Gladiolus quadrangulus | SANBI Sensitive Species

Assessor: Sarah Schumann

Sensitive in 2010

Family

Iridaceae

Reason for the sensitivity status

This genus is in demand and of popular interest in international horticultural trade. Plants of this genus were among those targeted and confiscated during criminal prosecutions of illegal plant collecting. Few known subpopulations with 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 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 seven highly fragmented subpopulations that is threatened with habitat loss from development, alien invasive plant encroachment, water extraction and livestock overgrazing (Raimondo et al. 2005). This genus is currently in demand and of popular interest in international horticultural trade, as indicated by several online marketplace, e-commerce and auction sites. Another species of this genus is known to be threatened with harvesting of wild individuals (Victor & Duncan, 2010). Plants of this genus were among those targeted and/or confiscated during recent criminal prosecutions of illegal plant collecting. This suggests that this genus may be targeted and that endangered species may be at risk to over-exploitation.

Raimondo, D., Goldblatt, P. & Preston, H. 2005. Gladiolus quadrangulus (D.Delaroche) Barnard. National Assessment: Red List of South African Plants version 2020.1.

Victor, J.E. & Duncan, G.D. 2010. Gladiolus aureus Baker. 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 2514 km² and is known from seven highly fragmented subpopulations with several ongoing threats (Raimondo et al. 2005), making this species vulnerable.

Raimondo, D., Goldblatt, P. & Preston, H. 2005. Gladiolus quadrangulus (D.Delaroche) Barnard. 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, fragmented subpopulations with several threats (Raimondo et al. 2005), makes this species vulnerable to further population loss. Were exploitation also to occur, recruitment and recovery may be poor.

Raimondo, D., Goldblatt, P. & Preston, H. 2005. Gladiolus quadrangulus (D.Delaroche) Barnard. National Assessment: Red List of South African Plants version 2020.1.

Reference file

Gladiolus quadrangulus Threatened Species Programme _ SANBI Red List of South African Plants.pdf742.26 KB

gladiolus.pdf786.27 KB