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Scientific Name | Geissorhiza tenella Goldblatt |
Higher Classification | Monocotyledons |
Family | IRIDACEAE |
Synonyms | Engysiphon roseus (Schinz) G.J.Lewis |
National Status |
Status and Criteria | Near Threatened B2b(ii,iii,v); C2a(i) |
Assessment Date | 2023/06/20 |
Assessor(s) | D. Raimondo, N.A. Helme & L. von Staden |
Justification | This species has an extent of occurrence (EOO) of 45 938 km² and an area of occupancy (AOO) of 308 km². There are 47 locations known and subpopulations are fragmented. The overall population is suspected to have fewer than 12 000 individuals and subpopulations typically have fewer than 250 mature individuals. It continues to decline due to ongoing habitat loss to urban and coastal development and alien plant invasion. It is therefore listed as Near Threatened, almost meeting criteria B and C to be listed as Vulnerable. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | It is endemic to the Western Cape province of South Africa, extending from Yzerfontein in the north to Still Bay in the southeast and to the Cape Peninsula. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Peninsula Sandstone Fynbos, Canca Limestone Fynbos, Agulhas Limestone Fynbos, Albertinia Sand Fynbos, Agulhas Sand Fynbos, Hangklip Sand Fynbos, Cape Flats Sand Fynbos, Atlantis Sand Fynbos, Hartenbos Dune Thicket |
Description | It occurs on sandy, seasonally wet flats and dunes, flowering well after fire. |
Threats |
| This species has lost 36% of its habitat (calculated using landcover data in GIS) to crop cultivation, urban expansion (particularly on the Cape Flats) and coastal development, habitat loss is ongoing. Alien plant invasion of its sandy coastal habitats is a threat across this species' range. |
Population |
The population has a decreasing trend. It is known from 47 fragmented extant subpopulations, there are data available for 17 subpopulations all of which have fewer than 250 mature individuals. The overall population is therefore suspected to be less than 12 000 individuals. Many subpopulations have been lost in the past.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Geissorhiza tenella Goldblatt | VU B1ab(ii,iii,iv,v) | Raimondo et al. (2009) | |
Bibliography |
Goldblatt, P. 1985. Systematics of the southern African genus Geissorhiza (Iridaceae-Ixioideae). Annals of the Missouri Botanical Garden 72(2):277-447.
Goldblatt, P. and Manning, J.C. 2000. Cape Plants: A conspectus of the Cape Flora of South Africa. Strelitzia 9. National Botanical Institute, Cape Town.
Goldblatt, P. and Manning, J.C. 2020. Iridaceae of southern Africa. Strelitzia 42. South African National Biodiversity Institute, Pretoria.
Goldblatt, P., Manning, J.C. and Nänni, I. 2009. New species of Geissorhiza (Iridaceae:Crocoideae) from the southern African winter rainfall zone, range extensions, taxonomic changes, and notes on pollen morphology. Bothalia 39(2):123-152.
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.
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Citation |
| Raimondo, D., Helme, N.A. & von Staden, L. 2023. Geissorhiza tenella Goldblatt. National Assessment: Red List of South African Plants version . Accessed on 2024/09/08 |
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