|
Scientific Name | Conophytum roodiae N.E.Br. subsp. roodiae |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum hallii L.Bolus, Conophytum primosii Lavis, Conophytum rubroniveum L.Bolus |
National Status |
Status and Criteria | Critically Endangered A4d |
Assessment Date | 2023/10/26 |
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 and the Western Cape provinces of South Africa where it has an extent of occurrence (EOO) of 3,475 km2 and an area of occupancy (AOO) of 112 km2. The population is in decline due to illegal collection for the international trade in ornamental succulents and several thousand plants have been removed from habitat since 2019. Illegal collection is likely to increase as there has been a dramatic increase in the number of species and volume of plants targeted since 2019, with this taxon being highly sought after. It also has a short generation length and is challenging to grow in cultivation. The continued threat of illegal collection is therefore regarded as extremely high for this particular succulent. A decline of up to 80% of the population is very likely within the next three generations (45 years). It therefore qualifies as Critically Endangered under criterion A4. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape, Western Cape |
Range | This taxon is endemic to the Northern Cape and Western Cape provinces of South Africa. It is predominantly found in Namaqualand but at least one subpopulation extends south into the Western Cape. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Heuweltjieveld, Namaqualand Blomveld, Namaqualand Klipkoppe Shrubland |
Description | This succulent is endemic to the Namaqualand Hardeveld bioregion of the Succulent Karoo biome. The plants are primarily found on granite domes where they occupy the gaps between exfoliating layers of rock or occupy shallow grit-filled depressions, sometimes almost filling the pans.
This taxon has a generation length of 15 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 |
| Plants have been subject to illegal collection of mature individuals for the international trade in ornamental succulents with several thousand plants removed from habitat since 2019. This particular taxon has been highly sought after by collectors and is highly likely to remain so in future.
There is no decline in habitat quality for this taxon 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). Anthropogenic climate change is a long-term threat to this succulent. 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 78% and 99% by 2080 for this taxon. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. However, as this taxon possesses traits that may provide some resilience, and given the uncertainty of this taxon's response to climate change and the fact that it has a generation length of only 15 years, climate predictions are not used to inform the overall assessment. |
Population |
There are no formal estimates of population size for this taxon but the number of mature individuals is likely to be between 10,000 and 50,000 individuals. The population is in decline due to illegal collection for the ornamental succulent plant trade. At least 4,300 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.
|
Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum roodiae N.E.Br. subsp. roodiae | NT B1ab(v)+2ab(v) | 2020.1 | | Conophytum roodiae N.E.Br. subsp. roodiae | 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.
|
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. 2023. Conophytum roodiae N.E.Br. subsp. roodiae. National Assessment: Red List of South African Plants version . Accessed on 2024/12/07 |
Comment on this assessment
