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Scientific Name | Conophytum loeschianum Tischer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum intermedium L.Bolus, Conophytum rubricarinatum Tischer, Conophytum saxetanum (N.E.Br.) N.E.Br. var. loeschianum (Tischer) Rawé |
National Status |
Status and Criteria | Endangered A3d+4c |
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 Karas region of Namibia and the Northern Cape province of South Africa with an extent of occurrence (EOO) of 1,238 km² and area of occupancy (AOO) of 80 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 high for this particular species, although its scattered distribution across many subpopulations in remote, and sometimes inaccessible areas, is likely to limit collection. A decline of between 50-70% of the population is likely within the next three generations.
Modelling of climate change impacts is predicted to result in an average loss of 97% of suitable bio-climatic habitat by 2080 under likely CO2 emission scenarios (RCP 2.6). This species occurs across several vegetation units which may provide a level of resilience to climate change. Thus while model predictions place this species in the category Critically Endangered under criterion A4 the uncertainty of the response given the expected resilience of this species means the category is downgraded to Endangered. This species therefore qualifies as Endangered under criteria A3 and A4. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | Northern Cape |
Range | This is one of the handful of species in the genus that is found in both Namibia (Karas region) and South Africa (the Richtersveld region of the Northern Cape province). The plant occupies a narrow stretch of land on either side of the Orange River. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Desert, Succulent Karoo |
Description | This dwarf succulent is restricted to the Desert and Succulent Karoo biomes; Gariep Desert, Southern Namib Desert and Richtersveld bioregions. The plants occupy quartz flats and ridges, often small in extent. 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. A decline in the population of 50-70% is possible in three generations (90 years) due to this activity.
Anthropogenic climate change is a long-term threat to this taxon. Loss of vegetation cover has been observed across the geographic range occupied by this species via Landsat imagery between 1984 and 2018 indicating a decline in habitat quality. 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 97% and 100% by 2080 for this species. 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 77%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
The population size is estimated to consist of between 20,000 and 50,000 mature individuals and occurs as many dispersed subpopulations. This species can be locally abundant, however in response to an extended drought in the Richtersveld that started in 2016 and is still ongoing at the time of assessment, the population is suspected to be declining.
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Population trend | Unknown |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum loeschianum Tischer | Least Concern | Raimondo et al. (2009) | | Conophytum loeschianum Tischer | Lower Risk - Least Concern | Victor (2002) | | Conophytum loeschianum Tischer | 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 loeschianum Tischer. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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