Taxonomy
Scientific Name
Conophytum piluliforme (N.E.Br.) N.E.Br. subsp. piluliforme
Higher Classification
Dicotyledons
Family
AIZOACEAE
Synonyms
Conophytum advenum N.E.Br., Conophytum aggregatum (Haw. ex N.E.Br.) N.E.Br., Conophytum archeri Lavis (in part), Conophytum archeri Lavis var. archeri, Conophytum brevipetalum Lavis, Conophytum etaylorii Schwantes, Conophytum leightoniae L.Bolus, Conophytum piluliforme (N.E.Br.) N.E.Br. var. advenum (N.E.Br.) Rawé, Conophytum piluliforme (N.E.Br.) N.E.Br. var. brevipetalum (Lavis) Rawé, Conophytum subconfusum Tischer, Mesembryanthemum aggregatum Haw. ex N.E.Br., Mesembryanthemum piluliforme N.E.Br.
National Status
Status and Criteria
Endangered A3c
Assessment Date
2021/12/01
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
Justification
This succulent is endemic to the Western Cape of South Africa, with an extent of occurrence (EOO) 2,841 km2, and an area of occupancy (AOO) of 36 km2. A future decline of 50% of the population due to illegal collection is suspected given the current demand for this genus for the ornamental plant trade. Anthropogenic climate change is a major threat to this taxon. Whilst climate models predict a near-complete 99-100% loss of suitable bioclimatic habitat by 2080 (generation length 20 years) under likely emission scenario RCP 2.6, this taxon occurs across several vegetation units and is expected to show a level of resilience to climate change. Thus while model predictions place this species in the category Critically Endangered under criterion A3, the uncertainty of the response given the expected resilience of this taxon means the degree of population decline is downgraded by 20% to 79% and this species therefore qualifies for Endangered under criterion A3.
Distribution
Endemism
South African endemic
Provincial distribution
Western Cape
Range
This succulent is endemic to the Western Cape of South Africa.
Habitat and Ecology
Major system
Terrestrial
Major habitats
Succulent Karoo
Description
This taxon is endemic to the Rainshadow Valley Karoo bioregion of the Succulent Karoo bioregion. The plants inhabit small areas covered with quartzite stones. This succulent has a generation length of 20 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 succulent 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. A future decline of less than 50% of the population is expected due to illegal collection as the plants are well dispersed across its range and can be quite cryptic. 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 two more widely distributed Conophytum species occurring within the same region is used as an indication of likely impact to this succulent. Whilst climate models predict a loss of suitable bioclimatic envelope of between 99% and 100% by 2080 for Conophytum taxa within the region under likely emission scenario RCP 2.6, this taxon occurs across several vegetation units and is expected to show a level of resilience to climate change. The population decline is therefore reduced by 20% to 79%. Species in this genus have limited dispersal ability and migration to suitable habitats elsewhere is regarded as highly unlikely.
Population

It is widespread and reported from many locations and subpopulations. It is locally common, sometimes locally abundant. There are no formal estimates of population size for this subspecies but there are likely between 30,000 and 100,000 mature individuals extant. The number of plants in this general area have been in decline in recent years due to an extended drought and the population may be in decline.


Population trend
Unknown
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Conophytum piluliforme (N.E.Br.) N.E.Br. subsp. piluliforme 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. 2021. Conophytum piluliforme (N.E.Br.) N.E.Br. subsp. piluliforme. National Assessment: Red List of South African Plants version . Accessed on 2024/12/06

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Distribution map

© J.H. Vlok/A.L. Schutte-Vlok


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