Taxonomy
Scientific Name
Gnidia sonderiana Meisn.
Higher Classification
Dicotyledons
Family
THYMELAEACEAE
National Status
Status and Criteria
Endangered B1ab(iii,v)+2ab(iii,v)
Assessment Date
2018/05/24
Assessor(s)
N.A. Helme & L. von Staden
Justification
Gnidia sonderiana is a highly localized species with an extent of occurrence (EOO) of 10 km². It is known from three locations, and is threatened by spreading, severe infestations of alien invasive plants at one location, and invasive plants are present in low abundance at a second location. It is potentially threatened by too frequent fire across its range.
Distribution
Endemism
South African endemic
Provincial distribution
Western Cape
Range
This species is endemic to the Babilonstoring Mountains in the Western Cape.
Habitat and Ecology
Major system
Terrestrial
Major habitats
Overberg Sandstone Fynbos
Description
It occurs on rocky slopes in sandstone fynbos.
Threats
Unmanaged alien invasive plants are present at two locations, and recent field observations indicate that density is increasing. These are likely to outcompete native species in the near future if not urgently cleared. This species occurs in a very small area on a single mountain range, and alien invasive plants are likely to the rest of the population in the near future. This species is also potentially threatened by too frequent fire, as it appears to be rarer in areas that are frequently burnt (N.A. Helme pers. obs. 2006).
Population

This rare and localized species has been recorded over a very small area. Plants occur in low numbers in fire refugia among rocks, and appear to be sensitive to too frequent fire (N.A. Helme pers. obs.). The population requires monitoring, and is likely to decline due to competition from spreading alien invasive plants.


Population trend
Decreasing
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Gnidia sonderiana Meisn.VU D22015.1
Gnidia sonderiana Meisn.EN DRaimondo 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.


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
Helme, N.A. & von Staden, L. 2018. Gnidia sonderiana Meisn. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2020/10/28

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Distribution map

© N.A. Helme


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