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Scientific Name | Steirodiscus tagetes (L.) Schltr. |
Higher Classification | Dicotyledons |
Family | ASTERACEAE |
Synonyms | Gamolepis tagetes (L.) DC., Othonna tagetes L., Psilothonna tagetes (L.) E.Phillips |
National Status |
Status and Criteria | Vulnerable B1ab(ii,iii,iv,v) |
Assessment Date | 2016/01/29 |
Assessor(s) | D. Raimondo, N.A. Helme & L. von Staden |
Justification | EOO 5325 km², six to eight remaining locations continue to decline due to ongoing habitat loss and degradation, as well as competition from alien invasive plants. |
Distribution |
Endemism | South African endemic |
Provincial distribution | Western Cape |
Range | Cape West Coast between St Helena Bay and False Bay. |
Habitat and Ecology |
Major system | Terrestrial |
Major habitats | Cape Flats Dune Strandveld, Langebaan Dune Strandveld, Saldanha Limestone Strandveld, Saldanha Flats Strandveld, Saldanha Granite Strandveld, Hangklip Sand Fynbos, Cape Flats Sand Fynbos, Atlantis Sand Fynbos, Hopefield Sand Fynbos |
Description | Sand dunes near the coast with strandveld vegetation. |
Threats |
| Habitat loss to urban expansion is the most severe threat to this species, and has already caused the loss of more than half of known locations. Loss continues on the False Bay coast, around Melkbosstrand, Atlantis and on the Vredenburg Peninsula, where rapidly expanding coastal development is threatening many local endemic plant species. Relatively large pieces of intact habitat remains on the West Coast between Melkbosstrand and Langebaan, but much of it is invaded with unmanaged alien invasive plants, which are outcompeting native species. Alien invasive plants, especially Australian Rooikrans Wattle, is also causing much ongoing habitat degradation along the False Bay coast. |
Population |
The population of this formerly widespread and common species has been much reduced by habitat loss to urban expansion on the Cape Flats, where it is now locally extinct, except for one small subpopulation occurring in a nature reserve near Milnerton. It possibly still persists on the False Bay coast near Macassar, but its habitat is severely degraded and rapidly disappearing due to urban expansion as well as spreading informal settlements. It was last recorded in this area in 1995. Large subpopulations still occur on the West Coast near Atlantis and Koeberg, and a smaller subpopulation was recently recorded at St Helena Bay. This species is highly likely to occur in the West Coast National Park near Langebaan, where it is known from historical records.
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Population trend | Decreasing |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Steirodiscus tagetes (L.) Schltr. | VU B1ab(ii,iii,iv,v) | Raimondo et al. (2009) | |
Bibliography |
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.
Manning, J.C., Goldblatt, P. and Joubert, L. 2013. A taxonomic revision of the small Cape genus Steirodiscus (Asteraceae: Senecioneae). Bothalia 43(1):109-119.
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. 2016. Steirodiscus tagetes (L.) Schltr. National Assessment: Red List of South African Plants version . Accessed on 2025/01/25 |
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