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Scientific Name | Wolffiella denticulata (Hegelm.) Hegelm. |
Higher Classification | Monocotyledons |
Family | LEMNACEAE |
National Status |
Status and Criteria | Vulnerable D2 |
Assessment Date | 2007/09/17 |
Assessor(s) | C.R. Scott-Shaw & L. von Staden |
Justification | Known from four locations. Potentially threatened by habitat degradation due to water extraction, pollution and urban development. |
Distribution |
Endemism | Not endemic to South Africa |
Provincial distribution | KwaZulu-Natal |
Range | Northern KwaZulu-Natal between Mtunzini and Kosi Bay and in Mozambique. |
Habitat and Ecology |
Major system | Freshwater |
Major habitats | Swamp Forest |
Description | Floating in coastal freshwater marshes, lakes or slow moving streams. |
Threats |
| There are many impacts on the habitat of this species outside the Greater St. Lucia Wetland Park, which mostly results in decreasing water quality.
Around Mtunzini and Richards Bay river systems near the coast are undoubtedly degraded and impacted by pollution and eutrophication. However, some species of the Lemnaceae are quite tolerant of eutrophication and are used as indicators of eutrophied systems, but not enough is known about the ecology of Wolffiella denticulata to say whether it is tolerant of pollution or not. Fairly recent collections from the Richards Bay area could indicate that this species is able to persist despite degradation of water quality.
Water extraction for agricultural and household purposes from the Mkuze and Mbazwane River systems around Mbazwane (Sodwana Bay), where most collections of this species come from, could possibly impact on the habitat by reducing water levels (C.R. Scott-Shaw pers. comm.).
Industrial and urban development around Richards Bay could result in a loss of habitat if the Nseleni River system were to be channelled (as has happened to most of the streams in the harbour area) but legislation against wetland destruction could prevent this. However, in spite of legislation developments do not always proceed sensitively and this remains a serious potential threat. |
Population |
Population trend | Stable |
Conservation |
| The habitat of this species in South Africa is mostly well protected within the Greater St. Lucia Wetland Park. |
Assessment History |
Taxon assessed |
Status and Criteria |
Citation/Red List version | | Wolffiella denticulata (Hegelm.) Hegelm. | VU D2 | Raimondo et al. (2009) | | Wolffiella denticulata (Hegelm.) Hegelm. | VU | Scott-Shaw (1999) | |
Bibliography |
Cook, C.D.K. 2004. Aquatic and wetland plants of southern Africa. Backhuys Publishers, Leiden, The Netherlands.
Obermeyer-Mauve, A.A. 1966. A note on two rarely seen minute flowering plants, Wolffiella denticulata and W. welwitschii (Lemnaceae). South African Journal of Science 62:277-278.
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.
Scott-Shaw, C.R. 1999. Rare and threatened plants of KwaZulu-Natal and neighbouring regions. KwaZulu-Natal Nature Conservation Service, Pietermaritzburg.
Sieben, E.J.J. 2009. The status and distribution of vascular plants (Magnoliophyta, Lycophyta, Pteridophyta). In: W.R.T. Darwall, K.G. Smith, D. Tweddle and P. Skelton (eds.), The status and distribution of freshwater biodiversity in southern Africa (pp. 83-98), IUCN and SAIAB, Gland, Switzerland and Grahamstown, South Africa.
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Citation |
| Scott-Shaw, C.R. & von Staden, L. 2007. Wolffiella denticulata (Hegelm.) Hegelm. National Assessment: Red List of South African Plants version . Accessed on 2025/02/18 |
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