been subject to 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. A population decline of up to 75% is suspected from this activity within three generations.
Anthropogenic climate change is a long-term threat 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 19% (RCP 2.6) and 95% (RCP 8.5) by 2080 for this species. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. However, as this taxon occurs across several vegetation units it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to negligible levels based on the uncertainty of the response given the expected resilience of this taxon.
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 across the geographic range for this species. |
Population |
It is very common across several quartz inselbergs, where it is often locally abundant. No formal population count exists but there are many thousand mature individuals, often forming large clusters as old plants. The population is declining due to illegal collection for the succulent ornamental plant trade.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum blandum L.Bolus | VU B1ab(iii,v) | 2020.1 | | Conophytum blandum L.Bolus | NT D2 | Raimondo et al. (2009) | | Conophytum blandum L.Bolus | Lower Risk - Near Threatened | Victor (2002) | | Conophytum blandum L.Bolus | 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., Rodgerson, C., Van Wyk, P.C.V. & Mhlongo, N.N. 2021. Conophytum blandum L.Bolus. National Assessment: Red List of South African Plants version . Accessed on 2024/12/07 |
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