Crassula tuberella

Assessor: Sarah Schumann

Sensitive in 2010
No
Family
Crassulaceae
Reason for the sensitivity status
This genus is in demand and of popular interest in international horticultural trade. There have been several recorded confiscations of species of the Crassula genus from illegal collection. Few known locations and existing threats causing population decline makes this species vulnerable to further population loss. Were exploitation to also occur, recruitment and recovery may be poor. Releasing data on this species could exacerbate threat and vulnerability.

This species is either similar to another sensitive species or belongs to a group containing sensitive species, and is extremely rare in the wild. The localities of wild populations need to be protected to avoid loss to exploitation, which, due to its rarity, could drive the species to extinction within a very short time.
Exploitation extent
Uncertain - No data exists yet showing that this species is exploited in the wild, however it has one or more relatives or look-alike species (found in South Africa or globally) that are known to be utilised. This species has a similar life form or other relevant traits to its exploited relative(s), making it highly likely that it would be exploited for the same purposes.
Justification and references

According to the SANBI Red List Assessment, this species is Vulnerable as it is known from few locations that are experiencing population decline due to habitat loss and degradation (von Staden & Mtshali, 2020). This genus is in demand and of popular interest in international horticultural trade, as indicated by several online marketplace, e-commerce and auction sites. Plants of this genus were among those targeted and confiscated during recent criminal prosecutions of illegal plant collecting (Gamieldien SAPS, 2021). There have been several recorded confiscations of species of the Crassula genus from illegal collection (Confiscation List (2018-2021) provided by Cape Nature, SANParks Sendelingsdrift Botanic Garden, SANBI Kirstenbosch Botanical Garden and Karoo Desert Botanic Garden). This suggests that this genus is being targeted and that this species may be at risk.

Gamieldien, C.M. 2021. 28 May 2021. Operation Crassula nets successes worth millions. Media Statement. South African Police Service, Office of the Provincial Commissioner Northern Cape. Available at: https://www.saps.gov.za/newsroom/selnewsdetails.php?nid=32837

von Staden, L. & Mtshali, H. 2020. Crassula tuberella Toelken. National Assessment: Red List of South African Plants version 2020.1. 

Population vulnerability
Population is vulnerable: size is <= 2500 mature individuals OR the number of known subpopulations is <= 5 OR range is <= 100km2 OR species at risk of localised extinctions
Justification and references

This taxon has an extent of occurrence of  6244 km² and is known from less than 10 locations with a declining population size (von Staden & Mtshali, 2020).

von Staden, L. & Mtshali, H. 2020. Crassula tuberella Toelken. National Assessment: Red List of South African Plants version 2020.1. 

Targeted demographics
Unknown.
Regeneration potential
This species has a slow population growth rate, or the growth rate varies depending on habitat, and there is a poor chance the wild populations will recover from exploitation OR a collector might feasibly harvest the entire extant population removing the chance of subsequent recruitment.
Justification and references

Few known locations and existing threats (von Staden & Mtshali, 2020), makes this species vulnerable to further population loss. Were exploitation to also occur, recruitment and recovery may be poor.

von Staden, L. & Mtshali, H. 2020. Crassula tuberella Toelken. National Assessment: Red List of South African Plants version 2020.1.