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Scientific Name | Conophytum tantillum N.E.Br. subsp. tantillum |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
National Status |
Status and Criteria | Endangered A4cd; B1ab(iii,v)+2ab(iii,v) |
Assessment Date | 2021/12/09 |
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) and area of occupancy (AOO) of 8 km² where it is only recorded from two locations. The population is experiencing initial levels of decline due to illegal collection for the international trade in ornamental succulents 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 including many from the immediate area. The continued threat of illegal collection is therefore regarded as extremely high for this particular taxon however its cliff habitat will make collection difficult and an overall decline of less than 75% is likely within the next three generations (90 years). Loss of vegetation cover has been observed at this site via Landsat imagery between 1984 and 2018 and is used to infer that the habitat quality is already in decline. Anthropogenic climate change climate change is also impacting the population but there is some uncertainty of the response given the expected resilience of this taxon. An overall decline to the population of up to 75% of the population is possible within three generations. It therefore qualifies as Endangered under criteria A4 and B1+2. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This dwarf succulent is endemic to the Northern Cape province of South Africa where it is only found in two locations with a restricted geographic range. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Namaqualand Shale Shrubland |
Description | This dwarf succulent is endemic to the Namaqualand Hardeveld bioregion of the Succulent Karoo biome. The plants are primarily cliff-dwelling occupying a sheltered niche.
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 |
| Plants have been subject to illegal collection of mature individuals for the international trade in ornamental succulents since 2019. As many of the plants confiscated by the authorities in South Africa have only been identified to species level all the subspecies are treated the same here and are therefore believed to have been collected illegally. This taxon has been highly sought after by collectors and is highly likely to remain so in future. Related species within the immediate area have experienced severe declines in population number due to illegal collection. A population decline of 50-75% is suspected over three generations (90 years) as a result of this activity. 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 75% and 99% by 2080 for this taxon. However, as this taxon occupies a very sheltered habitat it is expected to have a level of resilience to climate change and the expected population loss is reduced by 20% to 53%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. Loss of vegetation cover has been observed at this site via Landsat imagery between 1984 and 2018 and is used to infer that the habitat quality is already in decline. |
Population |
This succulent is currently known from two subpopulations with an estimated overall population size of approximately 5,000 mature individuals. It is possible that more subpopulations occurs as the cliff-dwelling habitat of the plants renders discovery difficult. The population is experiencing initial levels of decline due to illegal collection for the ornamental succulent plant trade.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum tantillum N.E.Br. subsp. tantillum | Rare | Raimondo et al. (2009) | |
Bibliography |
Hammer, S. 1991. Tantalus et tantillum. Cactus and Succulent Journal (USA) 63(3):139-141.
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.
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.
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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 tantillum N.E.Br. subsp. tantillum. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06 |
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