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Scientific Name | Conophytum jucundum (N.E.Br.) N.E.Br. subsp. fragile (Tischer) S.A.Hammer |
Higher Classification | Dicotyledons |
Family | AIZOACEAE |
Synonyms | Conophytum avenantii L.Bolus, Conophytum fragile Tischer, Conophytum middlemostii L.Bolus, Conophytum nordenstamii L.Bolus, Conophytum wettsteinii (A.Berger) N.E.Br. subsp. fragile (Tischer) S.A.Hammer |
National Status |
Status and Criteria | Endangered A4d |
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 Northern Cape province of South Africa with an extent of occurrence (EOO) of 3,108 km² and area of occupancy (AOO) of 128 km². The population is in decline due to illegal collection for the ornamental succulent plant trade, with collection likely to increase as there has been a dramatic increase in the number of species and volume of plants targeted since 2019. The population is also declining in response to climate change with drought related mortality having been observed, although there is uncertainty of the extent of the response given the expected resilience of this taxon. A decline of 50% of the population is suspected within the next three generations (90 years). It therefore qualifies as Endangered under criterion A4. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Northern Cape |
Range | This succulent is endemic to the Richtersveld region in the Northern Cape province of South Africa where it is recorded from numerous subpopulations. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Stinkfonteinberge Eastern Apron Shrubland, Lekkersing Succulent Shrubland, Goariep Mountain Succulent Shrubland, Umdaus Mountains Succulent Shrubland, Kosiesberg Succulent Shrubland, Rooiberg Quartz Vygieveld, Western Gariep Lowland Desert, Kahams Mountain Desert, Noms Mountain Desert |
Description | This succulent is found in both the Succulent Karoo and Desert biomes, where it is endemic to the Richtersveld (where it is most abundant) and Gariep Desert bioregions. It is widespread across eight vegetation units. The plants may be found on gneiss, pegmatite and quartz rubble. 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 for the international trade in ornamental succulents, with more than 1,000 mature individuals (identified to species level only) confiscated from poachers since 2019. Most of the individual subspecies of this succulent are challenging to distinguish and it is almost certain that this particular taxon has been collected in high numbers. Collection 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. Anthropogenic climate change is a long-term threat to this succulent. Loss of vegetation cover has been observed across the geographic range occupied by this taxon via Landsat imagery between 1984 and 2018 indicating a decline in habitat quality. Monitoring of one subpopulation showed a 30% decline from 2014-2018 as a result of drought (SANParks survey 2020). 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 65% and 99% by 2080 for this taxon. However, as this taxon occurs 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 45%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely. |
Population |
This is known from numerous subpopulations where it is often locally common or abundant. There are no formal estimates of population size but is likely to be well in excess of 50,000 mature individuals. However, in response to an extended drought in the Richtersveld that started in 2016 and is still ongoing at the time of assessment and illegal collection, the population is declining. One subpopulation monitored by South African National Parks board experienced a 30% decline as a result of drought related mortality between 2014 and 2018.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Conophytum jucundum (N.E.Br.) N.E.Br. subsp. fragile (Tischer) S.A.Hammer | NT A4a; B1ab(v)+2ab(v) | 2020.1 | | Conophytum jucundum (N.E.Br.) N.E.Br. subsp. fragile (Tischer) S.A.Hammer | 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 jucundum (N.E.Br.) N.E.Br. subsp. fragile (Tischer) S.A.Hammer. National Assessment: Red List of South African Plants version . Accessed on 2024/12/03 |
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