Eriospermum subincanum | SANBI Sensitive Species

Assessor: Sarah Schumann

Sensitive in 2010

Family

Ruscaceae

Reason for the sensitivity status

Several species of the Eriospermum genus have been targeted by illegal harvesters. This species is in demand and of interest in the international horticultural trade. Plants of this genus were among those targeted and confiscated during criminal prosecutions of illegal plant collecting. Few known locations of occurrence with existing threat 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 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 Endangered as it is known from four locations that are threatened with ongoing habitat loss to agriculture (Helme & Raimondo, 2007). This genus is in demand and of 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 (Confiscation Lists (2016-2021) provided by Cape Nature, SANBI Kirstenbosch Botanical Garden, SANBI Karoo Desert Botanic Garden, SANParks Sendelingsdrift Botanic Garden and Department of Forestry, Fisheries and the Environment). This suggests that this genus is being targeted and that endangered species may be at risk.

Helme, N.A. & Raimondo, D. 2007. Eriospermum subincanum P.L.Perry. 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 is known from four locations and has experienced minimum of 10% loss of habitat to rooibos tea cultivation whereby a further 30% loss is predicted in the next 20 years (species generation length is estimated at 25 years) (Helme & Raimondo, 2007).

Helme, N.A. & Raimondo, D. 2007. Eriospermum subincanum P.L.Perry. 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 of occurrence with existing threat (Helme & Raimondo, 2007), places the persistence of this species at risk. Were exploitation to also occur, recruitment and recovery may be poor. Generally Eriospermums are long-lived, slow-growing tuberous genus that have a high regeneration rate for most species. Can form large local populations quite quickly but majority of species are rare in the landscape making them vulnerable to illegal collection. Species are usually locally abundant but multiplication can be slow and small. (van Jaarsveld. E, Helme. N & Peckover. R, personal communication 2021, 14 October)

Helme, N.A. & Raimondo, D. 2007. Eriospermum subincanum P.L.Perry. National Assessment: Red List of South African Plants version 2020.1.

Reference file

Eriospermum Auction.pdf508.21 KB

Eriospermum interest.pdf440.07 KB

Heme & Raimondo 2007 Eriospermum subincanum Threatened Species Programme _ SANBI Red List of South African Plants.pdf625.36 KB