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Scientific Name | Conophytum maughanii N.E.Br. subsp. maughanii |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum rufescens N.E.Br., Ophthalmophyllum maughamii (N.E.Br.) Schwantes, Ophthalmophyllum rufescens (N.E.Br.) Tischer, Ophthalmophyllum schuldtii Schwantes |
National Status |
Status and Criteria | Vulnerable A4cd |
Assessment Date | 2021/11/30 |
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 12,239 km2 and area of occupancy (AOO) of 172 km2. The population is in decline due to the collection for the illegal ornamental succulent plant trade, with collection pressures likely to increase. The threat of illegal collection is therefore regarded as very high for this particular taxon, although it's scattered distribution in remote areas together with its cryptic semi-subterranean habit is likely to limit collection. A decline of between 30 and 45% of the population is likely within the next three generations (90 years). Modelling of climate change impacts is predicted to result in an average loss of 54% of suitable bio-climatic habitat by 2080 under likely CO2 emission scenarios (RCP 2.6). However, this taxon occurs across several vegetation units and possesses certain traits that together are expected to provide a level of resilience to climate change. Thus while model predictions place this taxon in the category Endangered under criterion A4, the expected population decline has been reduced by 20% to 34% based on the uncertainty of the response to climate change.
This succulent therefore qualifies as Vulnerable under criterion A4. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | Northern Cape |
Range | This succulent is endemic to the Northern Cape province of South Africa and the Karas region of southern Namibia. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Desert, Nama Karoo, Succulent Karoo |
Description | This succulent is primarily found in the Succulent Karoo but is also present in the Desert and Nama-Karoo Biomes. The plants inhabit flat or gently sloping patches (sometimes extensive) of quartz gravel where they have a semi-subterranean habit. This taxon 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 taxon is currently threatened by illegal collection for the international trade in ornamental succulents and the population is in decline as a result. This is likely to increase in future as there has been a dramatic increase in the number of species and volume of plants targeted since 2019. The cryptic semi-subterranean habit of this succulent may have buffered it to a degree from the impacts of collecting. As a result a population decline of 30-45% is suspected over three generations (90 years).
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 succulent 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 54% and 80% by 2080 for this taxon. However, as this taxon possesses certain morphological traits likely to afford resilience to xerophytic conditions and is found 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 34%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
It is a widespread taxon that often occurs as scattered individuals or small colonies. It is sometimes locally abundant. This succulent has a semi-subterranean habit with an inconspicuous flower so can be very cryptic in habitat. The population size can therefore be difficult to determine and is probably underestimated. There are probably in excess of 100,000 individuals. The population is in decline due to illegal collection for the ornamental succulent plant trade. At least 1,000 plants have been removed from habitat between 2019 and the end of 2021 based on confiscation records, with many more having likely been removed but not intercepted by law enforcers.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum maughanii N.E.Br. subsp. maughanii | 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).
Opel, M.R. 2004. The rediscovery of Crassula alcicornis. Haseltonia 10:38-40.
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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 maughanii N.E.Br. subsp. maughanii. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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