| Scientific Name | Conophytum devium G.D.Rowley subsp. stiriferum S.A.Hammer & Barnhill | Higher Classification | Dicotyledons | Family | AIZOACEAE |
National Status | Status and Criteria | Endangered A3d | Assessment Date | 2021/11/22 | 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 with an extent of occurrence (EOO) of 59 km² and area of occupancy (AOO) of 16 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 in future is therefore regarded as high for this particular taxon. Although it is recorded from a small number of locations and has a very small population size the plants are amongst the smallest in the genus and have a semi-subterranean habit which renders them highly cryptic. This may serve to limit future population decline to 75% within the next three generations (90 years). Climate change is also highly likely to impact the population although there is uncertainty of the response given the expected resilience of this taxon. It therefore qualifies as Endangered under criterion A3. |
Distribution | Endemism | South African endemic | Provincial distribution | Northern Cape | Range | This dwarf succulent is endemic to the Northern Cape province of South Africa. |
Habitat and Ecology | Major system | Terrestrial | Major habitats | Kosiesberg Succulent Shrubland, Eastern Gariep Rocky Desert | Description | Plants are restricted to the Gariep Desert bioregion of the Desert biome. This taxon favours relatively flat areas of feldspar-quartzite where only a small part of the plant may be exposed under favourable conditions rendering it highly cryptic except when in flower. This succulent 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 taxon is not currently threatened by illegal collection but it is very likely that it will likely become a target in coming years as the majority of other species in the genus have been increasingly targeted since 2019 including closely related taxa from the same region. Despite its remote location the small population size renders this taxon very susceptible to such activity.
There is no decline in habitat quality for this succulent as inferred by changes in vegetation cover determined from changes in Enhanced Vegetation Index (EVI) between 1984 and 2018 using Landsat data (Venter et al. 2020). While it is not possible to model the response of this taxon to climate change due to its restricted distribution, the average loss to climate change for 14 more widely distributed Conophytum species occurring within the same region is used as an indication of likely impact 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 32% and 81% by 2080 for Conophytum taxa within the region. However, as this taxon possesses certain 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 12%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population | This succulent is one of the smallest in the genus and is also highly cryptic, having a semi-subterranean habit. There are no formal estimates of population size but is likely to be fewer than 1,500 mature individuals. It is not known if the population is currently declining.
| Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum devium G.D.Rowley subsp. stiriferum S.A.Hammer & Barnhill | Rare | 2015.1 | | Conophytum devium G.D.Rowley subsp. stiriferum S.A.Hammer & Barnhill | 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.
Venter, A.M. 2000. Taxonomy of the genus Lycium (Solanaceae) in Africa. Unpublished Ph.D., University of the Orange Free State, Bloemfontein.
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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 devium G.D.Rowley subsp. stiriferum S.A.Hammer & Barnhill. National Assessment: Red List of South African Plants version . Accessed on 2025/04/19 |
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