|
Scientific Name | Conophytum turrigerum (N.E.Br.) N.E.Br. |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Mesembryanthemum turrigerum N.E.Br. |
National Status |
Status and Criteria | Critically Endangered A3cd |
Assessment Date | 2021/12/10 |
Assessor(s) | A.J. Young, J.E. Victor, S.A. Hammer & D. Raimondo |
Justification | This succulent is endemic to the Western Cape of South Africa where it is only recorded from a small number of localities with an extent of occurrence (EOO) of 283 km2 and area of occupancy (AOO) of 36 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 have been illegally removed from habitat with a dramatic increase in the number of species and volume of plants targeted since 2019. The small population size found across a limited number of locations (7-12) means that the threat of illegal collection is regarded as very high for this particular species. A decline of up to 90% of the population is likely within the next three generations (90 years). Climate change is also likely to contribute to population reduction although there is uncertainty of the response given the expected resilience of this species. It therefore qualifies as Critically Endangered under criterion A3. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | This species is endemic to a small part of the Western Cape of South Africa. It is recorded from between seven and 12 locations. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Swartland Granite Renosterveld, Boland Granite Fynbos |
Description | This dwarf succulent is endemic to the Granite & Dolerite Renosterveld and Granite Fynbos bioregions of the Fynbos biome. The plants inhabit damp areas in cracks and depressions on moss- and lichen-covered granite rocks.
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. The small population size found across a limited number of locations means a decline of up to 90% of the population is likely within the next three generations (90 years) due to illegal collection.
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). 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 five 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 occurs in a sheltered habitat 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 12%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely.
The type locality appears to be lost due to quarrying. The site was visited twice between 2010 and 2020 but both visits failed to locate any plants. |
Population |
The numerous subpopulations of this succulent are often small (sometimes fewer than 200 mature individuals) and relatively isolated. There are no formal estimates of population size for this species but there are likely between 2,500 and 7,500 mature individuals.
|
Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum turrigerum (N.E.Br.) N.E.Br. | VU B1ab(v)+2ab(v) | 2020.1 | | Conophytum turrigerum (N.E.Br.) N.E.Br. | Rare | Raimondo et al. (2009) | | Conophytum turrigerum (N.E.Br.) N.E.Br. | Not Threatened | Hilton-Taylor (1996) | |
Bibliography |
Goldblatt, P. and Manning, J.C. 2000. Cape Plants: A conspectus of the Cape Flora of South Africa. Strelitzia 9. National Botanical Institute, Cape Town.
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).
Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.
Manning, J.C. and Goldblatt, P. 2012. Plants of the Greater Cape Floristic Region 1: The Core Cape Flora. Strelitzia 29. South African National Biodiversity Institute, Pretoria.
Opel, M.R. 2004. The rediscovery of Crassula alcicornis. Haseltonia 10:38-40.
Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
|
Citation |
| Young, A.J., Victor, J.E., Hammer, S.A. & Raimondo, D. 2021. Conophytum turrigerum (N.E.Br.) N.E.Br. National Assessment: Red List of South African Plants version . Accessed on 2025/04/13 |
Comment on this assessment
