Assessor: Sarah Schumann
According to the IUCN Red List Assessment, this subspecies is Critically Endangered as it is experiencing high levels of population decline due to the threat of illegal collection of mature individuals for the international trade in ornamental succulents in 2020-21 (Young, 2022). As of 2019, this genus has become popular in trade and there is a high demand from international and domestic horticultural markets for wild collected plants as indicated by media, police reports and several online marketplace, e-commerce, and auction sites (Trenchard 2021; Hyman 2020; Majikela 2020; Myburgh 2021; Friedman 2021; Tshuma 2021). This species was among those targeted and confiscated during a recent criminal prosecution of illegal plant collecting (Ramatseba 2021). There has been several recorded confiscations of the species and others of the genus from illegal plant collection (Confiscation Lists (2019-2021) provided by Cape Nature, SANBI Karoo Desert National Botanical Garden, SANBI Kirstenbosch Botanical Garden, SANParks Sendelingsdrift Botanic Garden and the Department of Forestry, Fisheries and the Environment). This suggests that this genus and subspecies is being targeted and is threatened with illegal collecting.
Friedman, B. 2021. 24 May 2021. South Africa targeted for rare plant poaching placing biodiversity at risk. Cape Talk. Available at: https://www.capetalk.co.za/articles/417213/south-africa-targeted-for-rare-plant-poaching-placing-biodiversity-at-risk
Hyman, A. 2020. 1 February 2020. Koreans fined R5m as poachers target SA's succulent treasure chest. Times Live. Available at: https://www.timeslive.co.za/news/south-africa/2020-02-01-koreans-fined-r5m-as-poachers-target-sas-succulent-treasure-chest/
Majikela, M. 2020. 31 January 2020. Hefty sentencing for possession of Conophytum plants. Media Statement. South African Police Service Office of the Provincial Commissioner Western Cape. Available at: https://www.saps.gov.za/newsroommsspeechdetail.php?nid=24491
Myburgh, A. 2021. 20 January 2021. Man behind bars for possession of endangered plants (Conophytum). Media Statement South African Police Service, Office of the Provincial Commissioner North West. Available at: https://www.saps.gov.za/newsroom/msspeechdetail.php?nid=24491
Ramatseba, BM. 2021. 12 January 2021. Ten appear for dealing in protected plants. Media Statement. South African Police Service, Office of the Provincial Commissioner Northern Cape. Available at: https://www.saps.gov.za/newsroom/msspeechdetail.php?nid=3036
Trenchard, T. 2021. 31 July 2021. In South Africa, Poachers Now Traffic in Tiny Succulent Plants. The New York Times. Available at: https://www.nytimes.com/2021/07/31/world/africa/south-africa-poachers-tiny-succulent-plants.html
Tshuma, N. 2021. 20 May 2021. Collectors drive a spike in theft of indigenous plants in the Western Cape. IOL. Available at: https://www.iol.co.za/capeargus/news/collectors-drive-a-spike-in-theft-of-indigenous-plants-in-the-western-cape-e120f529-741b-43a7-8454-cb8f69544878
Young, A. 2022. (assessment in prep 2022) Conophytum calculus subsp. calculus. The IUCN Red List of Threatened Species.
This species was once widespread and common however the population is decreasing and is estimated to decrease by 30-40% in the next three generations (Young & Raimondo 2020). This taxon has an extent of occurrence of 2629km² (Young & Raimondo 2020). A formal population size estimate is not available but it is likely in excess of 20,000 mature individuals (Young, 2022). A total of 11 600 plants have been confiscated from plant poachers with many others likely not to have been intercepted (Young, 2022).
Hammer, S. 2002. Dumpling and his wife: New view of the genus Conophytum. EAE Creative Colour, Norwich.
Young, A.J. & Raimondo, D. 2020. Conophytum calculus (A.Berger) N.E.Br. subsp. calculus. National Assessment: Red List of South African Plants version 2020.1.
Young, A. 2022. (assessment in prep 2022) Conophytum calculus subsp. calculus The IUCN Red List of Threatened Species.
Whole individuals are recorded in confiscations.
This taxon is slow growing (Young & Raimondo 2020). Regeneration potential for the vast majority of the Conophytum genus is very poor as recruitment is low and dependent on successive, appropriate weather conditions. Seeds are not known to disperse. Regeneration will take decades. (Young, personal communication 2021, 5 October)
Young, A.J. & Raimondo, D. 2020. Conophytum calculus (A.Berger) N.E.Br. subsp. calculus. National Assessment: Red List of South African Plants version 2020.1.