|
Scientific Name | Dierama grandiflorum G.J.Lewis |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
National Status |
Status and Criteria | Endangered B1ab(iii) |
Assessment Date | 2016/11/18 |
Assessor(s) | C. McMaster & L. von Staden |
Justification | Dierama grandiflorum is an Eastern Cape endemic with an extent of occurrence (EOO) of 3444 km². It is known from two confirmed locations and possibly still extant at three other locations where it is known from historical records. It is declining due to ongoing habitat degradation, and is therefore listed as Endangered under criteria B1ab(iii). |
Distribution |
Endemism | South African endemic |
Provincial distribution | Eastern Cape |
Range | This species is endemic to South Africa, and is found in Graaff-Reinet and Somerset East. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Eastern Upper Karoo, Upper Karoo Hardeveld, Karoo Escarpment Grassland, Amathole Montane Grassland |
Description | It grows on grass slopes among rock outcrops. |
Threats |
| Dierama grandiflorum is declining due to ongoing habitat degradation as a result of livestock overgrazing. It is possible that a number of subpopulations known from historical records are now locally extinct due to overgrazing, but surveys of these sites are required to confirm this. |
Population |
An extremely rare and localized endemic known from less than 10 collections. Recent observations of subpopulations on the Bosberg indicate that plants occur in small, sparsely scattered clumps of fewer than 100 plants (C. McMaster pers. obs.). More field surveys are needed to relocate subpopulations known from historical records, but local extinctions are difficult to confirm as plants occur in small, localized stands that are easily overlooked.
|
Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Dierama grandiflorum G.J.Lewis | EN B1ab(iii) | 2017.1 | | Dierama grandiflorum G.J.Lewis | Rare | 2011.1 | | Dierama grandiflorum G.J.Lewis | Rare | Raimondo et al. (2009) | |
Bibliography |
Bredenkamp, C. In prep. Conspectus of the flora of the Eastern cape. Strelitzia.
Hilliard, O.M. and Burtt, B.L. 1991. Dierama: The hairbells of Africa. Acorn Books, Johannesburg and London.
Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
|
Citation |
| McMaster, C. & von Staden, L. 2016. Dierama grandiflorum G.J.Lewis. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14 |
Comment on this assessment
